I have got very accurate location using FusedLocationProviderClient
(Google Play services required)
Permissions Required
android.permission.ACCESS_FINE_LOCATION
android.permission.ACCESS_COARSE_LOCATION
Dependency
'com.google.android.gms:play-services-location:15.0.0'
Kotlin Code
val client = FusedLocationProviderClient(this)
val location = client.lastLocation
location.addOnCompleteListener {
// this is a lambda expression and we get an 'it' iterator to access the 'result'
// it.result.latitude gives the latitude
// it.result.longitude gives the longitude
val geocoder = Geocoder(applicationContext, Locale.getDefault())
val address = geocoder.getFromLocation(it.result.latitude, it.result.longitude, 1)
if (address != null && address.size > 0) {
// Get the current city
city = address[0].locality
}
}
location.addOnFailureListener {
// Some error in getting the location, let's log it
Log.d("xtraces", it.message)
}
Add a background-color to the element and you will nicely see the difference of inline vs. block, as explained by the other posters.
If you round 8.8333333333339 to 2 decimals, the correct answer is 8.83, not 8.84. The reason you got 8.83000000001 is because 8.83 is a number that cannot be correctly reprecented in binary, and it gives you the closest one. If you want to print it without all the zeros, do as VGE says:
print "%.2f" % 8.833333333339 #(Replace number with the variable?)
It doesn't make a lot of sense, the original GAC was already quite capable of storing different versions of assemblies. And there's little reason to assume a program will ever accidentally reference the wrong assembly, all the .NET 4 assemblies got the [AssemblyVersion] bumped up to 4.0.0.0. The new in-process side-by-side feature should not change this.
My guess: there were already too many .NET projects out there that broke the "never reference anything in the GAC directly" rule. I've seen it done on this site several times.
Only one way to avoid breaking those projects: move the GAC. Back-compat is sacred at Microsoft.
string.replace(/^\s+|\s+$/g, "");
Although this question is already answered (tl;dr: yes, an empty href
value is valid), none of the existing answers references the relevant specifications.
An empty string can’t be a URI. However, the href
attribute doesn’t only take URIs as value, but also URI references. An empty string may be a URI reference.
HTML 4.01 uses RFC 2396, where it says in section 4.2. Same-document References (bold emphasis mine):
A URI reference that does not contain a URI is a reference to the current document. In other words, an empty URI reference within a document is interpreted as a reference to the start of that document, and a reference containing only a fragment identifier is a reference to the identified fragment of that document.
RFC 2396 is obsoleted by RFC 3986 (which is currently IETF’s URI standard), which essentially says the same.
HTML5 uses (valid URL potentially surrounded by spaces ? valid URL) W3C’s URL spec, which has been discontinued. WHATWG’s URL Standard should be used instead (see the last section).
HTML 5.1 uses (valid URL potentially surrounded by spaces ? valid URL) WHATWG’s URL Standard (see the next section).
WHATWG’s HTML uses (valid URL potentially surrounded by spaces) the definition of valid URL string from WHATWG’s URL Standard, where it says that it can be a relative-URL-with-fragment string, which must at least be a relative-URL string, which can be a path-relative-scheme-less-URL string, which is a path-relative-URL string that doesn’t start with a scheme string followed by :
, and its definition says (bold emphasis mine):
A path-relative-URL string must be zero or more URL-path-segment strings, separated from each other by U+002F (/), and not start with U+002F (/).
Here you have an example
$("#profiles-thread").select2({
minimumInputLength: 2,
tags: [],
ajax: {
url: URL,
dataType: 'json',
type: "GET",
quietMillis: 50,
data: function (term) {
return {
term: term
};
},
results: function (data) {
return {
results: $.map(data, function (item) {
return {
text: item.completeName,
slug: item.slug,
id: item.id
}
})
};
}
}
});
It's quite easy
To expand on RiggsFolly’s answer—or for anyone who is facing the same issue but is using Apache 2.2 or below—this format should work well:
Order Deny,Allow
Deny from all
Allow from 127.0.0.1 ::1
Allow from localhost
Allow from 192.168
Allow from 10
Satisfy Any
For more details on the format changes for Apache 2.4, the official Upgrading to 2.2 from 2.4 page is pretty clear & concise. Key point being:
The old access control idioms should be replaced by the new authentication mechanisms, although for compatibility with old configurations, the new module
mod_access_compat
is provided.
Which means, system admins around the world don’t necessarily have to panic about changing Apache 2.2 configs to be 2.4 compliant just yet.
There is no native but what if you use what I put in this post:
How to parse excel rows back to types using EPPlus
If you want to point it at a table only it will need to be modified. Something like this should do it:
public static IEnumerable<T> ConvertTableToObjects<T>(this ExcelTable table) where T : new()
{
//DateTime Conversion
var convertDateTime = new Func<double, DateTime>(excelDate =>
{
if (excelDate < 1)
throw new ArgumentException("Excel dates cannot be smaller than 0.");
var dateOfReference = new DateTime(1900, 1, 1);
if (excelDate > 60d)
excelDate = excelDate - 2;
else
excelDate = excelDate - 1;
return dateOfReference.AddDays(excelDate);
});
//Get the properties of T
var tprops = (new T())
.GetType()
.GetProperties()
.ToList();
//Get the cells based on the table address
var start = table.Address.Start;
var end = table.Address.End;
var cells = new List<ExcelRangeBase>();
//Have to use for loops insteadof worksheet.Cells to protect against empties
for (var r = start.Row; r <= end.Row; r++)
for (var c = start.Column; c <= end.Column; c++)
cells.Add(table.WorkSheet.Cells[r, c]);
var groups = cells
.GroupBy(cell => cell.Start.Row)
.ToList();
//Assume the second row represents column data types (big assumption!)
var types = groups
.Skip(1)
.First()
.Select(rcell => rcell.Value.GetType())
.ToList();
//Assume first row has the column names
var colnames = groups
.First()
.Select((hcell, idx) => new { Name = hcell.Value.ToString(), index = idx })
.Where(o => tprops.Select(p => p.Name).Contains(o.Name))
.ToList();
//Everything after the header is data
var rowvalues = groups
.Skip(1) //Exclude header
.Select(cg => cg.Select(c => c.Value).ToList());
//Create the collection container
var collection = rowvalues
.Select(row =>
{
var tnew = new T();
colnames.ForEach(colname =>
{
//This is the real wrinkle to using reflection - Excel stores all numbers as double including int
var val = row[colname.index];
var type = types[colname.index];
var prop = tprops.First(p => p.Name == colname.Name);
//If it is numeric it is a double since that is how excel stores all numbers
if (type == typeof(double))
{
if (!string.IsNullOrWhiteSpace(val?.ToString()))
{
//Unbox it
var unboxedVal = (double)val;
//FAR FROM A COMPLETE LIST!!!
if (prop.PropertyType == typeof(Int32))
prop.SetValue(tnew, (int)unboxedVal);
else if (prop.PropertyType == typeof(double))
prop.SetValue(tnew, unboxedVal);
else if (prop.PropertyType == typeof(DateTime))
prop.SetValue(tnew, convertDateTime(unboxedVal));
else
throw new NotImplementedException(String.Format("Type '{0}' not implemented yet!", prop.PropertyType.Name));
}
}
else
{
//Its a string
prop.SetValue(tnew, val);
}
});
return tnew;
});
//Send it back
return collection;
}
Here is a test method:
[TestMethod]
public void Table_To_Object_Test()
{
//Create a test file
var fi = new FileInfo(@"c:\temp\Table_To_Object.xlsx");
using (var package = new ExcelPackage(fi))
{
var workbook = package.Workbook;
var worksheet = workbook.Worksheets.First();
var ThatList = worksheet.Tables.First().ConvertTableToObjects<ExcelData>();
foreach (var data in ThatList)
{
Console.WriteLine(data.Id + data.Name + data.Gender);
}
package.Save();
}
}
Gave this in the console:
1JohnMale
2MariaFemale
3DanielUnknown
Just be careful if you Id field is an number or string in excel since the class is expecting a string.
Importing Maven dependencies may not work if you import the same path several times. This may happen automatically after importing an existing maven project. I can't figure out why this happens, so I'm inclined to think it is a bug.
For example, if my project is
hibernate
src/main
src/test
the three paths may be imported as top nodes:
hibernate
src/main
src/test
If such is the case, the dependencies appear to be right, but they won't be used until you remove the superfluous paths (in this case, src/main
and src/test
). Once you do this, refresh and click Build > Rebuild Project. IDEA will pick up the dependencies.
A symptom of this problem is that IDEA warns you of a duplicated path when you manually check a library (second screenshot in the question).
There are several ways to re-read the dependencies in case you need it. If you go to the “Maven Projects” tab, there is a “Reimport All Maven Projects” icon at the top left of the tab. If you suspect IDEA became confused you can click on File > Invalidate Caches.
You need a sound file to be served from somewhere. Here's the code from Scriptaculous's Sound library:
//Default:
<embed style="height:0" id="sound_#{track}_#{id}" src="#{url}" loop="false" autostart="true" hidden="true"/>
//For Gecko:
if(Prototype.Browser.Gecko && navigator.userAgent.indexOf("Win") > 0){
if(navigator.plugins && $A(navigator.plugins).detect(function(p){ return p.name.indexOf('QuickTime') != -1 }))
Sound.template = new Template('<object id="sound_#{track}_#{id}" width="0" height="0" type="audio/mpeg" data="#{url}"/>');
else if(navigator.plugins && $A(navigator.plugins).detect(function(p){ return p.name.indexOf('Windows Media') != -1 }))
Sound.template = new Template('<object id="sound_#{track}_#{id}" type="application/x-mplayer2" data="#{url}"></object>');
else if(navigator.plugins && $A(navigator.plugins).detect(function(p){ return p.name.indexOf('RealPlayer') != -1 }))
Sound.template = new Template('<embed type="audio/x-pn-realaudio-plugin" style="height:0" id="sound_#{track}_#{id}" src="#{url}" loop="false" autostart="true" hidden="true"/>');
else
Sound.play = function(){};
}
This worked for me Visual C++ Redistributable Packages
Just updating aleemb's original, much-upvoted answer with a couple of additions to the css.
We've been using the following combo:
.unselectable {
-webkit-touch-callout: none;
-webkit-user-select: none;
-khtml-user-select: none;
-moz-user-select: none;
-ms-user-select: none;
-o-user-select: none;
user-select: none;
}
We got the suggestion for adding the webkit-touch entry from:
http://phonegap-tips.com/articles/essential-phonegap-css-webkit-touch-callout.html
2015 Apr: Just updating my own answer with a variation that may come in handy. If you need to make the DIV selectable/unselectable on the fly and are willing to use Modernizr, the following works neatly in javascript:
var userSelectProp = Modernizr.prefixed('userSelect');
var specialDiv = document.querySelector('#specialDiv');
specialDiv.style[userSelectProp] = 'none';
C++ includes useful generic functions like std::for_each
and std::transform
, which can be very handy. Unfortunately they can also be quite cumbersome to use, particularly if the functor you would like to apply is unique to the particular function.
#include <algorithm>
#include <vector>
namespace {
struct f {
void operator()(int) {
// do something
}
};
}
void func(std::vector<int>& v) {
f f;
std::for_each(v.begin(), v.end(), f);
}
If you only use f
once and in that specific place it seems overkill to be writing a whole class just to do something trivial and one off.
In C++03 you might be tempted to write something like the following, to keep the functor local:
void func2(std::vector<int>& v) {
struct {
void operator()(int) {
// do something
}
} f;
std::for_each(v.begin(), v.end(), f);
}
however this is not allowed, f
cannot be passed to a template function in C++03.
C++11 introduces lambdas allow you to write an inline, anonymous functor to replace the struct f
. For small simple examples this can be cleaner to read (it keeps everything in one place) and potentially simpler to maintain, for example in the simplest form:
void func3(std::vector<int>& v) {
std::for_each(v.begin(), v.end(), [](int) { /* do something here*/ });
}
Lambda functions are just syntactic sugar for anonymous functors.
In simple cases the return type of the lambda is deduced for you, e.g.:
void func4(std::vector<double>& v) {
std::transform(v.begin(), v.end(), v.begin(),
[](double d) { return d < 0.00001 ? 0 : d; }
);
}
however when you start to write more complex lambdas you will quickly encounter cases where the return type cannot be deduced by the compiler, e.g.:
void func4(std::vector<double>& v) {
std::transform(v.begin(), v.end(), v.begin(),
[](double d) {
if (d < 0.0001) {
return 0;
} else {
return d;
}
});
}
To resolve this you are allowed to explicitly specify a return type for a lambda function, using -> T
:
void func4(std::vector<double>& v) {
std::transform(v.begin(), v.end(), v.begin(),
[](double d) -> double {
if (d < 0.0001) {
return 0;
} else {
return d;
}
});
}
So far we've not used anything other than what was passed to the lambda within it, but we can also use other variables, within the lambda. If you want to access other variables you can use the capture clause (the []
of the expression), which has so far been unused in these examples, e.g.:
void func5(std::vector<double>& v, const double& epsilon) {
std::transform(v.begin(), v.end(), v.begin(),
[epsilon](double d) -> double {
if (d < epsilon) {
return 0;
} else {
return d;
}
});
}
You can capture by both reference and value, which you can specify using &
and =
respectively:
[&epsilon]
capture by reference[&]
captures all variables used in the lambda by reference[=]
captures all variables used in the lambda by value[&, epsilon]
captures variables like with [&], but epsilon by value[=, &epsilon]
captures variables like with [=], but epsilon by referenceThe generated operator()
is const
by default, with the implication that captures will be const
when you access them by default. This has the effect that each call with the same input would produce the same result, however you can mark the lambda as mutable
to request that the operator()
that is produced is not const
.
I have found another reason: different versions used for icons in toolbox and references in the project. After inserting the objects in some form, the error started.
There are several ways. One way is to use save()
to save the exact object. e.g. for data frame foo
:
save(foo,file="data.Rda")
Then load it with:
load("data.Rda")
You could also use write.table()
or something like that to save the table in plain text, or dput()
to obtain R code to reproduce the table.
Write below code
ImageView yourImageView = (ImageView) findViewById(R.id.yourImageView);
Bitmap bitmap = ((BitmapDrawable)yourImageView.getDrawable()).getBitmap();
With the introduction of C# 6 (in VS 2015), you can now have get
-only automatic properties, in which the implicit backing field is readonly
(i.e. values can be assigned in the constructor but not elsewhere):
public string Name { get; }
public Customer(string name) // Constructor
{
Name = name;
}
private void SomeFunction()
{
Name = "Something Else"; // Compile-time error
}
And you can now also initialise properties (with or without a setter) inline:
public string Name { get; } = "Boris";
Referring back to the question, this gives you the advantages of option 2 (public member is a property, not a field) with the brevity of option 1.
Unfortunately, it doesn't provide a guarantee of immutability at the level of the public interface (as in @CodesInChaos's point about self-documentation), because to a consumer of the class, having no setter is indistinguishable from having a private setter.
You can try the code below, it works perfectly.
Here we share to some specific apps, that are Facebook, Messenger, Twitter, Google Plus and Gmail.
public void shareIntentSpecificApps() {
List<Intent> intentShareList = new ArrayList<Intent>();
Intent shareIntent = new Intent();
shareIntent.setAction(Intent.ACTION_SEND);
shareIntent.setType("text/plain");
List<ResolveInfo> resolveInfoList = getPackageManager().queryIntentActivities(shareIntent, 0);
for (ResolveInfo resInfo : resolveInfoList) {
String packageName = resInfo.activityInfo.packageName;
String name = resInfo.activityInfo.name;
Log.d(TAG, "Package Name : " + packageName);
Log.d(TAG, "Name : " + name);
if (packageName.contains("com.facebook") ||
packageName.contains("com.twitter.android") ||
packageName.contains("com.google.android.apps.plus") ||
packageName.contains("com.google.android.gm")) {
if (name.contains("com.twitter.android.DMActivity")) {
continue;
}
Intent intent = new Intent();
intent.setComponent(new ComponentName(packageName, name));
intent.setAction(Intent.ACTION_SEND);
intent.setType("text/plain");
intent.putExtra(Intent.EXTRA_SUBJECT, "Your Subject");
intent.putExtra(Intent.EXTRA_TEXT, "Your Content");
intentShareList.add(intent);
}
}
if (intentShareList.isEmpty()) {
Toast.makeText(MainActivity.this, "No apps to share !", Toast.LENGTH_SHORT).show();
} else {
Intent chooserIntent = Intent.createChooser(intentShareList.remove(0), "Share via");
chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, intentShareList.toArray(new Parcelable[]{}));
startActivity(chooserIntent);
}
}
I fixed a similar error by adding the json dataType like so:
$.ajax({
type: "POST",
url: "someUrl",
dataType: "json",
data: {
varname1 : "varvalue1",
varname2 : "varvalue2"
},
success: function (data) {
$.each(data, function (varname, varvalue){
...
});
}
});
And in my controller I had to use double quotes around any strings like so (note: they have to be escaped in java):
@RequestMapping(value = "/someUrl", method=RequestMethod.POST)
@ResponseBody
public String getJsonData(@RequestBody String parameters) {
// parameters = varname1=varvalue1&varname2=varvalue2
String exampleData = "{\"somename1\":\"somevalue1\",\"somename2\":\"somevalue2\"}";
return exampleData;
}
So, you could try using double quotes around your numbers if they are being used as strings (and remove that last comma):
[{"id":"50","name":"SEO"},{"id":"22","name":"LPO"}]
bool === tool ? bool : tool
if you want the value to hold true if tool
(another boolean) has the same value
$('div').attr('style', '');
or
$('div').removeAttr('style');
(From Andres's Answer)
To make this a little smaller, try this:
$('div[style]').removeAttr('style');
This should speed it up a little because it checks that the divs have the style attribute.
