Programs & Examples On #Member hiding

Declaring a class member in a derived class with the same name as a method in a base class.

Iterate over object in Angular

So I was going to implement my own helper function, objLength(obj), which returns just Object(obj).keys.length. But then when I was adding it to my template *ngIf function, my IDE suggested objectKeys(). I tried it, and it worked. Following it to its declaration, it appears to be offered by lib.es5.d.ts, so there you go!

Here's how I implemented it (I have a custom object that uses server-side generated keys as an index for files I've uploaded):

        <div *ngIf="fileList !== undefined && objectKeys(fileList).length > 0">
          <h6>Attached Files</h6>
          <table cellpadding="0" cellspacing="0">
            <tr *ngFor="let file of fileList | keyvalue">
              <td><a href="#">{{file.value['fileName']}}</a></td>
              <td class="actions">
                <a title="Delete File" (click)="deleteAFile(file.key);">
                </a>
              </td>
            </tr>
          </table>
        </div>

"Stack overflow in line 0" on Internet Explorer

I had this problem, and I solved it. There was an attribute in the <%@ Page tag named MaintainScrollPositionOnPostback and after removing it, the error disapeared. I added it before to prevent scrolling after each postback.

Fixed page header overlaps in-page anchors

I've got it working easily with CSS and HTML, using the "anchor:before" method mentioned above. I think it works the best, because it doesn't create massive padding between your divs.

.anchor:before {
  content:"";
  display:block;
  height:60px; /* fixed header height*/
  margin:-60px 0 0; /* negative fixed header height */
}

It doesn't seem to work for the first div on the page, but you can counter that by adding padding to that first div.

#anchor-one{padding-top: 60px;}

Here's a working fiddle: http://jsfiddle.net/FRpHE/24/

Mathematical functions in Swift

For people using swift [2.2] on Linux i.e. Ubuntu, the import is different!

The correct way to do this is to use Glibc. This is because on OS X and iOS, the basic Unix-like API's are in Darwin but in linux, these are located in Glibc. Importing Foundation won't help you here because it doesn't make the distinction by itself. To do this, you have to explicitly import it yourself:

#if os(macOS) || os(iOS)
import Darwin
#elseif os(Linux) || CYGWIN
import Glibc
#endif

You can follow the development of the Foundation framework here to learn more


EDIT: December 26th, 2018

As pointed out by @Cœur, starting from swift 3.0 some math functions are now part of the types themselves. For example, Double now has a squareRoot function. Similarly, ceil, floor, round, can all be achieved with Double.rounded(FloatingPointRoundingRule) -> Double.

Furthermore, I just downloaded and installed the latest stable version of swift on Ubuntu 18.04, and it looks like Foundation framework is all you need to import to have access to the math functions now. I tried finding documentation for this, but nothing came up.

? swift          
Welcome to Swift version 4.2.1 (swift-4.2.1-RELEASE). Type :help for assistance.
  1> sqrt(9)
error: repl.swift:1:1: error: use of unresolved identifier 'sqrt'
sqrt(9)
^~~~


  1> import Foundation
  2> sqrt(9)
$R0: Double = 3
  3> floor(9.3)
$R1: Double = 9
  4> ceil(9.3) 
$R2: Double = 10

Pass a PHP string to a JavaScript variable (and escape newlines)

I have had a similar issue and understand that the following is the best solution:

<script>
    var myvar = decodeURIComponent("<?php echo rawurlencode($myVarValue); ?>");
</script>

However, the link that micahwittman posted suggests that there are some minor encoding differences. PHP's rawurlencode() function is supposed to comply with RFC 1738, while there appear to have been no such effort with Javascript's decodeURIComponent().

What is the difference between public, protected, package-private and private in Java?

The difference can be found in the links already provided but which one to use usually comes down to the "Principle of Least Knowledge". Only allow the least visibility that is needed.

How to include Javascript file in Asp.Net page

add like

<head runat="server">
<script src="Registration.js" type="text/javascript"></script>
</head>

OR can add in code behind.

Page.ClientScript.RegisterClientScriptInclude("Registration", ResolveUrl("~/js/Registration.js"));

Read text from response

The accepted answer does not correctly dispose the WebResponse or decode the text. Also, there's a new way to do this in .NET 4.5.

To perform an HTTP GET and read the response text, do the following.