Either way, this might take a little while to process if you have a large amount of divs, so you might want to consider other methods than javascript.
You can use :+
to append element to array and +:
to prepend it:
0 +: array :+ 4
should produce:
res3: Array[Int] = Array(0, 1, 2, 3, 4)
It's the same as with any other implementation of Seq
.
Just follow these Steps :
If you want the contents of, say, C1 to mirror the contents of cell A1, you just need to set the formula in C1 to =A1. From this point forward, anything you type in A1 will show up in C1 as well.
To Link Multiple Cells in Excel From Another Worksheet :
Step 1
Click the worksheet tab at the bottom of the screen that contains a range of precedent cells to which you want to link. A range is a block or group of adjacent cells. For example, assume you want to link a range of blank cells in “Sheet1” to a range of precedent cells in “Sheet2.” Click the “Sheet2” tab.
Step 2
Determine the precedent range’s width in columns and height in rows. In this example, assume cells A1 through A4 on “Sheet2” contain a list of numbers 1, 2, 3 and 4, respectively, which will be your precedent cells. This precedent range is one column wide by four rows high.
Step 3
Click the worksheet tab at the bottom of the screen that contains the blank cells in which you will insert a link. In this example, click the “Sheet1” tab.
Step 4
Select the range of blank cells you want to link to the precedent cells. This range must be the same size as the precedent range, but can be in a different location on the worksheet. Click and hold the mouse button on the top left cell of the range, drag the mouse cursor to the bottom right cell in the range and release the mouse button to select the range. In this example, assume you want to link cells C1 through C4 to the precedent range. Click and hold on cell C1, drag the mouse to cell C4 and release the mouse to highlight the range.
Step 5
Type “=,” the worksheet name containing the precedent cells, “!,” the top left cell of the precedent range, “:” and the bottom right cell of the precedent range. Press “Ctrl,” “Shift” and “Enter” simultaneously to complete the array formula. Each dependent cell is now linked to the cell in the precedent range that’s in the same respective location within the range. In this example, type “=Sheet2!A1:A4” and press “Ctrl,” “Shift” and “Enter” simultaneously. Cells C1 through C4 on “Sheet1” now contain the array formula “{=Sheet2!A1:A4}” surrounded by curly brackets, and show the same data as the precedent cells in “Sheet2.”
Good Luck !!!
You have two easy ways to do this. Jay has covered the accurate way of checking from the center of the ball.
The easier way is to use a rectangle bounding box, set the size of your box to be 80% the size of the ball, and you'll simulate collision pretty well.
Add a method to your ball class:
public Rectangle getBoundingRect()
{
int ballHeight = (int)Ball.Height * 0.80f;
int ballWidth = (int)Ball.Width * 0.80f;
int x = Ball.X - ballWidth / 2;
int y = Ball.Y - ballHeight / 2;
return new Rectangle(x,y,ballHeight,ballWidth);
}
Then, in your loop:
// Checks every ball against every other ball.
// For best results, split it into quadrants like Ryan suggested.
// I didn't do that for simplicity here.
for (int i = 0; i < balls.count; i++)
{
Rectangle r1 = balls[i].getBoundingRect();
for (int k = 0; k < balls.count; k++)
{
if (balls[i] != balls[k])
{
Rectangle r2 = balls[k].getBoundingRect();
if (r1.Intersects(r2))
{
// balls[i] collided with balls[k]
}
}
}
}
There is another scenario where this issue reproduces (as in my case). When THE CLIENT REQUEST doesn't contain the right extension on the url, the controller can't identify the desired result format.
For example: the controller is set to respond_to :json
(as a single option, without a HTML response)- while the client call is set to /reservations
instead of /reservations.json
.
Bottom line, change the client call to /reservations.json
.
Change the checkboxes so that the name includes the index inside the brackets:
<input type="checkbox" class="checkbox_veh" id="checkbox_addveh<?php echo $i; ?>" <?php if ($vehicle_feature[$i]->check) echo "checked"; ?> name="feature[<?php echo $i; ?>]" value="<?php echo $vehicle_feature[$i]->id; ?>">
The checkboxes that aren't checked are never submitted. The boxes that are checked get submitted, but they get numbered consecutively from 0, and won't have the same indexes as the other corresponding input fields.
Router Link
routerLink with brackets and none - simple explanation.
The difference between routerLink= and [routerLink] is mostly like relative and absolute path.
Similar to a href you may want to navigate to ./about.html or https://your-site.com/about.html.
When you use without brackets then you navigate relative and without params;
my-app.com/dashboard/client
"jumping" from my-app.com/dashboard to my-app.com/dashboard/client
<a routerLink="client/{{ client.id }}" .... rest the same
When you use routerLink with brackets then you execute app to navigate absolute and you can add params how is the puzzle of your new link
first of all it will not include the "jump" from dashboard/ to dashboard/client/client-id and bring you data of client/client-id which is more helpful for EDIT CLIENT
<a [routerLink]="['/client', client.id]" ... rest the same
The absolute way or brackets routerLink require additional set up of you components and app.routing.module.ts
The code without error will "tell you more/what is the purpose of []" when you make the test. Just check this with or without []. Than you may experiments with selectors which - as mention above - helps with dynamics routing.
See whats the routerLink construct
If you are on windows and having problem either changing environment variables or mklink
because of insufficient privileges, an easy solution to your problem is to start git batch in another location.
Just right click on Git Bash.exe, click properties and change the "Start in" property to c:\my_configuration_files\
.
Basic Authentication use base 64 Encoding for generating cryptographic string which contains the information of username and password.
Digest Access Authentication uses the hashing methodologies to generate the cryptographic result
Add height & width properties to your .css file.
An optional in Swift is a type that can hold either a value or no value. Optionals are written by appending a ?
to any type:
var name: String? = "Bertie"
Optionals (along with Generics) are one of the most difficult Swift concepts to understand. Because of how they are written and used, it's easy to get a wrong idea of what they are. Compare the optional above to creating a normal String:
var name: String = "Bertie" // No "?" after String
From the syntax it looks like an optional String is very similar to an ordinary String. It's not. An optional String is not a String with some "optional" setting turned on. It's not a special variety of String. A String and an optional String are completely different types.
Here's the most important thing to know: An optional is a kind of container. An optional String is a container which might contain a String. An optional Int is a container which might contain an Int. Think of an optional as a kind of parcel. Before you open it (or "unwrap" in the language of optionals) you won't know if it contains something or nothing.
You can see how optionals are implemented in the Swift Standard Library by typing "Optional" into any Swift file and ?-clicking on it. Here's the important part of the definition:
enum Optional<Wrapped> {
case none
case some(Wrapped)
}
Optional is just an enum
which can be one of two cases: .none
or .some
. If it's .some
, there's an associated value which, in the example above, would be the String
"Hello". An optional uses Generics to give a type to the associated value. The type of an optional String isn't String
, it's Optional
, or more precisely Optional<String>
.
Everything Swift does with optionals is magic to make reading and writing code more fluent. Unfortunately this obscures the way it actually works. I'll go through some of the tricks later.
Note: I'll be talking about optional variables a lot, but it's fine to create optional constants too. I mark all variables with their type to make it easier to understand type types being created, but you don't have to in your own code.
To create an optional, append a ?
after the type you wish to wrap. Any type can be optional, even your own custom types. You can't have a space between the type and the ?
.
var name: String? = "Bob" // Create an optional String that contains "Bob"
var peter: Person? = Person() // An optional "Person" (custom type)
// A class with a String and an optional String property
class Car {
var modelName: String // must exist
var internalName: String? // may or may not exist
}
You can compare an optional to nil
to see if it has a value:
var name: String? = "Bob"
name = nil // Set name to nil, the absence of a value
if name != nil {
print("There is a name")
}
if name == nil { // Could also use an "else"
print("Name has no value")
}
This is a little confusing. It implies that an optional is either one thing or another. It's either nil or it's "Bob". This is not true, the optional doesn't transform into something else. Comparing it to nil is a trick to make easier-to-read code. If an optional equals nil, this just means that the enum is currently set to .none
.
If you try to set a non-optional variable to nil, you'll get an error.
var red: String = "Red"
red = nil // error: nil cannot be assigned to type 'String'
Another way of looking at optionals is as a complement to normal Swift variables. They are a counterpart to a variable which is guaranteed to have a value. Swift is a careful language that hates ambiguity. Most variables are define as non-optionals, but sometimes this isn't possible. For example, imagine a view controller which loads an image either from a cache or from the network. It may or may not have that image at the time the view controller is created. There's no way to guarantee the value for the image variable. In this case you would have to make it optional. It starts as nil
and when the image is retrieved, the optional gets a value.
Using an optional reveals the programmers intent. Compared to Objective-C, where any object could be nil, Swift needs you to be clear about when a value can be missing and when it's guaranteed to exist.
An optional String
cannot be used in place of an actual String
. To use the wrapped value inside an optional, you have to unwrap it. The simplest way to unwrap an optional is to add a !
after the optional name. This is called "force unwrapping". It returns the value inside the optional (as the original type) but if the optional is nil
, it causes a runtime crash. Before unwrapping you should be sure there's a value.
var name: String? = "Bob"
let unwrappedName: String = name!
print("Unwrapped name: \(unwrappedName)")
name = nil
let nilName: String = name! // Runtime crash. Unexpected nil.
Because you should always check for nil before unwrapping and using an optional, this is a common pattern:
var mealPreference: String? = "Vegetarian"
if mealPreference != nil {
let unwrappedMealPreference: String = mealPreference!
print("Meal: \(unwrappedMealPreference)") // or do something useful
}
In this pattern you check that a value is present, then when you are sure it is, you force unwrap it into a temporary constant to use. Because this is such a common thing to do, Swift offers a shortcut using "if let". This is called "optional binding".
var mealPreference: String? = "Vegetarian"
if let unwrappedMealPreference: String = mealPreference {
print("Meal: \(unwrappedMealPreference)")
}
This creates a temporary constant (or variable if you replace let
with var
) whose scope is only within the if's braces. Because having to use a name like "unwrappedMealPreference" or "realMealPreference" is a burden, Swift allows you to reuse the original variable name, creating a temporary one within the bracket scope
var mealPreference: String? = "Vegetarian"
if let mealPreference: String = mealPreference {
print("Meal: \(mealPreference)") // separate from the other mealPreference
}
Here's some code to demonstrate that a different variable is used:
var mealPreference: String? = "Vegetarian"
if var mealPreference: String = mealPreference {
print("Meal: \(mealPreference)") // mealPreference is a String, not a String?
mealPreference = "Beef" // No effect on original
}
// This is the original mealPreference
print("Meal: \(mealPreference)") // Prints "Meal: Optional("Vegetarian")"
Optional binding works by checking to see if the optional equals nil. If it doesn't, it unwraps the optional into the provided constant and executes the block. In Xcode 8.3 and later (Swift 3.1), trying to print an optional like this will cause a useless warning. Use the optional's debugDescription
to silence it:
print("\(mealPreference.debugDescription)")
Optionals have two use cases:
Some concrete examples:
middleName
or spouse
in a Person
classweak
properties in classes. The thing they point to can be set to nil
at any timeBoolean
Optionals don't exist in Objective-C but there is an equivalent concept, returning nil. Methods that can return an object can return nil instead. This is taken to mean "the absence of a valid object" and is often used to say that something went wrong. It only works with Objective-C objects, not with primitives or basic C-types (enums, structs). Objective-C often had specialized types to represent the absence of these values (NSNotFound
which is really NSIntegerMax
, kCLLocationCoordinate2DInvalid
to represent an invalid coordinate, -1
or some negative value are also used). The coder has to know about these special values so they must be documented and learned for each case. If a method can't take nil
as a parameter, this has to be documented. In Objective-C, nil
was a pointer just as all objects were defined as pointers, but nil
pointed to a specific (zero) address. In Swift, nil
is a literal which means the absence of a certain type.
nil
You used to be able to use any optional as a Boolean
:
let leatherTrim: CarExtras? = nil
if leatherTrim {
price = price + 1000
}
In more recent versions of Swift you have to use leatherTrim != nil
. Why is this? The problem is that a Boolean
can be wrapped in an optional. If you have Boolean
like this:
var ambiguous: Boolean? = false
it has two kinds of "false", one where there is no value and one where it has a value but the value is false
. Swift hates ambiguity so now you must always check an optional against nil
.
You might wonder what the point of an optional Boolean
is? As with other optionals the .none
state could indicate that the value is as-yet unknown. There might be something on the other end of a network call which takes some time to poll. Optional Booleans are also called "Three-Value Booleans"
Swift uses some tricks to allow optionals to work. Consider these three lines of ordinary looking optional code;
var religiousAffiliation: String? = "Rastafarian"
religiousAffiliation = nil
if religiousAffiliation != nil { ... }
None of these lines should compile.
String
the types are differentI'll go through some of the implementation details of optionals that allow these lines to work.
Using ?
to create an optional is syntactic sugar, enabled by the Swift compiler. If you want to do it the long way, you can create an optional like this:
var name: Optional<String> = Optional("Bob")
This calls Optional
's first initializer, public init(_ some: Wrapped)
, which infers the optional's associated type from the type used within the parentheses.
The even longer way of creating and setting an optional:
var serialNumber:String? = Optional.none
serialNumber = Optional.some("1234")
print("\(serialNumber.debugDescription)")
nil
You can create an optional with no initial value, or create one with the initial value of nil
(both have the same outcome).
var name: String?
var name: String? = nil
Allowing optionals to equal nil
is enabled by the protocol ExpressibleByNilLiteral
(previously named NilLiteralConvertible
). The optional is created with Optional
's second initializer, public init(nilLiteral: ())
. The docs say that you shouldn't use ExpressibleByNilLiteral
for anything except optionals, since that would change the meaning of nil in your code, but it's possible to do it:
class Clint: ExpressibleByNilLiteral {
var name: String?
required init(nilLiteral: ()) {
name = "The Man with No Name"
}
}
let clint: Clint = nil // Would normally give an error
print("\(clint.name)")
The same protocol allows you to set an already-created optional to nil
. Although it's not recommended, you can use the nil literal initializer directly:
var name: Optional<String> = Optional(nilLiteral: ())
nil
Optionals define two special "==" and "!=" operators, which you can see in the Optional
definition. The first ==
allows you to check if any optional is equal to nil. Two different optionals which are set to .none will always be equal if the associated types are the same. When you compare to nil, behind the scenes Swift creates an optional of the same associated type, set to .none then uses that for the comparison.
// How Swift actually compares to nil
var tuxedoRequired: String? = nil
let temp: Optional<String> = Optional.none
if tuxedoRequired == temp { // equivalent to if tuxedoRequired == nil
print("tuxedoRequired is nil")
}
The second ==
operator allows you to compare two optionals. Both have to be the same type and that type needs to conform to Equatable
(the protocol which allows comparing things with the regular "==" operator). Swift (presumably) unwraps the two values and compares them directly. It also handles the case where one or both of the optionals are .none
. Note the distinction between comparing to the nil
literal.
Furthermore, it allows you to compare any Equatable
type to an optional wrapping that type:
let numberToFind: Int = 23
let numberFromString: Int? = Int("23") // Optional(23)
if numberToFind == numberFromString {
print("It's a match!") // Prints "It's a match!"
}
Behind the scenes, Swift wraps the non-optional as an optional before the comparison. It works with literals too (if 23 == numberFromString {
)
I said there are two ==
operators, but there's actually a third which allow you to put nil
on the left-hand side of the comparison
if nil == name { ... }
There is no Swift convention for naming optional types differently from non-optional types. People avoid adding something to the name to show that it's an optional (like "optionalMiddleName", or "possibleNumberAsString") and let the declaration show that it's an optional type. This gets difficult when you want to name something to hold the value from an optional. The name "middleName" implies that it's a String type, so when you extract the String value from it, you can often end up with names like "actualMiddleName" or "unwrappedMiddleName" or "realMiddleName". Use optional binding and reuse the variable name to get around this.
From "The Basics" in the Swift Programming Language:
Swift also introduces optional types, which handle the absence of a value. Optionals say either “there is a value, and it equals x” or “there isn’t a value at all”. Optionals are similar to using nil with pointers in Objective-C, but they work for any type, not just classes. Optionals are safer and more expressive than nil pointers in Objective-C and are at the heart of many of Swift’s most powerful features.
Optionals are an example of the fact that Swift is a type safe language. Swift helps you to be clear about the types of values your code can work with. If part of your code expects a String, type safety prevents you from passing it an Int by mistake. This enables you to catch and fix errors as early as possible in the development process.
To finish, here's a poem from 1899 about optionals:
Yesterday upon the stair
I met a man who wasn’t there
He wasn’t there again today
I wish, I wish he’d go away
Antigonish
In newer versions of CMake you can set compiler and linker flags for a single target with target_compile_options
and target_link_libraries
respectively (yes, the latter sets linker options too):
target_compile_options(first-test PRIVATE -fexceptions)
The advantage of this method is that you can control propagation of options to other targets that depend on this one via PUBLIC
and PRIVATE
.
As of CMake 3.13 you can also use target_link_options
to add linker options which makes the intent more clear.
Try these steps:
Clean the solution.
Build every project separately.
Resolve any errors if found (sometimes, VS is not showing errors until you build it separately).
Then try to run migration again.
PS> Add-Type -Assembly Microsoft.VisualBasic
PS> [Microsoft.VisualBasic.Information]::IsNumeric(1.5)
True
http://msdn.microsoft.com/en-us/library/microsoft.visualbasic.information.isnumeric.aspx
A valid reason for wanting to free memory from any programm (java or not ) is to make more memory available to other programms on operating system level. If my java application is using 250MB I may want to force it down to 1MB and make the 249MB available to other apps.
I needed to apply a translation to the Ok and Cancel buttons. I modified the code to except dynamic text (calls my translation function)
$.extend({_x000D_
confirm: function(message, title, okAction) {_x000D_
$("<div></div>").dialog({_x000D_
// Remove the closing 'X' from the dialog_x000D_
open: function(event, ui) { $(".ui-dialog-titlebar-close").hide(); },_x000D_
width: 500,_x000D_
buttons: [{_x000D_
text: localizationInstance.translate("Ok"),_x000D_
click: function () {_x000D_
$(this).dialog("close");_x000D_
okAction();_x000D_
}_x000D_
},_x000D_
{_x000D_
text: localizationInstance.translate("Cancel"),_x000D_
click: function() {_x000D_
$(this).dialog("close");_x000D_
}_x000D_
}],_x000D_
close: function(event, ui) { $(this).remove(); },_x000D_
resizable: false,_x000D_
title: title,_x000D_
modal: true_x000D_
}).text(message);_x000D_
}_x000D_
});
_x000D_
As you already hinted in your question, your code creates all promises synchronously. Instead they should only be created at the time the preceding one resolves.
Secondly, each promise that is created with new Promise
needs to be resolved with a call to resolve
(or reject
). This should be done when the timer expires. That will trigger any then
callback you would have on that promise. And such a then
callback (or await
) is a necessity in order to implement the chain.
With those ingredients, there are several ways to perform this asynchronous chaining:
With a for
loop that starts with an immediately resolving promise
With Array#reduce
that starts with an immediately resolving promise
With a function that passes itself as resolution callback
With ECMAScript2017's async
/ await
syntax
With ECMAScript2020's for await...of
syntax
See a snippet and comments for each of these options below.
for
You can use a for
loop, but you must make sure it doesn't execute new Promise
synchronously. Instead you create an initial immediately resolving promise, and then chain new promises as the previous ones resolve:
for (let i = 0, p = Promise.resolve(); i < 10; i++) {
p = p.then(_ => new Promise(resolve =>
setTimeout(function () {
console.log(i);
resolve();
}, Math.random() * 1000)
));
}
_x000D_
reduce
This is just a more functional approach to the previous strategy. You create an array with the same length as the chain you want to execute, and start out with an immediately resolving promise:
[...Array(10)].reduce( (p, _, i) =>
p.then(_ => new Promise(resolve =>
setTimeout(function () {
console.log(i);
resolve();
}, Math.random() * 1000)
))
, Promise.resolve() );
_x000D_
This is probably more useful when you actually have an array with data to be used in the promises.
Here we create a function and call it immediately. It creates the first promise synchronously. When it resolves, the function is called again:
(function loop(i) {
if (i < 10) new Promise((resolve, reject) => {
setTimeout( () => {
console.log(i);
resolve();
}, Math.random() * 1000);
}).then(loop.bind(null, i+1));
})(0);
_x000D_
This creates a function named loop
, and at the very end of the code you can see it gets called immediately with argument 0. This is the counter, and the i argument. The function will create a new promise if that counter is still below 10, otherwise the chaining stops.
The call to resolve()
will trigger the then
callback which will call the function again. loop.bind(null, i+1)
is just a different way of saying _ => loop(i+1)
.
async
/await
Modern JS engines support this syntax:
(async function loop() {
for (let i = 0; i < 10; i++) {
await new Promise(resolve => setTimeout(resolve, Math.random() * 1000));
console.log(i);
}
})();
_x000D_
It may look strange, as it seems like the new Promise()
calls are executed synchronously, but in reality the async
function returns when it executes the first await
. Every time an awaited promise resolves, the function's running context is restored, and proceeds after the await
, until it encounters the next one, and so it continues until the loop finishes.
As it may be a common thing to return a promise based on a timeout, you could create a separate function for generating such a promise. This is called promisifying a function, in this case setTimeout
. It may improve the readability of the code:
const delay = ms => new Promise(resolve => setTimeout(resolve, ms));
(async function loop() {
for (let i = 0; i < 10; i++) {
await delay(Math.random() * 1000);
console.log(i);
}
})();
_x000D_
for await...of
With EcmaScript 2020, the for await...of
found its way to modern JavaScript engines. Although it does not really reduce code in this case, it allows to isolate the definition of the random interval chain from the actual iteration of it:
const delay = ms => new Promise(resolve => setTimeout(resolve, ms));
async function * randomDelays(count ,max) {
for (let i = 0; i < count; i++) yield delay(Math.random() * max).then(() => i);
}
(async function loop() {
for await (let i of randomDelays(10, 1000)) console.log(i);
})();
_x000D_
I have also used following link as others have suggested you for bluetooth communication.
http://developer.android.com/guide/topics/connectivity/bluetooth.html
The thing is all you need is a class BluetoothChatService.java
this class has following threads:
Now when you call start function of the BluetoothChatService like:
mChatService.start();
It starts accept thread which means it will start looking for connection.
Now when you call
mChatService.connect(<deviceObject>,false/true);
Here first argument is device object that you can get from paired devices list or when you scan for devices you will get all the devices in range you can pass that object to this function and 2nd argument is a boolean to make secure or insecure connection.
connect
function will start connecting thread which will look for any device which is running accept thread.
When such a device is found both accept thread and connecting thread will call connected function in BluetoothChatService:
connected(mmSocket, mmDevice, mSocketType);
this method starts connected thread in both the devices:
Using this socket object connected thread obtains the input and output stream to the other device.
And calls read
function on inputstream in a while loop so that it's always trying read from other device so that whenever other device send a message this read function returns that message.
BluetoothChatService also has a write
method which takes byte[]
as input and calls write method on connected thread.
mChatService.write("your message".getByte());
write method in connected thread just write this byte data to outputsream of the other device.
public void write(byte[] buffer) {
try {
mmOutStream.write(buffer);
// Share the sent message back to the UI Activity
// mHandler.obtainMessage(
// BluetoothGameSetupActivity.MESSAGE_WRITE, -1, -1,
// buffer).sendToTarget();
} catch (IOException e) {
Log.e(TAG, "Exception during write", e);
}
}
Now to communicate between two devices just call write function on mChatService and handle the message that you will receive on the other device.
as the the accepted answer mentioned, you can enlarge the fontSize css attribute of the element in DOM one by one, the following code for your reference.
<script>
var factor = 1.2;
var all = document.getElementsByTagName("*");
for (var i=0, max=all.length; i < max; i++) {
var style = window.getComputedStyle(all[i]);
var fontSize = style.getPropertyValue('font-size');
if(fontSize){
all[i].style.fontSize=(parseFloat(fontSize)*factor)+"px";
}
if(all[i].nodeName === "IMG"){
var width=style.getPropertyValue('width');
var height=style.getPropertyValue('height');
all[i].style.height = (parseFloat(height)*factor)+"px";
all[i].style.width = (parseFloat(width)*factor)+"px";
}
}
</script>
// looking for that last hex?
org.joda.DateTime@57110da6
If you're looking into the hashcode
Java types when you do a .toString()
on an object the underlying code is this:
Integer.toHexString(hashCode())
To avoid regex hell you could find your first match, chop off a chunk then attempt to find the next one on the substring. In C# this looks something like this, sorry I've not ported it over to JavaScript for you.
long count = 0;
var remainder = data;
Match match = null;
do
{
match = _rgx.Match(remainder);
if (match.Success)
{
count++;
remainder = remainder.Substring(match.Index + 1, remainder.Length - (match.Index+1));
}
} while (match.Success);
return count;
You can also install any of the Hardware IO Tools without installing XCode itself. Simply visit Apple's Download Center and search for "Hardware IO".
@balalakshmi mentioned about the correct authentication settings. Authentication is only half of the problem, the other half is authorization.
If you're using Forms Authentication and standard controls like <asp:Login>
there are a couple of things you'll need to do to ensure that only your authenticated users can access secured pages.
In web.config
, under the <system.web>
section you'll need to disable anonymous access by default:
<authorization>
<deny users="?" />
</authorization>
Any pages that will be accessed anonymously (such as the Login.aspx page itself) will need to have an override that re-allows anonymous access. This requires a <location>
element and must be located at the <configuration>
level (outside the <system.web>
section), like this:
<!-- Anonymous files -->
<location path="Login.aspx">
<system.web>
<authorization>
<allow users="*" />
</authorization>
</system.web>
</location>
Note that you'll also need to allow anonymous access to any style sheets or scripts that are used by the anonymous pages:
<!-- Anonymous folders -->
<location path="styles">
<system.web>
<authorization>
<allow users="*" />
</authorization>
</system.web>
</location>
Be aware that the location's path
attribute is relative to the web.config
folder and cannot have a ~/
prefix, unlike most other path-type configuration attributes.
Since rows already exist in the table, the ALTER
statement is trying to insert NULL
into the newly created column for all of the existing rows. You would have to add the column as allowing NULL
, then fill the column with the values you want, and then set it to NOT NULL
afterwards.
If between two remote mongod instances, use
{ cloneCollection: "<collection>", from: "<hostname>", query: { <query> }, copyIndexes: <true|false> }
See http://docs.mongodb.org/manual/reference/command/cloneCollection/
$( "button" ).on( "click", function(event) {_x000D_
_x000D_
alert( $( this ).html() );_x000D_
console.log( event.target );_x000D_
_x000D_
} );
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>_x000D_
_x000D_
<button>test 1</button>_x000D_
<button>test 2</button>
_x000D_
Steps
Search IIS In Visual Studio 2015
Chose (Use the 64 bit of version of IIS Express for web site and project
)
About this solution, we could just create a directive and attach it to the DOM element that has to get the focus when a given condition is satisfied. By following this approach we avoid coupling controller to DOM element ID's.
Sample code directive:
gbndirectives.directive('focusOnCondition', ['$timeout',
function ($timeout) {
var checkDirectivePrerequisites = function (attrs) {
if (!attrs.focusOnCondition && attrs.focusOnCondition != "") {
throw "FocusOnCondition missing attribute to evaluate";
}
}
return {
restrict: "A",
link: function (scope, element, attrs, ctrls) {
checkDirectivePrerequisites(attrs);
scope.$watch(attrs.focusOnCondition, function (currentValue, lastValue) {
if(currentValue == true) {
$timeout(function () {
element.focus();
});
}
});
}
};
}
]);
A possible usage
.controller('Ctrl', function($scope) {
$scope.myCondition = false;
// you can just add this to a radiobutton click value
// or just watch for a value to change...
$scope.doSomething = function(newMyConditionValue) {
// do something awesome
$scope.myCondition = newMyConditionValue;
};
});
HTML
<input focus-on-condition="myCondition">
ngStyle
accepts a map:
$scope.myStyle = {
"width" : "900px",
"background" : "red"
};
If your code doesn't cross filesystem boundaries, i.e. you're just working with one filesystem, then use java.io.File.separator
.
This will, as explained, get you the default separator for your FS. As Bringer128 explained, System.getProperty("file.separator")
can be overriden via command line options and isn't as type safe as java.io.File.separator
.
The last one, java.nio.file.FileSystems.getDefault().getSeparator();
was introduced in Java 7, so you might as well ignore it for now if you want your code to be portable across older Java versions.
So, every one of these options is almost the same as others, but not quite. Choose one that suits your needs.
The following points help you in deciding in which situations one should use Comparable and in which Comparator:
1) Code Availabilty
2) Single Versus Multiple Sorting Criteria
3) Arays.sort() and Collection.sort()
4) As keys in SortedMap and SortedSet
5) More Number of classes Versus flexibility
6) Interclass comparisions
7) Natural Order
For more detailed article you can refer When to use comparable and when to use comparator
My solution:
protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
myobj.myconnection();// connection created
string mystr = "Delete table_name where water_id= '" + GridView1.DataKeys[e.RowIndex].Value + "'";// query
sqlcmd = new SqlCommand(mystr, myobj.mycon);
sqlcmd.ExecuteNonQuery();
fillgrid();
}
not Error:
JSONObject json1 = getJsonX();
Error:
JSONObject json2 = null;
if(x == y)
json2 = getJSONX();
Error: Local variable statement defined in an enclosing scope must be final or effectively final.
But you can write:
JSONObject json2 = (x == y) ? json2 = getJSONX() : null;
They are not managed, but measured and possibly limited (see getrlimit
system call, also on getrlimit(2)).
RSS means resident set size (the part of your virtual address space sitting in RAM).
You can query the virtual address space of process 1234 using proc(5) with cat /proc/1234/maps
and its status (including memory consumption) thru cat /proc/1234/status
Modules Preconditions:
The IIS core engine uses preconditions to determine when to enable a particular module. Performance reasons, for example, might determine that you only want to execute managed modules for requests that also go to a managed handler. The precondition in the following example (
precondition="managedHandler"
) only enables the forms authentication module for requests that are also handled by a managed handler, such as requests to .aspx or .asmx files:<add name="FormsAuthentication" type="System.Web.Security.FormsAuthenticationModule" preCondition="managedHandler" />
If you remove the attribute
precondition="managedHandler"
, Forms Authentication also applies to content that is not served by managed handlers, such as .html, .jpg, .doc, but also for classic ASP (.asp) or PHP (.php) extensions. See "How to Take Advantage of IIS Integrated Pipeline" for an example of enabling ASP.NET modules to run for all content.You can also use a shortcut to enable all managed (ASP.NET) modules to run for all requests in your application, regardless of the "
managedHandler
" precondition.To enable all managed modules to run for all requests without configuring each module entry to remove the "
managedHandler
" precondition, use therunAllManagedModulesForAllRequests
property in the<modules>
section:<modules runAllManagedModulesForAllRequests="true" />
When you use this property, the "
managedHandler
" precondition has no effect and all managed modules run for all requests.
Copied from IIS Modules Overview: Preconditions
You weren't far from the result! This does it:
awk '{NF--; print $NF}' file
This decrements the number of fields in one, so that $NF
contains the former penultimate.
Let's generate some numbers and print them on groups of 5:
$ seq 12 | xargs -n5
1 2 3 4 5
6 7 8 9 10
11 12
Let's print the penultimate on each line:
$ seq 12 | xargs -n5 | awk '{NF--; print $NF}'
4
9
11
Simply track your remote branches explicitly and a simple git pull
will do just what you want:
git branch -f remote_branch_name origin/remote_branch_name
git checkout remote_branch_name
The latter is a local operation.
Or even more fitting in with the GitHub documentation on forking:
git branch -f new_local_branch_name upstream/remote_branch_name
Some background: I went looking for exactly this question because I had to do something to retrieve content, but all I had available was an old version of python with inadequate SSL support. If you're on an older MacBook, you know what I'm talking about. In any case, curl
runs fine from a shell (I suspect it has modern SSL support linked in) so sometimes you want to do this without using requests
or urllib2
.
You can use the subprocess
module to execute curl
and get at the retrieved content:
import subprocess
// 'response' contains a []byte with the retrieved content.
// use '-s' to keep curl quiet while it does its job, but
// it's useful to omit that while you're still writing code
// so you know if curl is working
response = subprocess.check_output(['curl', '-s', baseURL % page_num])
Python 3's subprocess
module also contains .run()
with a number of useful options. I'll leave it to someone who is actually running python 3 to provide that answer.
The accepted answer provides the semantics on how to increase the limit, but as @voltrevo pointed out that warning is there for a reason and your code probably has a bug.
Consider the following buggy code:
//Assume Logger is a module that emits errors
var Logger = require('./Logger.js');
for (var i = 0; i < 11; i++) {
//BUG: This will cause the warning
//As the event listener is added in a loop
Logger.on('error', function (err) {
console.log('error writing log: ' + err)
});
Logger.writeLog('Hello');
}
Now observe the correct way of adding the listener:
//Good: event listener is not in a loop
Logger.on('error', function (err) {
console.log('error writing log: ' + err)
});
for (var i = 0; i < 11; i++) {
Logger.writeLog('Hello');
}
Search for similar issues in your code before changing the maxListeners (which is explained in other answers)
I know this this is a very old post but I've combined a few of the answers into a jQuery wrapper function that supports chaining. Hope it benefits someone:
$.fn.queueAddClass = function(className) {
this.queue('fx', function(next) {
$(this).addClass(className);
next();
});
return this;
};
And here's a removeClass wrapper:
$.fn.queueRemoveClass = function(className) {
this.queue('fx', function(next) {
$(this).removeClass(className);
next();
});
return this;
};
Now you can do stuff like this - wait 1sec, add .error
, wait 3secs, remove .error
:
$('#div').delay(1000).queueAddClass('error').delay(2000).queueRemoveClass('error');
I'm not sure it's good way to check it. What about case when user uses button "clear data" from settings? SharedPreferences will be cleared and you catch "first run" again. And it's a problem. I guess it's better idea to use InstallReferrerReceiver.
I had the same problem on macOS 10.14.5 using Xcode 10.2.1. After none of the solution here worked for me I restarted the Mac and this did the trick...
This because the input that the user inserts into the JOptionPane
is a String
and it is stored and returned as a String
.
Java cannot convert between strings and number by itself, you have to use specific functions, just use:
int ans = Integer.parseInt(JOptionPane.showInputDialog(...))
I had the same problem.
Here is a workaround
android:inputType="textNoSuggestions|textVisiblePassword"
android:maxLength="6"
Both nginx -t
and nginx -V
would print out the default nginx config file path.
$ nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
$ nginx -V
nginx version: nginx/1.11.1
built by gcc 4.9.2 (Debian 4.9.2-10)
built with OpenSSL 1.0.1k 8 Jan 2015
TLS SNI support enabled
configure arguments: --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf ...