.NET 1.1 - 4.0

public static string GetResponseText(string address)
{
    var request = (HttpWebRequest)WebRequest.Create(address);

    using (var response = (HttpWebResponse)request.GetResponse())
    {
        var encoding = Encoding.GetEncoding(response.CharacterSet);

        using (var responseStream = response.GetResponseStream())
        using (var reader = new StreamReader(responseStream, encoding))
            return reader.ReadToEnd();
    }
}

.NET 4.5

private static readonly HttpClient httpClient = new HttpClient();

public static async Task<string> GetResponseText(string address)
{
    return await httpClient.GetStringAsync(address);
}

Combining paste() and expression() functions in plot labels

If x^2 and y^2 were expressions already given in the variable squared, this solves the problem:

labNames <- c('xLab','yLab')
squared <- c(expression('x'^2), expression('y'^2))

xlab <- eval(bquote(expression(.(labNames[1]) ~ .(squared[1][[1]]))))
ylab <- eval(bquote(expression(.(labNames[2]) ~ .(squared[2][[1]]))))

plot(c(1:10), xlab = xlab, ylab = ylab)

Please note the [[1]] behind squared[1]. It gives you the content of "expression(...)" between the brackets without any escape characters.

Setting a minimum/maximum character count for any character using a regular expression

If you also want to match newlines, then you might want to use "^[\s\S]{1,35}$" (depending on the regex engine). Otherwise, as others have said, you should used "^.{1,35}$"

How to handle the new window in Selenium WebDriver using Java?

Set<String> windows = driver.getWindowHandles();
Iterator<String> itr = windows.iterator();

//patName will provide you parent window
String patName = itr.next();

//chldName will provide you child window
String chldName = itr.next();

//Switch to child window
driver.switchto().window(chldName);

//Do normal selenium code for performing action in child window

//To come back to parent window
driver.switchto().window(patName);

AngularJS : How do I switch views from a controller function?

Firstly you have to create state in app.js as below

.state('login', {
      url: '/',
      templateUrl: 'views/login.html',
      controller: 'LoginCtrl'
    })

and use below code in controller

 $location.path('login'); 

Hope this will help you

Get month name from number

I created my own function converting numbers to their corresponding month.

def month_name (number):
    if number == 1:
        return "January"
    elif number == 2:
        return "February"
    elif number == 3:
        return "March"
    elif number == 4:
        return "April"
    elif number == 5:
        return "May"
    elif number == 6:
        return "June"
    elif number == 7:
        return "July"
    elif number == 8:
        return "August"
    elif number == 9:
        return "September"
    elif number == 10:
        return "October"
    elif number == 11:
        return "November"
    elif number == 12:
        return "December"

Then I can call the function. For example:

print (month_name (12))

Outputs:

>>> December

Shortcuts in Objective-C to concatenate NSStrings

When building requests for web services, I find doing something like the following is very easy and makes concatenation readable in Xcode:

NSString* postBody = {
    @"<?xml version=\"1.0\" encoding=\"utf-8\"?>"
    @"<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">"
    @" <soap:Body>"
    @"  <WebServiceMethod xmlns=\"\">"
    @"   <parameter>test</parameter>"
    @"  </WebServiceMethod>"
    @" </soap:Body>"
    @"</soap:Envelope>"
};

How can I combine flexbox and vertical scroll in a full-height app?

The current spec says this regarding flex: 1 1 auto:

Sizes the item based on the width/height properties, but makes them fully flexible, so that they absorb any free space along the main axis. If all items are either flex: auto, flex: initial, or flex: none, any positive free space after the items have been sized will be distributed evenly to the items with flex: auto.

http://www.w3.org/TR/2012/CR-css3-flexbox-20120918/#flex-common

It sounds to me like if you say an element is 100px tall, it is treated more like a "suggested" size, not an absolute. Because it is allowed to shrink and grow, it takes up as much space as its allowed to. That's why adding this line to your "main" element works: height: 0 (or any other smallish number).

CSV API for Java

For the last enterprise application I worked on that needed to handle a notable amount of CSV -- a couple of months ago -- I used SuperCSV at sourceforge and found it simple, robust and problem-free.

AJAX jQuery refresh div every 5 seconds

you can use this one.