If you want, you can get the config file by:
$ nginx -V 2>&1 | grep -o '\-\-conf-path=\(.*conf\)' | cut -d '=' -f2
/etc/nginx/nginx.conf
Even if you have loaded some other config file, they would still print out the default value.
ps aux
would show you the current loaded nginx config file.
$ ps aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 11 0.0 0.2 31720 2212 ? Ss Jul23 0:00 nginx: master process nginx -c /app/nginx.conf
So that you could actually get the config file by for example:
$ ps aux | grep "[c]onf" | awk '{print $(NF)}'
/app/nginx.conf
<style>
tags should be places within the <head>
element, and each added tag should be added to the bottom of the <head>
tag.
Using insertAdjacentHTML to inject a style tag into the document head tag:
document.head.insertAdjacentHTML("beforeend", `<style>body{background:red}</style>`)
_x000D_
$('<style>').text("body{background:red}").appendTo(document.head)
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
_x000D_
Add following at the bottom of your Info.plist
<key>ITSAppUsesNonExemptEncryption</key>
<false/>
I have Had the same issue and the only Solution i found was open Package manager> Select Microsoft and .Net as Package Source and You will install it..
Note: Calling a lifecycle method from another one is not a good practice. In below example I tried to achieve that your onNewIntent will be always called irrespective of your Activity type.
OnNewIntent() always get called for singleTop/Task activities except for the first time when activity is created. At that time onCreate is called providing to solution for few queries asked on this thread.
You can invoke onNewIntent always by putting it into onCreate method like
@Override
public void onCreate(Bundle savedState){
super.onCreate(savedState);
onNewIntent(getIntent());
}
@Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
//code
}
+---------------------------------------------------------------------------------------+--------------------------------------------------------------------------+
| TIMESTAMP | DATETIME |
+---------------------------------------------------------------------------------------+--------------------------------------------------------------------------+
| TIMESTAMP requires 4 bytes. | DATETIME requires 8 bytes. |
| Timestamp is the number of seconds that have elapsed since January 1, 1970 00:00 UTC. | DATETIME is a text displays 'YYYY-MM-DD HH:MM:SS' format. |
| TIMESTAMP supported range: ‘1970-01-01 00:00:01' UTC to ‘2038-01-19 03:14:07' UTC. | DATETIME supported range: ‘1000-01-01 00:00:00' to ‘9999-12-31 23:59:59' |
| TIMESTAMP during retrieval converted back to the current time zone. | DATETIME can not do this. |
| TIMESTAMP is used mostly for metadata i.e. row created/modified and audit purpose. | DATETIME is used mostly for user-data. |
+---------------------------------------------------------------------------------------+--------------------------------------------------------------------------+
Is there any solution like building a pdf file on file system in order to let the user download it?
Try setting responseType
of XMLHttpRequest
to blob
, substituting download
attribute at a
element for window.open
to allow download of response from XMLHttpRequest
as .pdf
file
var request = new XMLHttpRequest();
request.open("GET", "/path/to/pdf", true);
request.responseType = "blob";
request.onload = function (e) {
if (this.status === 200) {
// `blob` response
console.log(this.response);
// create `objectURL` of `this.response` : `.pdf` as `Blob`
var file = window.URL.createObjectURL(this.response);
var a = document.createElement("a");
a.href = file;
a.download = this.response.name || "detailPDF";
document.body.appendChild(a);
a.click();
// remove `a` following `Save As` dialog,
// `window` regains `focus`
window.onfocus = function () {
document.body.removeChild(a)
}
};
};
request.send();
If you don't want to use WMI, I can suggest systeminfo.exe. But, there may be a better way to do that.
(systeminfo | Select-String 'Total Physical Memory:').ToString().Split(':')[1].Trim()
I don't believe this is possible. I believe you have to clone that remote repo locally and perform git fetch
on it before you can issue a git log
against it.
SOLUTION: I make a directive for all inputs, number, text, or any, in the app, so you can input a value and change the event. Make for angular 6
import { Directive, ElementRef, HostListener, Input } from '@angular/core';
@Directive({
// tslint:disable-next-line:directive-selector
selector: 'input[inputType]'
})
export class InputTypeDirective {
constructor(private _el: ElementRef) {}
@Input() inputType: string;
// tipos: number, letter, cuit, tel
@HostListener('input', ['$event']) onInputChange(event) {
if (!event.data) {
return;
}
switch (this.inputType) {
case 'number': {
const initalValue = this._el.nativeElement.value;
this._el.nativeElement.value = initalValue.replace(/[^0-9]*/g, '');
if (initalValue !== this._el.nativeElement.value) {
event.stopPropagation();
}
break;
}
case 'text': {
const result = event.data.match(/[^a-zA-Z Ññ]*/g);
if (result[0] !== '') {
const initalValue = this._el.nativeElement.value;
this._el.nativeElement.value = initalValue.replace(
/[^a-zA-Z Ññ]*/g,
''
);
event.stopPropagation();
}
break;
}
case 'tel':
case 'cuit': {
const initalValue = this._el.nativeElement.value;
this._el.nativeElement.value = initalValue.replace(/[^0-9-]*/g, '');
if (initalValue !== this._el.nativeElement.value) {
event.stopPropagation();
}
}
}
}
}
HTML
<input matInput inputType="number" [formControlName]="field.name" [maxlength]="field.length" [placeholder]="field.label | translate" type="text" class="filter-input">
Set the value of the input
to null
on each onclick
event. This will reset the input
's value and trigger the onchange
event even if the same path is selected.
input.onclick = function () {
this.value = null;
};
input.onchange = function () {
alert(this.value);
};?
Here's a DEMO.
Note: It's normal if your file is prefixed with 'C:\fakepath\'. That's a security feature preventing JavaScript from knowing the file's absolute path. The browser still knows it internally.
Note x += y
is not the same as x = x + y
in some situations where an additional operator is included because of the operator precedence combined with the fact that the right hand side is always evaluated first, e.g.
>>> x = 2
>>> x += 2 and 1
>>> x
3
>>> x = 2
>>> x = x + 2 and 1
>>> x
1
Note the first case expand to:
>>> x = 2
>>> x = x + (2 and 1)
>>> x
3
You are more likely to encounter this in the 'real world' with other operators, e.g.
x *= 2 + 1
== x = x * (2 + 1)
!= x = x * 2 + 1
If you are willing to insert non-semantic nodes into your document, you can do this in a CSS-only IE-compatible manner by wrapping your divs in fake A tags.
<style type="text/css">
.content {
background: #ccc;
}
.fakeLink { /* This is to make the link not look like one */
cursor: default;
text-decoration: none;
color: #000;
}
a.fakeLink:hover .content {
background: #000;
color: #fff;
}
</style>
<div id="catestory">
<a href="#" onclick="return false();" class="fakeLink">
<div class="content">
<h2>some title here</h2>
<p>some content here</p>
</div>
</a>
<a href="#" onclick="return false();" class="fakeLink">
<div class="content">
<h2>some title here</h2>
<p>some content here</p>
</div>
</a>
<a href="#" onclick="return false();" class="fakeLink">
<div class="content">
<h2>some title here</h2>
<p>some content here</p>
</div>
</a>
</div>
settings.json
.settings.json
> Edit in settings.json
%APPDATA%\Code\User\settings.json
{
"terminal.integrated.shell.windows": "C:\\Windows\\System32\\cmd.exe",
"terminal.integrated.shellArgs.windows": ["/k nodevars.bat"]
}
If you already know what types to expect (for example, when a method returns a union type), then you can use type guards.
For example, for primitive types you can use a typeof guard:
if (typeof thing === "number") {
// Do stuff
}
For complex types you can use an instanceof guard:
if (thing instanceof Array) {
// Do stuff
}
1) do
svn revert . --recursive
2) parse output for errors like
"Failed to revert 'dir1/dir2' -- try updating instead."
3) call svn up for each of error directories:
svn up dir1/dir2
The answer really depends on how you are doing the INSERT
.
If you are specifying a SQL literal then you need to use the double-tick approach:
-- Direct insert
INSERT INTO Table1 (Column1) VALUES ('John''s')
-- Using a parameter, with a direct insert
DECLARE @Value varchar(50)
SET @Value = 'John''s'
INSERT INTO Table1 (Column1) VALUES (@Value)
-- Using a parameter, with dynamic SQL
DECLARE @Value varchar(50)
SET @Value = 'John''s'
EXEC sp_executesql 'INSERT INTO Table1 (Column1) VALUES (@p1)', '@p1 varchar(50)', @Value
If you are doing the INSERT from code, use parameters:
// Sample ADO.NET
using (SqlConnection conn = new SqlConnection(connectionString)) {
conn.Open();
using (SqlCommand command = conn.CreateCommand()) {
command.CommandText = "INSERT INTO Table1 (Column1) VALUES (@Value)";
command.Parameters.AddWithValue("@Value", "John's");
command.ExecuteNonQuery();
}
}
If your data contains user-input, direct or indirect, USE PARAMETERS. Parameters protect against SQL Injection attacks. Never ever build up dynamic SQL with user-input.
Just try this line:
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
after:
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
I just use
git remote update
git status
The latter then reports how many commits behind my local is (if any).
Then
git pull origin master
to bring my local up to date :)
Short form:
[s.pop(k) for k in list(s.keys()) if k not in keep]
As most of the answers suggest in order to maintain the conciseness we have to create a duplicate object be it a list
or dict
. This one creates a throw-away list
but deletes the keys in original dict
.
You have to add the following dependency to your build:
<dependency>
<groupId>org.openrdf.sesame</groupId>
<artifactId>sesame-rio-api</artifactId>
<version>2.7.2</version>
</dependency>
Furthermore i would suggest to take a deep look into the documentation about how to use the lib.
C11 standard draft
The C11 N1570 standard draft says:
7.24.2.1 "The memcpy function":
2 The memcpy function copies n characters from the object pointed to by s2 into the object pointed to by s1. If copying takes place between objects that overlap, the behavior is undefined.
7.24.2.2 "The memmove function":
2 The memmove function copies n characters from the object pointed to by s2 into the object pointed to by s1. Copying takes place as if the n characters from the object pointed to by s2 are first copied into a temporary array of n characters that does not overlap the objects pointed to by s1 and s2, and then the n characters from the temporary array are copied into the object pointed to by s1
Therefore, any overlap on memcpy
leads to undefined behavior, and anything can happen: bad, nothing or even good. Good is rare though :-)
memmove
however clearly says that everything happens as if an intermediate buffer is used, so clearly overlaps are OK.
C++ std::copy
is more forgiving however, and allows overlaps: Does std::copy handle overlapping ranges?
The accepted answer fires while scrolling through the messages, this avoids that.
You want a template like this.
<div #content>
<div #messages *ngFor="let message of messages">
{{message}}
</div>
</div>
Then you want to use a ViewChildren annotation to subscribe to new message elements being added to the page.
@ViewChildren('messages') messages: QueryList<any>;
@ViewChild('content') content: ElementRef;
ngAfterViewInit() {
this.scrollToBottom();
this.messages.changes.subscribe(this.scrollToBottom);
}
scrollToBottom = () => {
try {
this.content.nativeElement.scrollTop = this.content.nativeElement.scrollHeight;
} catch (err) {}
}
The answers to this question helped me find my problem, but my source was different, so hopefully this can shed light on someone finding this page searching for answers to the 'random' context crash:
I had specified a SharedPreferences object, and tried to instantiate it at it's class-level declaration, like so:
public class MyFragment extends FragmentActivity {
private SharedPreferences sharedPref =
PreferenceManager.getDefaultSharedPreferences(this);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//...
Referencing this
before the onCreate caused the "java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference" error for me.
Instantiating the object inside the onCreate() solved my problem, like so:
public class MyFragment extends FragmentActivity {
private SharedPreferences sharedPref;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//...
sharedPref = PreferenceManager.getDefaultSharedPreferences(this);
Hope that helps.
Bonus answer since this use-case brought me here:
In the case where you need to do this as some other user
echo "some output" | sudo -u some_user tee /some/path/some_file
Note that the echo will happen as you and the file write will happen as "some_user" what will NOT work is if you were to run the echo as "some_user" and redirect the output with >> "some_file" because the file redirect will happen as you.
Hint: tee also supports append with the -a flag, if you need to replace a line in a file as another user you could execute sed as the desired user.
Ideally it would return a success/fail response.
We modify a Meouw function to be used with keyup, because when you are using an input it can be more helpful.
Check this:
Hey there!, @heridev and I created a small function in jQuery.
You can try next:
HTML
<input type="text" name="one" class="two-digits"><br>
<input type="text" name="two" class="two-digits">?
jQuery
// apply the two-digits behaviour to elements with 'two-digits' as their class
$( function() {
$('.two-digits').keyup(function(){
if($(this).val().indexOf('.')!=-1){
if($(this).val().split(".")[1].length > 2){
if( isNaN( parseFloat( this.value ) ) ) return;
this.value = parseFloat(this.value).toFixed(2);
}
}
return this; //for chaining
});
});
? DEMO ONLINE:
(@heridev, @vicmaster)
Transition properties are comma delimited in all browsers that support transitions:
.nav a {
transition: color .2s, text-shadow .2s;
}
ease
is the default timing function, so you don't have to specify it. If you really want linear
, you will need to specify it:
transition: color .2s linear, text-shadow .2s linear;
This starts to get repetitive, so if you're going to be using the same times and timing functions across multiple properties it's best to go ahead and use the various transition-*
properties instead of the shorthand:
transition-property: color, text-shadow;
transition-duration: .2s;
transition-timing-function: linear;
Object object = new Object();
// First way
List objects1 = new ArrayList<Object>();
objects1.add(object);
// second way
List<Object> objects2 = Arrays.asList(object);
// Third way
List<Object> objects3 = Collections.singletonList(object);
To encode a parameter in URL I find using .alphanumerics
character set the easiest option:
let encoded = parameter.addingPercentEncoding(withAllowedCharacters: .alphanumerics)
let url = "http://www.example.com/?name=\(encoded!)"
Using any of the standard Character Sets for URL Encoding (like URLQueryAllowedCharacterSet
or URLHostAllowedCharacterSet
) won't work, because they do not exclude =
or &
characters.
Note that by using .alphanumerics
it will encode some characters that do not need to be encoded (like -
, .
, _
or ~
-– see 2.3. Unreserved characters in RFC 3986). I find using .alphanumerics
simpler than constructing a custom character set and do not mind some additional characters to be encoded. If that bothers you, construct a custom character set as is described in How to percent encode a URL String, like for example:
var allowed = CharacterSet.alphanumerics
allowed.insert(charactersIn: "-._~") // as per RFC 3986
let encoded = parameter.addingPercentEncoding(withAllowedCharacters: allowed)
let url = "http://www.example.com/?name=\(encoded!)"
Warning: The encoded
parameter is force unwrapped. For invalid unicode string it might crash. See Why is the return value of String.addingPercentEncoding() optional?. Instead of force unwrapping encoded!
you can use encoded ?? ""
or use if let encoded = ...
.
To use css margin-top
property with purpose to set footer to the bottom of its container. And to use css text-align-last
property to set the footer contents at center.
<div class="container" style="margin-top: 700px; text-align-last: center; ">
<p>My footer Here</p>
</div>
I would recommend Method #2, but you're better off using a metaclass than a base class. Here is a sample implementation:
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class Logger(object):
__metaclass__ = Singleton
Or in Python3
class Logger(metaclass=Singleton):
pass
If you want to run __init__
every time the class is called, add
else:
cls._instances[cls].__init__(*args, **kwargs)
to the if
statement in Singleton.__call__
.
A few words about metaclasses. A metaclass is the class of a class; that is, a class is an instance of its metaclass. You find the metaclass of an object in Python with type(obj)
. Normal new-style classes are of type type
. Logger
in the code above will be of type class 'your_module.Singleton'
, just as the (only) instance of Logger
will be of type class 'your_module.Logger'
. When you call logger with Logger()
, Python first asks the metaclass of Logger
, Singleton
, what to do, allowing instance creation to be pre-empted. This process is the same as Python asking a class what to do by calling __getattr__
when you reference one of it's attributes by doing myclass.attribute
.
A metaclass essentially decides what the definition of a class means and how to implement that definition. See for example http://code.activestate.com/recipes/498149/, which essentially recreates C-style struct
s in Python using metaclasses. The thread What are some (concrete) use-cases for metaclasses? also provides some examples, they generally seem to be related to declarative programming, especially as used in ORMs.
In this situation, if you use your Method #2, and a subclass defines a __new__
method, it will be executed every time you call SubClassOfSingleton()
-- because it is responsible for calling the method that returns the stored instance. With a metaclass, it will only be called once, when the only instance is created. You want to customize what it means to call the class, which is decided by it's type.
In general, it makes sense to use a metaclass to implement a singleton. A singleton is special because is created only once, and a metaclass is the way you customize the creation of a class. Using a metaclass gives you more control in case you need to customize the singleton class definitions in other ways.
Your singletons won't need multiple inheritance (because the metaclass is not a base class), but for subclasses of the created class that use multiple inheritance, you need to make sure the singleton class is the first / leftmost one with a metaclass that redefines __call__
This is very unlikely to be an issue. The instance dict is not in the instance's namespace so it won't accidentally overwrite it.
You will also hear that the singleton pattern violates the "Single Responsibility Principle" -- each class should do only one thing. That way you don't have to worry about messing up one thing the code does if you need to change another, because they are separate and encapsulated. The metaclass implementation passes this test. The metaclass is responsible for enforcing the pattern and the created class and subclasses need not be aware that they are singletons. Method #1 fails this test, as you noted with "MyClass itself is a a function, not a class, so you cannot call class methods from it."
Writing something that works in both Python2 and 3 requires using a slightly more complicated scheme. Since metaclasses are usually subclasses of type type
, it's possible to use one to dynamically create an intermediary base class at run time with it as its metaclass and then use that as the baseclass of the public Singleton
base class. It's harder to explain than to do, as illustrated next:
# works in Python 2 & 3
class _Singleton(type):
""" A metaclass that creates a Singleton base class when called. """
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(_Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class Singleton(_Singleton('SingletonMeta', (object,), {})): pass
class Logger(Singleton):
pass
An ironic aspect of this approach is that it's using subclassing to implement a metaclass. One possible advantage is that, unlike with a pure metaclass, isinstance(inst, Singleton)
will return True
.
On another topic, you've probably already noticed this, but the base class implementation in your original post is wrong. _instances
needs to be referenced on the class, you need to use super()
or you're recursing, and __new__
is actually a static method that you have to pass the class to, not a class method, as the actual class hasn't been created yet when it is called. All of these things will be true for a metaclass implementation as well.
class Singleton(object):
_instances = {}
def __new__(class_, *args, **kwargs):
if class_ not in class_._instances:
class_._instances[class_] = super(Singleton, class_).__new__(class_, *args, **kwargs)
return class_._instances[class_]
class MyClass(Singleton):
pass
c = MyClass()
I originally was writing a comment but it was too long, so I'll add this here. Method #4 is better than the other decorator version, but it's more code than needed for a singleton, and it's not as clear what it does.
The main problems stem from the class being it's own base class. First, isn't it weird to have a class be a subclass of a nearly identical class with the same name that exists only in its __class__
attribute? This also means that you can't define any methods that call the method of the same name on their base class with super()
because they will recurse. This means your class can't customize __new__
, and can't derive from any classes that need __init__
called on them.
Your use case is one of the better examples of wanting to use a singleton. You say in one of the comments "To me logging has always seemed a natural candidate for Singletons." You're absolutely right.
When people say singletons are bad, the most common reason is they are implicit shared state. While with global variables and top-level module imports are explicit shared state, other objects that are passed around are generally instantiated. This is a good point, with two exceptions.
The first, and one that gets mentioned in various places, is when the singletons are constant. Use of global constants, especially enums, is widely accepted, and considered sane because no matter what, none of the users can mess them up for any other user. This is equally true for a constant singleton.
The second exception, which get mentioned less, is the opposite -- when the singleton is only a data sink, not a data source (directly or indirectly). This is why loggers feel like a "natural" use for singletons. As the various users are not changing the loggers in ways other users will care about, there is not really shared state. This negates the primary argument against the singleton pattern, and makes them a reasonable choice because of their ease of use for the task.
Here is a quote from http://googletesting.blogspot.com/2008/08/root-cause-of-singletons.html:
Now, there is one kind of Singleton which is OK. That is a singleton where all of the reachable objects are immutable. If all objects are immutable than Singleton has no global state, as everything is constant. But it is so easy to turn this kind of singleton into mutable one, it is very slippery slope. Therefore, I am against these Singletons too, not because they are bad, but because it is very easy for them to go bad. (As a side note Java enumeration are just these kind of singletons. As long as you don't put state into your enumeration you are OK, so please don't.)
The other kind of Singletons, which are semi-acceptable are those which don't effect the execution of your code, They have no "side effects". Logging is perfect example. It is loaded with Singletons and global state. It is acceptable (as in it will not hurt you) because your application does not behave any different whether or not a given logger is enabled. The information here flows one way: From your application into the logger. Even thought loggers are global state since no information flows from loggers into your application, loggers are acceptable. You should still inject your logger if you want your test to assert that something is getting logged, but in general Loggers are not harmful despite being full of state.
A very effective way to virtually eliminate spam is to have a text field that has text in it such as "Remove this text in order to submit the form!" and that text must be removed in order to submit the form.
Upon form validation, if the text field contains the original text, or any random text for that matter, do not submit the form. Bots can read form names and automatically fill in Name and Email fields but do not know if they have to actually remove text from a certain field in order to submit.
I implemented this method on our corporate website and it totally eliminated the spam we were getting on a daily basis. It really works!
Note that Mongo essentially stores JSON. If your app is dealing with a lot of JS Objects (with nesting) and you want to persist these objects then there is a very strong argument for using Mongo. It makes your DAL and MVC layers ultra thin, because they are not un-packaging all the JS object properties and trying to force-fit them into a structure (schema) that they don't naturally fit into.
We have a system that has several complex JS Objects at its heart, and we love Mongo because we can persist everything really, really easily. Our objects are also rather amorphous and unstructured, and Mongo soaks up that complication without blinking. We have a custom reporting layer that deciphers the amorphous data for human consumption, and that wasn't that difficult to develop.
Look into using the ToString()
method with a specified format.
You may do as follows to Populate treeView with parent and child node. And also with display and value member of parent and child nodes:
arrayRoot = taskData.GetRocordForRoot(); // iterate through database table
for (int j = 0; j <arrayRoot.length; j++) {
TreeNode root = new TreeNode(); // Creating new root node
root.Text = "displayString";
root.Tag = "valueString";
treeView1.Nodes.Add(root); //Adding the root node
arrayChild = taskData.GetRocordForChild();// iterate through database table
for (int i = 0; i < arrayChild.length; i++) {
TreeNode child = new TreeNode(); // creating child node
child.Text = "displayString"
child.Tag = "valueString";
root.Nodes.Add(child); // adding child node
}
}
Try http://www.sql-server-helper.com/tips/date-formats.aspx. Lists all formats needed. In this case select Convert(varchar(10),CONVERT(date,YourDateColumn,106),103) change 103 to 104 id you need dd.mm.yyyy
Your script is right. But by default is of None type. So it considers true of any other value other than None is assigned to args.argument_name variable.
I would suggest you to add a action="store_true". This would make the True/False type of flag. If used its True else False.
import argparse
parser = argparse.ArgumentParser('parser-name')
parser.add_argument("-f","--flag",action="store_true",help="just a flag argument")
usage
$ python3 script.py -f
After parsing when checked with args.f it returns true,
args = parser.parse_args()
print(args.f)
>>>true
I had this issue but for Mac Os, I set the JAVA_HOME variable in the .bash_profile to be export JAVA_HOME=$(/usr/libexec/java_home)
then save. After that ran source ~/.bash_profile
finally mvn -version
and it fixed the issue. Hope that helps
Call it like this:
foo(*ob);
Note that there is no casting going on here, as suggested in your question title. All we have done is de-referenced the pointer to the object which we then pass to the function.
delete[] monsters
is definitely wrong. My heap debugger shows the following output:
allocated non-array memory at 0x3e38f0 (20 bytes)
allocated non-array memory at 0x3e3920 (20 bytes)
allocated non-array memory at 0x3e3950 (20 bytes)
allocated non-array memory at 0x3e3980 (20 bytes)
allocated non-array memory at 0x3e39b0 (20 bytes)
allocated non-array memory at 0x3e39e0 (20 bytes)
releasing array memory at 0x22ff38
As you can see, you are trying to release with the wrong form of delete (non-array vs. array), and the pointer 0x22ff38 has never been returned by a call to new. The second version shows the correct output:
[allocations omitted for brevity]
releasing non-array memory at 0x3e38f0
releasing non-array memory at 0x3e3920
releasing non-array memory at 0x3e3950
releasing non-array memory at 0x3e3980
releasing non-array memory at 0x3e39b0
releasing non-array memory at 0x3e39e0
Anyway, I prefer a design where manually implementing the destructor is not necessary to begin with.
#include <array>
#include <memory>
class Foo
{
std::array<std::shared_ptr<Monster>, 6> monsters;
Foo()
{
for (int i = 0; i < 6; ++i)
{
monsters[i].reset(new Monster());
}
}
virtual ~Foo()
{
// nothing to do manually
}
};
Your method looks like this:
public static bool HasProperty(this object obj, string propertyName)
{
return obj.GetType().GetProperty(propertyName) != null;
}
This adds an extension onto object
- the base class of everything. When you call this extension you're passing it a Type
:
var res = typeof(MyClass).HasProperty("Label");
Your method expects an instance of a class, not a Type
. Otherwise you're essentially doing
typeof(MyClass) - this gives an instanceof `System.Type`.
Then
type.GetType() - this gives `System.Type`
Getproperty('xxx') - whatever you provide as xxx is unlikely to be on `System.Type`
As @PeterRitchie correctly points out, at this point your code is looking for property Label
on System.Type
. That property does not exist.
The solution is either
a) Provide an instance of MyClass to the extension:
var myInstance = new MyClass()
myInstance.HasProperty("Label")
b) Put the extension on System.Type
public static bool HasProperty(this Type obj, string propertyName)
{
return obj.GetProperty(propertyName) != null;
}
and
typeof(MyClass).HasProperty("Label");
You need to precede the lines starting with gcc
and rm
with a hard tab. Commands in make rules are required to start with a tab (unless they follow a semicolon on the same line).
The result should look like this:
PROG = semsearch
all: $(PROG)
%: %.c
gcc -o $@ $< -lpthread
clean:
rm $(PROG)
Note that some editors may be configured to insert a sequence of spaces instead of a hard tab. If there are spaces at the start of these lines you'll also see the "missing separator" error. If you do have problems inserting hard tabs, use the semicolon way:
PROG = semsearch
all: $(PROG)
%: %.c ; gcc -o $@ $< -lpthread
clean: ; rm $(PROG)
If your problem is so special that you really need to have more readers open simultaneously, and your requirements allow not older than SQL Server 2005 DB backend, then the magic word is MARS (Multiple Active Result Sets). http://msdn.microsoft.com/en-us/library/ms345109%28v=SQL.90%29.aspx. Bob Vale's linked topic's solution shows how to enable it: specify MultipleActiveResultSets=true
in your connection string. I just tell this as an interesting possibility, but you should rather transform your solution.
As Shubham Jain stated, this is working to me: driver.findElement(By.id("invoice_supplier_id")).sendKeys("value"??, "new value");
Use the ArrayList copy constructor, then sort that.
List oldList;
List newList = new ArrayList(oldList);
Collections.sort(newList);
After making the copy, any changes to newList do not affect oldList.
Note however that only the references are copied, so the two lists share the same objects, so changes made to elements of one list affect the elements of the other.
There are some Microsoft Themes in the WPF page on CodePlex:
I wanted a more exact and useful answer to this question. Here's the real answer (adjust accordingly if you want a byte array specifically; obviously the math will be off by a factor of 8 bits : 1 byte
):
class BitArray {
constructor(bits = 0) {
this.uints = new Uint32Array(~~(bits / 32));
}
getBit(bit) {
return (this.uints[~~(bit / 32)] & (1 << (bit % 32))) != 0 ? 1 : 0;
}
assignBit(bit, value) {
if (value) {
this.uints[~~(bit / 32)] |= (1 << (bit % 32));
} else {
this.uints[~~(bit / 32)] &= ~(1 << (bit % 32));
}
}
get size() {
return this.uints.length * 32;
}
static bitsToUints(bits) {
return ~~(bits / 32);
}
}
Usage:
let bits = new BitArray(500);
for (let uint = 0; uint < bits.uints.length; ++uint) {
bits.uints[uint] = 457345834;
}
for (let bit = 0; bit < 50; ++bit) {
bits.assignBit(bit, 1);
}
str = '';
for (let bit = bits.size - 1; bit >= 0; --bit) {
str += bits.getBit(bit);
}
str;
Output:
"00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000101000101100101010
00011011010000111111111111111111
11111111111111111111111111111111"
Note: This class is really slow to e.g. assign bits (i.e. ~2s per 10 million assignments) if it's created as a global variable, at least in the Firefox 76.0 Console on Linux... If, on the other hand, it's created as a variable (i.e. let bits = new BitArray(1e7);
), then it's blazingly fast (i.e. ~300ms per 10 million assignments)!
For more info, see here:
Note that I used Uint32Array because there's no way to directly have a bit/byte array (that you can interact with directly) and because even though there's a BigUint64Array
, JS only supports 32 bits:
Bitwise operators treat their operands as a sequence of 32 bits
...
The operands of all bitwise operators are converted to...32-bit integers
New, improved answer to an old, frequently asked question...
Double quote ("
) may appear without escaping:
In XML textual content:
<NoEscapeNeeded>He said, "Don't quote me."</NoEscapeNeeded>
In XML attributes delimited by single quotes ('
):
<NoEscapeNeeded name='Pete "Maverick" Mitchell'/>
Note: switching to single quotes ('
) also requires no escaping:
<NoEscapeNeeded name="Pete 'Maverick' Mitchell"/>
Double quote ("
) must be escaped:
In XML attributes delimited by double quotes:
<EscapeNeeded name="Pete "Maverick" Mitchell"/>
Double quote ("
) must be escaped as "
in XML only in very limited contexts.
you can use simply inside your controller:
return response()->download($filePath);
Happy coding :)
I'm not sure if I'm answering the question right, but here's a familiar example:
The return type of GetLastError()
in Windows is nonzero if there was an error, or zero otherwise. The reverse is usually true of the return value of the function you called.
Chart.JS API has changed since this was posted and older examples did not seem to be working for me. here is an updated fiddle that works on the newer versions
HTML:
<body>
<canvas id="canvas" height="450" width="600"></canvas>
<img id="url" />
</body>
JS:
function done(){
alert("haha");
var url=myLine.toBase64Image();
document.getElementById("url").src=url;
}
var options = {
bezierCurve : false,
animation: {
onComplete: done
}
};
var myLine = new
Chart(document.getElementById("canvas").getContext("2d"),
{
data:lineChartData,
type:"line",
options:options
}
);
I ran into this problem yesterday, so I created a React-friendly solution.
Check out react-native-listener. It's working very well so far. Feedback appreciated.
Run apt-get install build-essential
on your system.
This package depends on other packages considered to be essential for builds and will install them. If you find you have to build packages, this can be helpful to avoid piecemeal resolution of dependencies.
See this page for more info.
I found myself requiring this functionality often enough that I packaged it into a library called std-pour. It should let you execute a command and view the output in real time. To install simply:
npm install std-pour
Then it's simple enough to execute a command and see the output in realtime:
const { pour } = require('std-pour');
pour('ping', ['8.8.8.8', '-c', '4']).then(code => console.log(`Error Code: ${code}`));
It's promised based so you can chain multiple commands. It's even function signature-compatible with child_process.spawn
so it should be a drop in replacement anywhere you're using it.
In case anyone's arriving here looking for a solution applicable to RMarkdown, this will suppress all output:
```{r error=FALSE, warning=FALSE, message=FALSE}
invisible({capture.output({
# Your code goes here
2 * 2
# etc
# etc
})})
```
The code will run, but the output will not be printed to the HTML document
The answers so far only consider the worth of have a null
key, but the question also asks about any number of null values
.
The benefit of storing the value null
against a key in a HashMap is the same as in databases, etc - you can record a distinction between having a value that is empty (e.g. string ""), and not having a value at all (null).
If you wish to use GIT CLI and not interact with the build in GIT wrappers in Visual Studio you need to enable Alternate Authentication Credentials
Open your account (VS Online account)
-> click on your name on the top right
-> My Profile
-> Credentials.
and set it up.
This is a modified version of Alex's answer. We can save the state of a module's namespace and restore it by using the following 2 methods...
__saved_context__ = {}
def saveContext():
import sys
__saved_context__.update(sys.modules[__name__].__dict__)
def restoreContext():
import sys
names = sys.modules[__name__].__dict__.keys()
for n in names:
if n not in __saved_context__:
del sys.modules[__name__].__dict__[n]
saveContext()
hello = 'hi there'
print hello # prints "hi there" on stdout
restoreContext()
print hello # throws an exception
You can also add a line "clear = restoreContext" before calling saveContext() and clear() will work like matlab's clear.
$('.close').click(function() {
//Code to be executed when close is clicked
$('#result').html('yes,result');
});
-- If no parameters need to be passed to a procedure, simply:
BEGIN
MY_PACKAGE_NAME.MY_PROCEDURE_NAME
END;
Pure JavaScript solution:
function scrollToTop() {
window.scrollTo({
top: 0,
behavior: 'smooth'
});
I write an animated solution on Codepen
Also, you can try another solution with CSS scroll-behavior: smooth
property.
html {
scroll-behavior: smooth;
}
@media (prefers-reduced-motion: reduce) {
html {
scroll-behavior: auto;
}
}
You will find multiple different methods that people use and they each have there own place.
<?php if($first_condition): ?>
/*$first_condition is true*/
<?php elseif ($second_condition): ?>
/*$first_condition is false and $second_condition is true*/
<?php else: ?>
/*$first_condition and $second_condition are false*/
<?php endif; ?>
If in your php.ini attribute short_open_tag = true
(this is normally found on line 141
of the default php.ini file) you can replace your php open tag from <?php
to <?
. This is not advised as most live server environments have this turned off (including many CMS's like Drupal, WordPress and Joomla). I have already tested short hand open tags in Drupal and confirmed that it will break your site, so stick with <?php
. short_open_tag
is not on by default in all server configurations and must not be assumed as such when developing for unknown server configurations. Many hosting companies have short_open_tag
turned off.
A quick search of short_open_tag
in stackExchange shows 830 results. https://stackoverflow.com/search?q=short_open_tag
That's a lot of people having problems with something they should just not play with.
with some server environments and applications, short hand php open tags will still crash your code even with short_open_tag
set to true
.
short_open_tag
will be removed in PHP6 so don't use short hand tags.
all future PHP versions will be dropping short_open_tag
"It's been recommended for several years that you not use the short tag "short cut" and instead to use the full tag combination. With the wide spread use of XML and use of these tags by other languages, the server can become easily confused and end up parsing the wrong code in the wrong context. But because this short cut has been a feature for such a long time, it's currently still supported for backwards compatibility, but we recommend you don't use them." – Jelmer Sep 25 '12 at 9:00 php: "short_open_tag = On" not working
and
Normally you write PHP like so: . However if allow_short_tags directive is enabled you're able to use: . Also sort tags provides extra syntax: which is equal to .