<div id="test"></div>

you java script code should be like that.

setInterval(function(){
      $('#test').load('test.php');
 },5000);

Sending HTTP POST Request In Java

String rawData = "id=10";
String type = "application/x-www-form-urlencoded";
String encodedData = URLEncoder.encode( rawData, "UTF-8" ); 
URL u = new URL("http://www.example.com/page.php");
HttpURLConnection conn = (HttpURLConnection) u.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setRequestProperty( "Content-Type", type );
conn.setRequestProperty( "Content-Length", String.valueOf(encodedData.length()));
OutputStream os = conn.getOutputStream();
os.write(encodedData.getBytes());

Why is using the JavaScript eval function a bad idea?

This may become more of an issue as the next generation of browsers come out with some flavor of a JavaScript compiler. Code executed via Eval may not perform as well as the rest of your JavaScript against these newer browsers. Someone should do some profiling.

Https to http redirect using htaccess

Your code is correct. Just put them inside the <VirtualHost *:443>

Example:

<VirtualHost *:443>
  SSLEnable

  RewriteEngine On
  RewriteCond %{HTTPS} on
  RewriteRule (.*) http://%{HTTP_HOST}%{REQUEST_URI}

</VirtualHost>

Difference between $(this) and event.target?

There is a difference between $(this) and event.target, and quite a significant one. While this (or event.currentTarget, see below) always refers to the DOM element the listener was attached to, event.target is the actual DOM element that was clicked. Remember that due to event bubbling, if you have

<div class="outer">
  <div class="inner"></div>
</div>

and attach click listener to the outer div

$('.outer').click( handler );

then the handler will be invoked when you click inside the outer div as well as the inner one (unless you have other code that handles the event on the inner div and stops propagation).

In this example, when you click inside the inner div, then in the handler:

  • this refers to the .outer DOM element (because that's the object to which the handler was attached)
  • event.currentTarget also refers to the .outer element (because that's the current target element handling the event)
  • event.target refers to the .inner element (this gives you the element where the event originated)

The jQuery wrapper $(this) only wraps the DOM element in a jQuery object so you can call jQuery functions on it. You can do the same with $(event.target).

Also note that if you rebind the context of this (e.g. if you use Backbone it's done automatically), it will point to something else. You can always get the actual DOM element from event.currentTarget.

getting the index of a row in a pandas apply function

To answer the original question: yes, you can access the index value of a row in apply(). It is available under the key name and requires that you specify axis=1 (because the lambda processes the columns of a row and not the rows of a column).

Working example (pandas 0.23.4):

>>> import pandas as pd
>>> df = pd.DataFrame([[1,2,3],[4,5,6]], columns=['a','b','c'])
>>> df.set_index('a', inplace=True)
>>> df
   b  c
a      
1  2  3
4  5  6
>>> df['index_x10'] = df.apply(lambda row: 10*row.name, axis=1)
>>> df
   b  c  index_x10
a                 
1  2  3         10
4  5  6         40

Create a map with clickable provinces/states using SVG, HTML/CSS, ImageMap

jQuery plugin for decorating image maps (highlights, select areas, tooltips):

http://www.outsharked.com/imagemapster/

Disclosure: I wrote it.

Using awk to print all columns from the nth to the last

Because of a wrong most upvoted anwser with 340 votes, I just lost 5 minutes of my life! Did anybody try this answer out before upvoting this? Apparantly not. Completely useless.

I have a log where after $5 with an IP address can be more text or no text. I need everything from the IP address to the end of the line should there be anything after $5. In my case, this is actualy withn an awk program, not an awk oneliner so awk must solve the problem. When I try to remove the first 4 fields using the most upvoted but completely wrong answer:

echo "  7 27.10.16. Thu 11:57:18 37.244.182.218" | awk '{$1=$2=$3=$4=""; printf "[%s]\n", $0}'

it spits out wrong and useless response (I added [..] to demonstrate):

[    37.244.182.218 one two three]

There are even some sugestions to combine substr with this wrong answer. Like that complication is an improvement.

Instead, if columns are fixed width until the cut point and awk is needed, the correct answer is:

echo "  7 27.10.16. Thu 11:57:18 37.244.182.218" | awk '{printf "[%s]\n", substr($0,28)}'

which produces the desired output:

[37.244.182.218 one two three]

How to set default values for Angular 2 component properties?

That is interesting subject. You can play around with two lifecycle hooks to figure out how it works: ngOnChanges and ngOnInit.

Basically when you set default value to Input that's mean it will be used only in case there will be no value coming on that component. And the interesting part it will be changed before component will be initialized.

Let's say we have such components with two lifecycle hooks and one property coming from input.