Short tags might seem cool but they're not. They causes only more problems. Oh... and IIRC they'll be removed from PHP6. Crozin answered Aug 24 '10 at 22:12 php short_open_tag problem
and
To answer the why part, I'd quote Zend PHP 5 certification guide: "Short tags were, for a time, the standard in the PHP world; however, they do have the major drawback of conflicting with XML headers and, therefore, have somewhat fallen by the wayside." – Fluffy Apr 13 '11 at 14:40 Are PHP short tags acceptable to use?
You may also see people use the following example:
<?php if($first_condition){ ?>
/*$first_condition is true*/
<?php }else if ($second_condition){ ?>
/*$first_condition is false and $second_condition is true*/
<?php }else{ ?>
/*$first_condition and $second_condition are false*/
<?php } ?>
This will work but it is highly frowned upon as it's not considered as legible and is not what you would use this format for. If you had a PHP file where you had a block of PHP code that didn't have embedded tags inside, then you would use the bracket format.
The following example shows when to use the bracket method
<?php
if($first_condition){
/*$first_condition is true*/
}else if ($second_condition){
/*$first_condition is false and $second_condition is true*/
}else{
/*$first_condition and $second_condition are false*/
}
?>
If you're doing this code for yourself you can do what you like, but if your working with a team at a job it is advised to use the correct format for the correct circumstance. If you use brackets in embedded html/php scripts that is a good way to get fired, as no one will want to clean up your code after you. IT bosses will care about code legibility and college professors grade on legibility.
UPDATE
based on comments from duskwuff its still unclear if shorthand is discouraged (by the php standards) or not. I'll update this answer as I get more information. But based on many documents found on the web about shorthand being bad for portability. I would still personally not use it as it gives no advantage and you must rely on a setting being on that is not on for every web host.
use HASHBYTES
declare @first_value nvarchar(1) = 'a'
declare @second_value navarchar(1) = 'A'
if HASHBYTES('SHA1',@first_value) = HASHBYTES('SHA1',@second_value) begin
print 'equal'
end else begin
print 'not equal'
end
-- output:
-- not equal
...in where clause
declare @example table (ValueA nvarchar(1), ValueB nvarchar(1))
insert into @example (ValueA, ValueB)
values ('a', 'A'),
('a', 'a'),
('a', 'b')
select ValueA + ' = ' + ValueB
from @example
where hashbytes('SHA1', ValueA) = hashbytes('SHA1', ValueB)
-- output:
-- a = a
select ValueA + ' <> ' + ValueB
from @example
where hashbytes('SHA1', ValueA) <> hashbytes('SHA1', ValueB)
-- output:
-- a <> A
-- a <> b
or to find a value
declare @value_b nvarchar(1) = 'A'
select ValueB + ' = ' + @value_b
from @example
where hashbytes('SHA1', ValueB) = hasbytes('SHA1', @value_b)
-- output:
-- A = A
As requested by dube I'm posting my modified version of Siarhei Kuchuk's answer.
If you want to check my changes search for // EDT
. I've commented most of it.
The Setup
class GlobalKeyboardHookEventArgs : HandledEventArgs
{
public GlobalKeyboardHook.KeyboardState KeyboardState { get; private set; }
public GlobalKeyboardHook.LowLevelKeyboardInputEvent KeyboardData { get; private set; }
public GlobalKeyboardHookEventArgs(
GlobalKeyboardHook.LowLevelKeyboardInputEvent keyboardData,
GlobalKeyboardHook.KeyboardState keyboardState)
{
KeyboardData = keyboardData;
KeyboardState = keyboardState;
}
}
//Based on https://gist.github.com/Stasonix
class GlobalKeyboardHook : IDisposable
{
public event EventHandler<GlobalKeyboardHookEventArgs> KeyboardPressed;
// EDT: Added an optional parameter (registeredKeys) that accepts keys to restict
// the logging mechanism.
/// <summary>
///
/// </summary>
/// <param name="registeredKeys">Keys that should trigger logging. Pass null for full logging.</param>
public GlobalKeyboardHook(Keys[] registeredKeys = null)
{
RegisteredKeys = registeredKeys;
_windowsHookHandle = IntPtr.Zero;
_user32LibraryHandle = IntPtr.Zero;
_hookProc = LowLevelKeyboardProc; // we must keep alive _hookProc, because GC is not aware about SetWindowsHookEx behaviour.
_user32LibraryHandle = LoadLibrary("User32");
if (_user32LibraryHandle == IntPtr.Zero)
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode, $"Failed to load library 'User32.dll'. Error {errorCode}: {new Win32Exception(Marshal.GetLastWin32Error()).Message}.");
}
_windowsHookHandle = SetWindowsHookEx(WH_KEYBOARD_LL, _hookProc, _user32LibraryHandle, 0);
if (_windowsHookHandle == IntPtr.Zero)
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode, $"Failed to adjust keyboard hooks for '{Process.GetCurrentProcess().ProcessName}'. Error {errorCode}: {new Win32Exception(Marshal.GetLastWin32Error()).Message}.");
}
}
protected virtual void Dispose(bool disposing)
{
if (disposing)
{
// because we can unhook only in the same thread, not in garbage collector thread
if (_windowsHookHandle != IntPtr.Zero)
{
if (!UnhookWindowsHookEx(_windowsHookHandle))
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode, $"Failed to remove keyboard hooks for '{Process.GetCurrentProcess().ProcessName}'. Error {errorCode}: {new Win32Exception(Marshal.GetLastWin32Error()).Message}.");
}
_windowsHookHandle = IntPtr.Zero;
// ReSharper disable once DelegateSubtraction
_hookProc -= LowLevelKeyboardProc;
}
}
if (_user32LibraryHandle != IntPtr.Zero)
{
if (!FreeLibrary(_user32LibraryHandle)) // reduces reference to library by 1.
{
int errorCode = Marshal.GetLastWin32Error();
throw new Win32Exception(errorCode, $"Failed to unload library 'User32.dll'. Error {errorCode}: {new Win32Exception(Marshal.GetLastWin32Error()).Message}.");
}
_user32LibraryHandle = IntPtr.Zero;
}
}
~GlobalKeyboardHook()
{
Dispose(false);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
private IntPtr _windowsHookHandle;
private IntPtr _user32LibraryHandle;
private HookProc _hookProc;
delegate IntPtr HookProc(int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll")]
private static extern IntPtr LoadLibrary(string lpFileName);
[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
private static extern bool FreeLibrary(IntPtr hModule);
/// <summary>
/// The SetWindowsHookEx function installs an application-defined hook procedure into a hook chain.
/// You would install a hook procedure to monitor the system for certain types of events. These events are
/// associated either with a specific thread or with all threads in the same desktop as the calling thread.
/// </summary>
/// <param name="idHook">hook type</param>
/// <param name="lpfn">hook procedure</param>
/// <param name="hMod">handle to application instance</param>
/// <param name="dwThreadId">thread identifier</param>
/// <returns>If the function succeeds, the return value is the handle to the hook procedure.</returns>
[DllImport("USER32", SetLastError = true)]
static extern IntPtr SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hMod, int dwThreadId);
/// <summary>
/// The UnhookWindowsHookEx function removes a hook procedure installed in a hook chain by the SetWindowsHookEx function.
/// </summary>
/// <param name="hhk">handle to hook procedure</param>
/// <returns>If the function succeeds, the return value is true.</returns>
[DllImport("USER32", SetLastError = true)]
public static extern bool UnhookWindowsHookEx(IntPtr hHook);
/// <summary>
/// The CallNextHookEx function passes the hook information to the next hook procedure in the current hook chain.
/// A hook procedure can call this function either before or after processing the hook information.
/// </summary>
/// <param name="hHook">handle to current hook</param>
/// <param name="code">hook code passed to hook procedure</param>
/// <param name="wParam">value passed to hook procedure</param>
/// <param name="lParam">value passed to hook procedure</param>
/// <returns>If the function succeeds, the return value is true.</returns>
[DllImport("USER32", SetLastError = true)]
static extern IntPtr CallNextHookEx(IntPtr hHook, int code, IntPtr wParam, IntPtr lParam);
[StructLayout(LayoutKind.Sequential)]
public struct LowLevelKeyboardInputEvent
{
/// <summary>
/// A virtual-key code. The code must be a value in the range 1 to 254.
/// </summary>
public int VirtualCode;
// EDT: added a conversion from VirtualCode to Keys.
/// <summary>
/// The VirtualCode converted to typeof(Keys) for higher usability.
/// </summary>
public Keys Key { get { return (Keys)VirtualCode; } }
/// <summary>
/// A hardware scan code for the key.
/// </summary>
public int HardwareScanCode;
/// <summary>
/// The extended-key flag, event-injected Flags, context code, and transition-state flag. This member is specified as follows. An application can use the following values to test the keystroke Flags. Testing LLKHF_INJECTED (bit 4) will tell you whether the event was injected. If it was, then testing LLKHF_LOWER_IL_INJECTED (bit 1) will tell you whether or not the event was injected from a process running at lower integrity level.
/// </summary>
public int Flags;
/// <summary>
/// The time stamp stamp for this message, equivalent to what GetMessageTime would return for this message.
/// </summary>
public int TimeStamp;
/// <summary>
/// Additional information associated with the message.
/// </summary>
public IntPtr AdditionalInformation;
}
public const int WH_KEYBOARD_LL = 13;
//const int HC_ACTION = 0;
public enum KeyboardState
{
KeyDown = 0x0100,
KeyUp = 0x0101,
SysKeyDown = 0x0104,
SysKeyUp = 0x0105
}
// EDT: Replaced VkSnapshot(int) with RegisteredKeys(Keys[])
public static Keys[] RegisteredKeys;
const int KfAltdown = 0x2000;
public const int LlkhfAltdown = (KfAltdown >> 8);
public IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam)
{
bool fEatKeyStroke = false;
var wparamTyped = wParam.ToInt32();
if (Enum.IsDefined(typeof(KeyboardState), wparamTyped))
{
object o = Marshal.PtrToStructure(lParam, typeof(LowLevelKeyboardInputEvent));
LowLevelKeyboardInputEvent p = (LowLevelKeyboardInputEvent)o;
var eventArguments = new GlobalKeyboardHookEventArgs(p, (KeyboardState)wparamTyped);
// EDT: Removed the comparison-logic from the usage-area so the user does not need to mess around with it.
// Either the incoming key has to be part of RegisteredKeys (see constructor on top) or RegisterdKeys
// has to be null for the event to get fired.
var key = (Keys)p.VirtualCode;
if (RegisteredKeys == null || RegisteredKeys.Contains(key))
{
EventHandler<GlobalKeyboardHookEventArgs> handler = KeyboardPressed;
handler?.Invoke(this, eventArguments);
fEatKeyStroke = eventArguments.Handled;
}
}
return fEatKeyStroke ? (IntPtr)1 : CallNextHookEx(IntPtr.Zero, nCode, wParam, lParam);
}
}
The Usage differences can be seen here
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private GlobalKeyboardHook _globalKeyboardHook;
private void buttonHook_Click(object sender, EventArgs e)
{
// Hooks only into specified Keys (here "A" and "B").
_globalKeyboardHook = new GlobalKeyboardHook(new Keys[] { Keys.A, Keys.B });
// Hooks into all keys.
_globalKeyboardHook = new GlobalKeyboardHook();
_globalKeyboardHook.KeyboardPressed += OnKeyPressed;
}
private void OnKeyPressed(object sender, GlobalKeyboardHookEventArgs e)
{
// EDT: No need to filter for VkSnapshot anymore. This now gets handled
// through the constructor of GlobalKeyboardHook(...).
if (e.KeyboardState == GlobalKeyboardHook.KeyboardState.KeyDown)
{
// Now you can access both, the key and virtual code
Keys loggedKey = e.KeyboardData.Key;
int loggedVkCode = e.KeyboardData.VirtualCode;
}
}
}
Thanks to Siarhei Kuchuk for his post. Even tho I've simplified the usage this initial code was very useful for me.
Anyone interested in doing this should read the documentation of the Django Sessions framework. It stores a session ID in the user's cookies, but maps all the cookies-like data to your database. This is an improvement on the typical cookies-based workflow for HTTP requests.
Here is an example with a Django view ...
def homepage(request):
request.session.setdefault('how_many_visits', 0)
request.session['how_many_visits'] += 1
print(request.session['how_many_visits'])
return render(request, 'home.html', {})
If you keep visiting the page over and over, you'll see the value start incrementing up from 1 until you clear your cookies, visit on a new browser, go incognito, or do anything else that sidesteps Django's Session ID cookie.
So the first part of the answer is how to do what the subject asks as this was how I initially interpreted it and a few people seemed to find helpful. The question was since clarified and I've extended the answer to address that.
Setting a timer
First you need to create a Timer (I'm using the java.util
version here):
import java.util.Timer;
..
Timer timer = new Timer();
To run the task once you would do:
timer.schedule(new TimerTask() {
@Override
public void run() {
// Your database code here
}
}, 2*60*1000);
// Since Java-8
timer.schedule(() -> /* your database code here */, 2*60*1000);
To have the task repeat after the duration you would do:
timer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
// Your database code here
}
}, 2*60*1000, 2*60*1000);
// Since Java-8
timer.scheduleAtFixedRate(() -> /* your database code here */, 2*60*1000, 2*60*1000);
Making a task timeout
To specifically do what the clarified question asks, that is attempting to perform a task for a given period of time, you could do the following:
ExecutorService service = Executors.newSingleThreadExecutor();
try {
Runnable r = new Runnable() {
@Override
public void run() {
// Database task
}
};
Future<?> f = service.submit(r);
f.get(2, TimeUnit.MINUTES); // attempt the task for two minutes
}
catch (final InterruptedException e) {
// The thread was interrupted during sleep, wait or join
}
catch (final TimeoutException e) {
// Took too long!
}
catch (final ExecutionException e) {
// An exception from within the Runnable task
}
finally {
service.shutdown();
}
This will execute normally with exceptions if the task completes within 2 minutes. If it runs longer than that, the TimeoutException will be throw.
One issue is that although you'll get a TimeoutException after the two minutes, the task will actually continue to run, although presumably a database or network connection will eventually time out and throw an exception in the thread. But be aware it could consume resources until that happens.
public bool MojTestPalindrome (string word)
{
bool yes = false;
char[]test1 = word.ToArray();
char[] test2 = test1.Reverse().ToArray();
for (int i=0; i< test2.Length; i++)
{
if (test1[i] != test2[test2.Length - 1 - i])
{
yes = false;
break;
}
else {
yes = true;
}
}
if (yes == true)
{
return true;
}
else
return false;
}
Original from Sept. 13, 2015:
Quick and easy.
$.each(yourArray, function(index, value){
$('.element').html( $('.element').html() + '<span>' + value +'</span>')
});
Update Sept 9, 2019: No jQuery is needed to iterate the array.
yourArray.forEach((value) => {
$(".element").html(`${$(".element").html()}<span>${value}</span>`);
});
/* --- Or without jQuery at all --- */
yourArray.forEach((value) => {
document.querySelector(".element").innerHTML += `<span>${value}</span>`;
});
git pull = git fetch + git merge
Try this:
ORDER BY 1, 2
OR
ORDER BY rsc.RadioServiceCodeId, rsc.RadioServiceCode + ' - ' + rsc.RadioService
Most of the answers are too lengthy or too short not fulfilling the purpose. For those how are looking for Java or Kotlin code to Convert bitmap to File Object. Here is the detailed article I have written on the topic. Convert Bitmap to File in Android
public static File bitmapToFile(Context context,Bitmap bitmap, String fileNameToSave) { // File name like "image.png"
//create a file to write bitmap data
File file = null;
try {
file = new File(Environment.getExternalStorageDirectory() + File.separator + fileNameToSave);
file.createNewFile();
//Convert bitmap to byte array
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 0 , bos); // YOU can also save it in JPEG
byte[] bitmapdata = bos.toByteArray();
//write the bytes in file
FileOutputStream fos = new FileOutputStream(file);
fos.write(bitmapdata);
fos.flush();
fos.close();
return file;
}catch (Exception e){
e.printStackTrace();
return file; // it will return null
}
}
You can use hasOwnProperty
method to check this
> localStorage.setItem('foo', 123)
undefined
> localStorage.hasOwnProperty('foo')
true
> localStorage.hasOwnProperty('bar')
false
Works in current versions of Chrome(Mac), Firefox(Mac) and Safari.
Use the CREATE TABLE SELECT syntax.
http://dev.mysql.com/doc/refman/5.0/en/create-table-select.html
CREATE TABLE new_tbl SELECT * FROM orig_tbl;
For a fully transparent background use:
background: transparent;
Otherwise for a semi-transparent color fill use:
background: rgba(255,255,255,0.5); // or hsla(0, 0%, 100%, 0.5)
where the values are:
background: rgba(red,green,blue,opacity); // or hsla(hue, saturation, lightness, opacity)
You can also use rgba values for gradient backgrounds.
To get transparency on an image background simply reduce the opacity of the image in an image editor of you choice beforehand.
echo $a | grep -bo cat | sed 's/:.*$//'
Not sure about flexbox but you can do using the position property.
set parent div
position: relative
and child element which might be an <p>
or <h1>
etc.. set position: absolute
and bottom: 0
.
Example:
index.html
<div class="parent">
<p>Child</p>
</div>
style.css
.parent {
background: gray;
width: 10%;
height: 100px;
position: relative;
}
p {
position: absolute;
bottom: 0;
}
I learned how to do these sort of things reading "PRO HTML and CSS Design Patterns". The display:block
is the default display value for the div
, but I like to make it explicit. The container has to be the right type; position
attribute is fixed
, relative
, or absolute
.
.stretchedToMargin {_x000D_
display: block;_x000D_
position:absolute;_x000D_
height:auto;_x000D_
bottom:0;_x000D_
top:0;_x000D_
left:0;_x000D_
right:0;_x000D_
margin-top:20px;_x000D_
margin-bottom:20px;_x000D_
margin-right:80px;_x000D_
margin-left:80px;_x000D_
background-color: green;_x000D_
}
_x000D_
<div class="stretchedToMargin">_x000D_
Hello, world_x000D_
</div>
_x000D_
Use Where-Object
and test the $_.CreationTime
:
Get-ChildItem 'PATH' -recurse -include @("*.tif*","*.jp2","*.pdf") |
Where-Object { $_.CreationTime -ge "03/01/2013" -and $_.CreationTime -le "03/31/2013" }
svn:// doesn't talk http, therefor there's nothing a http proxy could do.
Any reason why http doesn't work? Have you considered https? If you really need it, you probably have to have port 3690 opened in your firewall.
There is no such functionality in jQuery. Use JSON.stringify
or alternatively any jQuery plugin with similar functionality (e.g jquery-json).
Created a npm package for this https://www.npmjs.com/package/array.chunk
var result = [];
for (var i = 0; i < arr.length; i += size) {
result.push(arr.slice(i, size + i));
}
return result;
When using a TypedArray
var result = [];
for (var i = 0; i < arr.length; i += size) {
result.push(arr.subarray(i, size + i));
}
return result;
You can call:
arr.slice(Math.max(arr.length - 5, 1))
If you don't want to exclude the first element, use
arr.slice(Math.max(arr.length - 5, 0))
Initially my repo said "Already up to date."
MINGW64 (feature/Issue_123)
$ git merge develop
Output:
Already up to date.
But the code is not up to date & it is showing some differences in some files.
MINGW64 (feature/Issue_123)
$ git diff develop
Output:
diff --git
a/src/main/database/sql/additional/pkg_etl.sql
b/src/main/database/sql/additional/pkg_etl.sql
index ba2a257..1c219bb 100644
--- a/src/main/database/sql/additional/pkg_etl.sql
+++ b/src/main/database/sql/additional/pkg_etl.sql
However, merging fixes it.
MINGW64 (feature/Issue_123)
$ git merge origin/develop
Output:
Updating c7c0ac9..09959e3
Fast-forward
3 files changed, 157 insertions(+), 92 deletions(-)
Again I have confirmed this by using diff
command.
MINGW64 (feature/Issue_123)
$ git diff develop
No differences in the code now!
btoa() only support characters from String.fromCodePoint(0) up to String.fromCodePoint(255). For Base64 characters with a code point 256 or higher you need to encode/decode these before and after.
And in this point it becomes tricky...
Every possible sign are arranged in a Unicode-Table. The Unicode-Table is divided in different planes (languages, math symbols, and so on...). Every sign in a plane has a unique code point number. Theoretically, the number can become arbitrarily large.
A computer stores the data in bytes (8 bit, hexadecimal 0x00 - 0xff, binary 00000000 - 11111111, decimal 0 - 255). This range normally use to save basic characters (Latin1 range).
For characters with higher codepoint then 255 exist different encodings. JavaScript use 16 bits per sign (UTF-16), the string called DOMString. Unicode can handle code points up to 0x10fffff. That means, that a method must be exist to store several bits over several cells away.
String.fromCodePoint(0x10000).length == 2
UTF-16 use surrogate pairs to store 20bits in two 16bit cells. The first higher surrogate begins with 110110xxxxxxxxxx, the lower second one with 110111xxxxxxxxxx. Unicode reserved own planes for this: https://unicode-table.com/de/#high-surrogates
To store characters in bytes (Latin1 range) standardized procedures use UTF-8.
Sorry to say that, but I think there is no other way to implement this function self.
function stringToUTF8(str)
{
let bytes = [];
for(let character of str)
{
let code = character.codePointAt(0);
if(code <= 127)
{
let byte1 = code;
bytes.push(byte1);
}
else if(code <= 2047)
{
let byte1 = 0xC0 | (code >> 6);
let byte2 = 0x80 | (code & 0x3F);
bytes.push(byte1, byte2);
}
else if(code <= 65535)
{
let byte1 = 0xE0 | (code >> 12);
let byte2 = 0x80 | ((code >> 6) & 0x3F);
let byte3 = 0x80 | (code & 0x3F);
bytes.push(byte1, byte2, byte3);
}
else if(code <= 2097151)
{
let byte1 = 0xF0 | (code >> 18);
let byte2 = 0x80 | ((code >> 12) & 0x3F);
let byte3 = 0x80 | ((code >> 6) & 0x3F);
let byte4 = 0x80 | (code & 0x3F);
bytes.push(byte1, byte2, byte3, byte4);
}
}
return bytes;
}
function utf8ToString(bytes, fallback)
{
let valid = undefined;
let codePoint = undefined;
let codeBlocks = [0, 0, 0, 0];
let result = "";
for(let offset = 0; offset < bytes.length; offset++)
{
let byte = bytes[offset];
if((byte & 0x80) == 0x00)
{
codeBlocks[0] = byte & 0x7F;
codePoint = codeBlocks[0];
}
else if((byte & 0xE0) == 0xC0)
{
codeBlocks[0] = byte & 0x1F;
byte = bytes[++offset];
if(offset >= bytes.length || (byte & 0xC0) != 0x80) { valid = false; break; }
codeBlocks[1] = byte & 0x3F;
codePoint = (codeBlocks[0] << 6) + codeBlocks[1];
}
else if((byte & 0xF0) == 0xE0)
{
codeBlocks[0] = byte & 0xF;
for(let blockIndex = 1; blockIndex <= 2; blockIndex++)
{
byte = bytes[++offset];
if(offset >= bytes.length || (byte & 0xC0) != 0x80) { valid = false; break; }
codeBlocks[blockIndex] = byte & 0x3F;
}
if(valid === false) { break; }
codePoint = (codeBlocks[0] << 12) + (codeBlocks[1] << 6) + codeBlocks[2];
}
else if((byte & 0xF8) == 0xF0)
{
codeBlocks[0] = byte & 0x7;
for(let blockIndex = 1; blockIndex <= 3; blockIndex++)
{
byte = bytes[++offset];
if(offset >= bytes.length || (byte & 0xC0) != 0x80) { valid = false; break; }
codeBlocks[blockIndex] = byte & 0x3F;
}
if(valid === false) { break; }
codePoint = (codeBlocks[0] << 18) + (codeBlocks[1] << 12) + (codeBlocks[2] << 6) + (codeBlocks[3]);
}
else
{
valid = false; break;
}
result += String.fromCodePoint(codePoint);
}
if(valid === false)
{
if(!fallback)
{
throw new TypeError("Malformed utf-8 encoding.");
}
result = "";
for(let offset = 0; offset != bytes.length; offset++)
{
result += String.fromCharCode(bytes[offset] & 0xFF);
}
}
return result;
}
function decodeBase64(text, binary)
{
if(/[^0-9a-zA-Z\+\/\=]/.test(text)) { throw new TypeError("The string to be decoded contains characters outside of the valid base64 range."); }
let codePointA = 'A'.codePointAt(0);
let codePointZ = 'Z'.codePointAt(0);
let codePointa = 'a'.codePointAt(0);
let codePointz = 'z'.codePointAt(0);
let codePointZero = '0'.codePointAt(0);
let codePointNine = '9'.codePointAt(0);
let codePointPlus = '+'.codePointAt(0);
let codePointSlash = '/'.codePointAt(0);
function getCodeFromKey(key)
{
let keyCode = key.codePointAt(0);
if(keyCode >= codePointA && keyCode <= codePointZ)
{
return keyCode - codePointA;
}
else if(keyCode >= codePointa && keyCode <= codePointz)
{
return keyCode + 26 - codePointa;
}
else if(keyCode >= codePointZero && keyCode <= codePointNine)
{
return keyCode + 52 - codePointZero;
}
else if(keyCode == codePointPlus)
{
return 62;
}
else if(keyCode == codePointSlash)
{
return 63;
}
return undefined;
}
let codes = Array.from(text).map(character => getCodeFromKey(character));
let bytesLength = Math.ceil(codes.length / 4) * 3;
if(codes[codes.length - 2] == undefined) { bytesLength = bytesLength - 2; } else if(codes[codes.length - 1] == undefined) { bytesLength--; }
let bytes = new Uint8Array(bytesLength);
for(let offset = 0, index = 0; offset < bytes.length;)
{
let code1 = codes[index++];
let code2 = codes[index++];
let code3 = codes[index++];
let code4 = codes[index++];
let byte1 = (code1 << 2) | (code2 >> 4);
let byte2 = ((code2 & 0xf) << 4) | (code3 >> 2);
let byte3 = ((code3 & 0x3) << 6) | code4;
bytes[offset++] = byte1;
bytes[offset++] = byte2;
bytes[offset++] = byte3;
}
if(binary) { return bytes; }
return utf8ToString(bytes, true);
}
function encodeBase64(bytes) {
if (bytes === undefined || bytes === null) {
return '';
}
if (bytes instanceof Array) {
bytes = bytes.filter(item => {
return Number.isFinite(item) && item >= 0 && item <= 255;
});
}
if (
!(
bytes instanceof Uint8Array ||
bytes instanceof Uint8ClampedArray ||
bytes instanceof Array
)
) {
if (typeof bytes === 'string') {
const str = bytes;
bytes = Array.from(unescape(encodeURIComponent(str))).map(ch =>
ch.codePointAt(0)
);
} else {
throw new TypeError('bytes must be of type Uint8Array or String.');
}
}
const keys = [
'A',
'B',
'C',
'D',
'E',
'F',
'G',
'H',
'I',
'J',
'K',
'L',
'M',
'N',
'O',
'P',
'Q',
'R',
'S',
'T',
'U',
'V',
'W',
'X',
'Y',
'Z',
'a',
'b',
'c',
'd',
'e',
'f',
'g',
'h',
'i',
'j',
'k',
'l',
'm',
'n',
'o',
'p',
'q',
'r',
's',
't',
'u',
'v',
'w',
'x',
'y',
'z',
'0',
'1',
'2',
'3',
'4',
'5',
'6',
'7',
'8',
'9',
'+',
'/'
];
const fillKey = '=';
let byte1;
let byte2;
let byte3;
let sign1 = ' ';
let sign2 = ' ';
let sign3 = ' ';
let sign4 = ' ';
let result = '';
for (let index = 0; index < bytes.length; ) {
let fillUpAt = 0;
// tslint:disable:no-increment-decrement
byte1 = bytes[index++];
byte2 = bytes[index++];
byte3 = bytes[index++];
if (byte2 === undefined) {
byte2 = 0;
fillUpAt = 2;
}
if (byte3 === undefined) {
byte3 = 0;
if (!fillUpAt) {
fillUpAt = 3;
}
}
// tslint:disable:no-bitwise
sign1 = keys[byte1 >> 2];
sign2 = keys[((byte1 & 0x3) << 4) + (byte2 >> 4)];
sign3 = keys[((byte2 & 0xf) << 2) + (byte3 >> 6)];
sign4 = keys[byte3 & 0x3f];
if (fillUpAt > 0) {
if (fillUpAt <= 2) {
sign3 = fillKey;
}
if (fillUpAt <= 3) {
sign4 = fillKey;
}
}
result += sign1 + sign2 + sign3 + sign4;
if (fillUpAt) {
break;
}
}
return result;
}
let base64 = encodeBase64("\u{1F604}"); // unicode code point escapes for smiley
let str = decodeBase64(base64);
console.log("base64", base64);
console.log("str", str);
document.body.innerText = str;
how to use it: decodeBase64(encodeBase64("\u{1F604}"))
A socket is basically an endpoint for network communication, consisting of at least an IP-address and a port. In Java/C# a socket is a higher level implementation of one side of a two-way connection.
Also, a definition in the Java documentation.
I know this is a couple of years late, but this is the 3rd Google response now for "Tkinter hide Label" as of 10/27/13... So if anyone like myself a few weeks ago is building a simple GUI and just wants some text to appear without swapping it out for another widget via "lower" or "lift" methods, I'd like to offer a workaround I use (Python2.7,Windows):
from Tkinter import *
class Top(Toplevel):
def __init__(self, parent, title = "How to Cheat and Hide Text"):
Toplevel.__init__(self,parent)
parent.geometry("250x250+100+150")
if title:
self.title(title)
parent.withdraw()
self.parent = parent
self.result = None
dialog = Frame(self)
self.initial_focus = self.dialog(dialog)
dialog.pack()
def dialog(self,parent):
self.parent = parent
self.L1 = Label(parent,text = "Hello, World!",state = DISABLED, disabledforeground = parent.cget('bg'))
self.L1.pack()
self.B1 = Button(parent, text = "Are You Alive???", command = self.hello)
self.B1.pack()
def hello(self):
self.L1['state']="normal"
if __name__ == '__main__':
root=Tk()
ds = Top(root)
root.mainloop()
The idea here is that you can set the color of the DISABLED text to the background ('bg') of the parent using ".cget('bg')" http://effbot.org/tkinterbook/widget.htm rendering it "invisible". The button callback resets the Label to the default foreground color and the text is once again visible.
Downsides here are that you still have to allocate the space for the text even though you can't read it, and at least on my computer, the text doesn't perfectly blend to the background. Maybe with some tweaking the color thing could be better and for compact GUIs, blank space allocation shouldn't be too much of a hassle for a short blurb.
See Default window colour Tkinter and hex colour codes for the info about how I found out about the color stuff.
UPDATE:
Time has changed, you can now remove (expire) TestFlight Builds as in this answer but you still cannot delete the build.
OLD:
I asked apple and here is their answer:
I understand you would like to remove a build from iTunes Connect as shown in your screenshot.
Please be advised this is expected behavior as you can remove a build from being the current build but you cannot delete it from iTunes Connect. For more information, please refer to the iTunes Connect Developer Guide: https://developer.apple.com/library/content/documentation/LanguagesUtilities/Conceptual/iTunesConnect_Guide/
So i just can't.
Here I am iterating each node and creating meaningful node names. If you notice, instanceOf Array and instanceOf Object pretty much does the same thing (in my application, i am giving different logic though)
function iterate(obj,parent_node) {
parent_node = parent_node || '';
for (var property in obj) {
if (obj.hasOwnProperty(property)) {
var node = parent_node + "/" + property;
if(obj[property] instanceof Array) {
//console.log('array: ' + node + ":" + obj[property]);
iterate(obj[property],node)
} else if(obj[property] instanceof Object){
//console.log('Object: ' + node + ":" + obj[property]);
iterate(obj[property],node)
}
else {
console.log(node + ":" + obj[property]);
}
}
}
}
note - I am inspired by Ondrej Svejdar's answer. But this solution has better performance and less ambiguous
The dat file has some lines of extra information before the actual data. Skip them with the skip
argument:
read.table("http://www.nilu.no/projects/ccc/onlinedata/ozone/CZ03_2009.dat",
header=TRUE, skip=3)
An easy way to check this if you are unfamiliar with the dataset is to first use readLines
to check a few lines, as below:
readLines("http://www.nilu.no/projects/ccc/onlinedata/ozone/CZ03_2009.dat",
n=10)
# [1] "Ozone data from CZ03 2009" "Local time: GMT + 0"
# [3] "" "Date Hour Value"
# [5] "01.01.2009 00:00 34.3" "01.01.2009 01:00 31.9"
# [7] "01.01.2009 02:00 29.9" "01.01.2009 03:00 28.5"
# [9] "01.01.2009 04:00 32.9" "01.01.2009 05:00 20.5"
Here, we can see that the actual data starts at [4]
, so we know to skip the first three lines.
If you really only wanted the Value
column, you could do that by:
as.vector(
read.table("http://www.nilu.no/projects/ccc/onlinedata/ozone/CZ03_2009.dat",
header=TRUE, skip=3)$Value)
Again, readLines
is useful for helping us figure out the actual name of the columns we will be importing.
But I don't see much advantage to doing that over reading the whole dataset in and extracting later.
Taken from lodash:
function isString(val) {
return typeof val === 'string' || ((!!val && typeof val === 'object') && Object.prototype.toString.call(val) === '[object String]');
}
console.log(isString('hello world!')); // true
console.log(isString(new String('hello world'))); // true
Using imagemagick, you can try:
convert page.png page.pdf
Or for multiple images:
convert page*.png mydoc.pdf
Try this regex "[-.]+"
. The + after treats consecutive delimiter chars as one. Remove plus if you do not want this.
Both methods achieve the same purpose, to forego unnecessary db queries. But they use different approaches for efficiency.
The only reason to use either of these methods is when a single large query is preferable to many small queries. Django uses the large query to create models in memory preemptively rather than performing on demand queries against the database.
select_related
performs a join with each lookup, but extends the select to include the columns of all joined tables. However this approach has a caveat.
Joins have the potential to multiply the number of rows in a query. When you perform a join over a foreign key or one-to-one field, the number of rows won't increase. However, many-to-many joins do not have this guarantee. So, Django restricts select_related
to relations that won't unexpectedly result in a massive join.
The "join in python" for prefetch_related
is a little more alarming then it should be. It creates a separate query for each table to be joined. It filters each of these table with a WHERE IN clause, like:
SELECT "credential"."id",
"credential"."uuid",
"credential"."identity_id"
FROM "credential"
WHERE "credential"."identity_id" IN
(84706, 48746, 871441, 84713, 76492, 84621, 51472);
Rather than performing a single join with potentially too many rows, each table is split into a separate query.
Tanuki changed license of jsw some time ago, if I was to begin a project, I would use Yet Another Java Service Wrapper, http://yajsw.sourceforge.net/ that is more or less an open source implementation that mimics JWS, and then builds on it and improves it even further.
EDIT: I have been using YAJSW for several years on several platorms (Windows, several linuxes...) and it is great, development is ongoing.
This is how you can draw a gray line at the end of your view (same idea as b123400's answer)
class CustomView: UIView {
override func draw(_ rect: CGRect) {
super.draw(rect)
if let context = UIGraphicsGetCurrentContext() {
context.setStrokeColor(UIColor.gray.cgColor)
context.setLineWidth(1)
context.move(to: CGPoint(x: 0, y: bounds.height))
context.addLine(to: CGPoint(x: bounds.width, y: bounds.height))
context.strokePath()
}
}
}
try below code
Directory.GetFiles(txtFolderPath.Text, "*ProfileHandler.cs",SearchOption.AllDirectories)
In Java, you can use char value with ":
char quotes ='"';
String strVar=quotes+"ROM"+quotes;
Abstract classes are classes that contain one or more abstract methods. Along with abstract methods, Abstract classes can have static, class and instance methods. But in case of interface, it will only have abstract methods not other. Hence it is not compulsory to inherit abstract class but it is compulsory to inherit interface.
NO NO NO !!!!!
it's simple, in MIUI 9.x you need developer settings ON and then
(Debugging section)
Then in Android select Runb app and choose your Xiaome phone
EDIT: you will also need allow installation from unknown sources
Have you tried with the custom format "#,##0.##"
?
The @Nadun's version did not work for me, sizing wasn't working well. Removed the direction="column"
or changing it to row
, helps with building vertical login forms with responsive sizing.
<Grid
container
spacing={0}
alignItems="center"
justify="center"
style={{ minHeight: "100vh" }}
>
<Grid item xs={6}></Grid>
</Grid>;
NUnit is probably the most supported by the 3rd party tools. It's also been around longer than the other three.
I personally don't care much about unit test frameworks, mocking libraries are IMHO much more important (and lock you in much more). Just pick one and stick with it.
Look at the Subfloats section of http://en.wikibooks.org/wiki/LaTeX/Floats,_Figures_and_Captions.
\begin{figure}[htp]
\centering
\label{figur}\caption{equation...}
\subfloat[Subcaption 1]{\label{figur:1}\includegraphics[width=60mm]{explicit3185.eps}}
\subfloat[Subcaption 2]{\label{figur:2}\includegraphics[width=60mm]{explicit3183.eps}}
\\
\subfloat[Subcaption 3]{\label{figur:3}\includegraphics[width=60mm]{explicit1501.eps}}
\subfloat[Subcaption 4]{\label{figur:4}\includegraphics[width=60mm]{explicit23185.eps}}
\\
\subfloat[Subcaption 5]{\label{figur:5}\includegraphics[width=60mm]{explicit23183.eps}}
\subfloat[Subcaption 6]{\label{figur:6}\includegraphics[width=60mm]{explicit21501.eps}}
\end{figure}
I use this query here to get all relevant info (relevant for me, at least :-)) from SQL Server:
SELECT
SERVERPROPERTY('productversion') as 'Product Version',
SERVERPROPERTY('productlevel') as 'Product Level',
SERVERPROPERTY('edition') as 'Product Edition',
SERVERPROPERTY('buildclrversion') as 'CLR Version',
SERVERPROPERTY('collation') as 'Default Collation',
SERVERPROPERTY('instancename') as 'Instance',
SERVERPROPERTY('lcid') as 'LCID',
SERVERPROPERTY('servername') as 'Server Name'
That gives you an output something like this:
Product Version Product Level Product Edition CLR Version
10.0.2531.0 SP1 Developer Edition (64-bit) v2.0.50727
Default Collation Instance LCID Server Name
Latin1_General_CI_AS NULL 1033 *********
A major part of test-driven development that is often glossed over is the writing of testable code. It seems like some kind of a compromise at first, but you'll discover that testable code is also ultimately modular, maintainable and readable. If you still need help convincing people this is a nice simple presentation about the advantages of unit testing.
If the date String does not include any value for hours, minutes and etc you cannot directly convert this to a LocalDateTime
. You can only convert it to a LocalDate
, because the string only represent the year,month and date components it would be the correct thing to do.
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyyMMdd");
LocalDate ld = LocalDate.parse("20180306", dtf); // 2018-03-06
Anyway you can convert this to LocalDateTime
.
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyyMMdd");
LocalDate ld = LocalDate.parse("20180306", dtf);
LocalDateTime ldt = LocalDateTime.of(ld, LocalTime.of(0,0)); // 2018-03-06T00:00
SELECT
COUNT(CASE WHEN rsp_ind = 0 then 1 ELSE NULL END) as "New",
COUNT(CASE WHEN rsp_ind = 1 then 1 ELSE NULL END) as "Accepted"
from tb_a
You can see the output for this request HERE
You can also serve on the next-highest available port doing something like this in Python:
import SimpleHTTPServer
import SocketServer
Handler = SimpleHTTPServer.SimpleHTTPRequestHandler
port = 8000
while True:
try:
httpd = SocketServer.TCPServer(('', port), Handler)
print 'Serving on port', port
httpd.serve_forever()
except SocketServer.socket.error as exc:
if exc.args[0] != 48:
raise
print 'Port', port, 'already in use'
port += 1
else:
break
If you need to do the same thing for other utilities, it may be more convenient as a bash script:
#!/usr/bin/env bash
MIN_PORT=${1:-1025}
MAX_PORT=${2:-65535}
(netstat -atn | awk '{printf "%s\n%s\n", $4, $4}' | grep -oE '[0-9]*$'; seq "$MIN_PORT" "$MAX_PORT") | sort -R | head -n 1
Set that up as a executable with the name get-free-port
and you can do something like this:
someprogram --port=$(get-free-port)
That's not as reliable as the native Python approach because the bash script doesn't capture the port -- another process could grab the port before your process does (race condition) -- but still may be useful enough when using a utility that doesn't have a try-try-again approach of its own.
If you're happy to ignore the time portion in the columns, DATEDIFF() will give you the difference you're looking for in days.
SELECT DATEDIFF('2010-10-08 18:23:13', '2010-09-21 21:40:36') AS days;
+------+
| days |
+------+
| 17 |
+------+
Create a POJO Java Class for the objects in the list like so:
class NameUrlClass{
private String name;
private String url;
//Constructor
public NameUrlClass(String name,String url){
this.name = name;
this.url = url;
}
}
Now simply create a List of NameUrlClass and initialize it to an ArrayList like so:
List<NameUrlClass> obj = new ArrayList<NameUrlClass>;
You can use store the JSON array in this object
obj = JSONArray;//[{"name":"name1","url":"url1"}{"name":"name2","url":"url2"},...]
You might want to take a look at these questions/answers ; they could give you some informations concerning your problem :
<iframe>
javascript access parent DOM across domains?To make things short : accessing iframe from another domain is not possible, for security reasons -- which explains the error message you are getting.
The Same origin policy page on wikipedia brings some informations about that security measure :
In a nutshell, the policy permits scripts running on pages originating from the same site to access each other's methods and properties with no specific restrictions — but prevents access to most methods and properties across pages on different sites.
A strict separation between content provided by unrelated sites must be maintained on client side to prevent the loss of data confidentiality or integrity.
ul {
padding-left: 0;
list-style-position: inside;
}
Explanation:
The first property padding-left: 0
clears the default padding/spacing for the ul
element while list-style-position: inside
makes the dots/bullets of li
aligned like a normal text.
So this code
<p>The ul element</p>
<ul>
asdfas
<li>Coffee</li>
<li>Tea</li>
<li>Milk</li>
</ul>
without any CSS will give us this:
but if we add in the CSS give at the top, that will give us this:
margin-left: auto works well. But clean flex box solution would be space-between in the main class. Space between works well if there is two or more elements. I have added a solution for single element as well.
.main { display: flex; justify-content: space-between; }
.a, .b, .c { background: #efefef; border: 1px solid #999; padding: 0.25rem; margin: 0.25rem;}
.b { flex: 1; text-align: center; }
.c-wrapper {
display: flex;
flex: 1;
justify-content: flex-end;
}
.c-wrapper2 {
display: flex;
flex: 1;
flex-flow: row-reverse;
}
_x000D_
<div class="main">
<div class="a"><a href="#">Home</a></div>
<div class="b"><a href="#">Some title centered</a></div>
<div class="c"><a href="#">Contact</a></div>
</div>
<div class="main">
<div class="a"><a href="#">Home</a></div>
<div class="c"><a href="#">Contact</a></div>
</div>
<div class="main">
<div class="c-wrapper">
<a class="c" href="#">Contact</a>
<a class="c" href="#">Contact2</a>
</div>
</div>
<div class="main">
<div class="c-wrapper2">
<span class="c">Contact</span>
<span class="c">Contact2</span>
</div>
</div>
_x000D_
Edit: fsw
has been merged into fswatch
. In this answer, any reference to fsw
should now read fswatch
.
I wrote an fswatch
replacement in C++ called fsw
which features several improvements:
It's a GNU Build System project which builds on any supported platform (OS X v. >= 10.6) with
./configure && make && sudo make install
Multiple paths can be passed as different arguments:
fsw file-0 ... file-n
It dumps a detailed record with all the event information such as:
Sat Feb 15 00:53:45 2014 - /path/to/file:inodeMetaMod modified isFile
Its output is easy to parse so that fsw
output can be piped to another process.
-l, --latency
.-n, --numeric
.strftime
format strings with -t, --time-format
.-u, --utc-time
.Getting fsw:
fsw
is hosted on GitHub and can be obtained cloning its repository:
git clone https://github.com/emcrisostomo/fsw
Installing fsw:
fsw
can be installed using the following commands:
./configure && make && sudo make install
Further information:
I also wrote an introductory blog post where you can find a couple of examples about how fsw
works.
For both Python 3 and Python 2, this works:
try:
from urllib.request import Request, urlopen # Python 3
except ImportError:
from urllib2 import Request, urlopen # Python 2
req = Request('http://api.company.com/items/details?country=US&language=en')
req.add_header('apikey', 'xxx')
content = urlopen(req).read()
print(content)
I think the easiest way for verifying an argument object is to use the refEq
method:
Mockito.verify(mockedObject).someMethodOnMockedObject(ArgumentMatchers.refEq(objectToCompareWith));
It can be used even if the object doesn't implement equals()
, because reflection is used. If you don't want to compare some fields, just add their names as arguments for refEq
.
--- create a ws server vs2012 upd 3
new project
choose .net framework 3.5
asp.net web service application
right click on the project root
choose add service reference
choose wsdl
--- how can I create a ws client from a wsdl file?
I´ve a ws server Axis2 under tomcat 7 and I want to test the compatibility
Try the below code:
Sub opendfiles()
Dim myfile As Variant
Dim counter As Integer
Dim path As String
myfolder = "D:\temp\"
ChDir myfolder
myfile = Application.GetOpenFilename(, , , , True)
counter = 1
If IsNumeric(myfile) = True Then
MsgBox "No files selected"
End If
While counter <= UBound(myfile)
path = myfile(counter)
Workbooks.Open path
counter = counter + 1
Wend
End Sub
Try this way i try in Android Studio 2.0
Step 1: File->Setting
Step 2: Seting->SDK option
Step 3: Click Edit option in Sdk Location
Step 4: Show "SDK Components Setup"
Step 5: Click on Three "..." in "SDK Components Wizad"
Step 6: Select your new SDK Path
ORDER BY: sort the data in ascending or descending order.
Consider the CUSTOMERS table:
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
| 2 | Khilan | 25 | Delhi | 1500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 4 | Chaitali | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
+----+----------+-----+-----------+----------+
Following is an example, which would sort the result in ascending order by NAME:
SQL> SELECT * FROM CUSTOMERS
ORDER BY NAME;
This would produce the following result:
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 4 | Chaitali | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 2 | Khilan | 25 | Delhi | 1500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
+----+----------+-----+-----------+----------+
GROUP BY: arrange identical data into groups.
Now, CUSTOMERS table has the following records with duplicate names:
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 1 | Ramesh | 32 | Ahmedabad | 2000.00 |
| 2 | Ramesh | 25 | Delhi | 1500.00 |
| 3 | kaushik | 23 | Kota | 2000.00 |
| 4 | kaushik | 25 | Mumbai | 6500.00 |
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
+----+----------+-----+-----------+----------+
if you want to group identical names into single name, then GROUP BY query would be as follows:
SQL> SELECT * FROM CUSTOMERS
GROUP BY NAME;
This would produce the following result: (for identical names it would pick the last one and finally sort the column in ascending order)
+----+----------+-----+-----------+----------+
| ID | NAME | AGE | ADDRESS | SALARY |
+----+----------+-----+-----------+----------+
| 5 | Hardik | 27 | Bhopal | 8500.00 |
| 4 | kaushik | 25 | Mumbai | 6500.00 |
| 6 | Komal | 22 | MP | 4500.00 |
| 7 | Muffy | 24 | Indore | 10000.00 |
| 2 | Ramesh | 25 | Delhi | 1500.00 |
+----+----------+-----+-----------+----------+
as you have inferred that it is of no use without SQL functions like sum,avg etc..
so go through this definition to understand the proper use of GROUP BY:
A GROUP BY clause works on the rows returned by a query by summarizing identical rows into a single/distinct group and returns a single row with the summary for each group, by using appropriate Aggregate function in the SELECT list, like COUNT(), SUM(), MIN(), MAX(), AVG(), etc.
Now, if you want to know the total amount of salary on each customer(name), then GROUP BY query would be as follows:
SQL> SELECT NAME, SUM(SALARY) FROM CUSTOMERS
GROUP BY NAME;
This would produce the following result: (sum of the salaries of identical names and sort the NAME column after removing identical names)
+---------+-------------+
| NAME | SUM(SALARY) |
+---------+-------------+
| Hardik | 8500.00 |
| kaushik | 8500.00 |
| Komal | 4500.00 |
| Muffy | 10000.00 |
| Ramesh | 3500.00 |
+---------+-------------+
The next()
method (offcial doc here) simply move the pointer of the result rows set to the next row (if it can). Anyway you can read this from the offcial doc as well:
Moves the cursor down one row from its current position.
This method return true if there's another row or false otherwise.
As Jim Garrison said in the comment, no obvious reason why you'd make a one-element list out of drug.upper()
(which implies drug is a string).
But that's not your error, as your function medications_minimum3()
doesn't even use the second argument (something you should fix).
TypeError: unhashable type: 'list'
usually means that you are trying to use a list as a hash argument (like for accessing a dictionary). I'd look for the error in counter[row[11]]+=1
-- are you sure that row[11]
is of the right type? Sounds to me it might be a list.
On strings and memory allocation:
A string in C is just a sequence of char
s, so you can use char *
or a char
array wherever you want to use a string data type:
typedef struct {
int number;
char *name;
char *address;
char *birthdate;
char gender;
} patient;
Then you need to allocate memory for the structure itself, and for each of the strings:
patient *createPatient(int number, char *name,
char *addr, char *bd, char sex) {
// Allocate memory for the pointers themselves and other elements
// in the struct.
patient *p = malloc(sizeof(struct patient));
p->number = number; // Scalars (int, char, etc) can simply be copied
// Must allocate memory for contents of pointers. Here, strdup()
// creates a new copy of name. Another option:
// p->name = malloc(strlen(name)+1);
// strcpy(p->name, name);
p->name = strdup(name);
p->address = strdup(addr);
p->birthdate = strdup(bd);
p->gender = sex;
return p;
}
If you'll only need a few patient
s, you can avoid the memory management at the expense of allocating more memory than you really need:
typedef struct {
int number;
char name[50]; // Declaring an array will allocate the specified
char address[200]; // amount of memory when the struct is created,
char birthdate[50]; // but pre-determines the max length and may
char gender; // allocate more than you need.
} patient;
On linked lists:
In general, the purpose of a linked list is to prove quick access to an ordered collection of elements. If your llist
contains an element called num
(which presumably contains the patient number), you need an additional data structure to hold the actual patient
s themselves, and you'll need to look up the patient number every time.
Instead, if you declare
typedef struct llist
{
patient *p;
struct llist *next;
} list;
then each element contains a direct pointer to a patient
structure, and you can access the data like this:
patient *getPatient(list *patients, int num) {
list *l = patients;
while (l != NULL) {
if (l->p->num == num) {
return l->p;
}
l = l->next;
}
return NULL;
}
I encountered this problem when I accidentally tried running my python module through the command prompt while my working directory was C:\Windows\System32
instead of the usual directory from which I run my python module
System.out.println(Name + " " + Income);
Is that what you mean? That will put a space between the name and the income?
DECLARE @T AS TABLE(pic_name VARCHAR(100));
INSERT INTO @T VALUES ('abc_1_2_3_4.gif'),('zzz_12_3_3_45.gif');
SELECT A.pic_name, P1.D, P2.D, P3.D, P4.D
FROM @T A
CROSS APPLY (SELECT NULLIF(CHARINDEX('_', A.pic_name),0) AS D) P1
CROSS APPLY (SELECT NULLIF(CHARINDEX('_', A.pic_name, P1.D+1), 0) AS D) P2
CROSS APPLY (SELECT NULLIF(CHARINDEX('_', A.pic_name, P2.D+1),0) AS D) P3
CROSS APPLY (SELECT NULLIF(CHARINDEX('_', A.pic_name, P3.D+1),0) AS D) P4
var src = $('img.conversation_img[alt="example"]').attr('src');
If you have multiple matching elements only the src of the first one will be returned.