@Component({
  selector: 'cmp',
})
export class Login implements OnChanges, OnInit {
  @Input() property: string = 'default';

  ngOnChanges(changes) {
    console.log('Changed', changes.property.currentValue, changes.property.previousValue);
  }

  ngOnInit() {
    console.log('Init', this.property);
  }

}

Situation 1

Component included in html without defined property value

As result we will see in console: Init default

That's mean onChange was not triggered. Init was triggered and property value is default as expected.

Situation 2

Component included in html with setted property <cmp [property]="'new value'"></cmp>

As result we will see in console:

Changed new value Object {}

Init new value

And this one is interesting. Firstly was triggered onChange hook, which setted property to new value, and previous value was empty object! And only after that onInit hook was triggered with new value of property.

Stratified Train/Test-split in scikit-learn

#train_size is 1 - tst_size - vld_size
tst_size=0.15
vld_size=0.15

X_train_test, X_valid, y_train_test, y_valid = train_test_split(df.drop(y, axis=1), df.y, test_size = vld_size, random_state=13903) 

X_train_test_V=pd.DataFrame(X_train_test)
X_valid=pd.DataFrame(X_valid)

X_train, X_test, y_train, y_test = train_test_split(X_train_test, y_train_test, test_size=tst_size, random_state=13903)

UIView frame, bounds and center

This question already has a good answer, but I want to supplement it with some more pictures. My full answer is here.

To help me remember frame, I think of a picture frame on a wall. Just like a picture can be moved anywhere on the wall, the coordinate system of a view's frame is the superview. (wall=superview, frame=view)

To help me remember bounds, I think of the bounds of a basketball court. The basketball is somewhere within the court just like the coordinate system of the view's bounds is within the view itself. (court=view, basketball/players=content inside the view)

Like the frame, view.center is also in the coordinates of the superview.

Frame vs Bounds - Example 1

The yellow rectangle represents the view's frame. The green rectangle represents the view's bounds. The red dot in both images represents the origin of the frame or bounds within their coordinate systems.

Frame
    origin = (0, 0)
    width = 80
    height = 130

Bounds 
    origin = (0, 0)
    width = 80
    height = 130

enter image description here


Example 2

Frame
    origin = (40, 60)  // That is, x=40 and y=60
    width = 80
    height = 130

Bounds 
    origin = (0, 0)
    width = 80
    height = 130

enter image description here


Example 3

Frame
    origin = (20, 52)  // These are just rough estimates.
    width = 118
    height = 187

Bounds 
    origin = (0, 0)
    width = 80
    height = 130

enter image description here


Example 4

This is the same as example 2, except this time the whole content of the view is shown as it would look like if it weren't clipped to the bounds of the view.

Frame
    origin = (40, 60)
    width = 80
    height = 130

Bounds 
    origin = (0, 0)
    width = 80
    height = 130

enter image description here


Example 5

Frame
    origin = (40, 60)
    width = 80
    height = 130

Bounds 
    origin = (280, 70)
    width = 80
    height = 130

enter image description here

Again, see here for my answer with more details.

header location not working in my php code

In my case i created new config file with function 'ob_start()' and added this to my .gitignore file.

Array[n] vs Array[10] - Initializing array with variable vs real number

In C++, variable length arrays are not legal. G++ allows this as an "extension" (because C allows it), so in G++ (without being -pedantic about following the C++ standard), you can do:

int n = 10;
double a[n]; // Legal in g++ (with extensions), illegal in proper C++

If you want a "variable length array" (better called a "dynamically sized array" in C++, since proper variable length arrays aren't allowed), you either have to dynamically allocate memory yourself:

int n = 10;
double* a = new double[n]; // Don't forget to delete [] a; when you're done!

Or, better yet, use a standard container:

int n = 10;
std::vector<double> a(n); // Don't forget to #include <vector>

If you still want a proper array, you can use a constant, not a variable, when creating it:

const int n = 10;
double a[n]; // now valid, since n isn't a variable (it's a compile time constant)

Similarly, if you want to get the size from a function in C++11, you can use a constexpr:

constexpr int n()
{
    return 10;
}

double a[n()]; // n() is a compile time constant expression

How to call getResources() from a class which has no context?

It can easily be done if u had declared a class that extends from Application

This class will be like a singleton, so when u need a context u can get it just like this:

I think this is the better answer and the cleaner

Here is my code from Utilities package:

 public static String getAppNAme(){
     return MyOwnApplication.getInstance().getString(R.string.app_name);
 }

Java: How to convert String[] to List or Set

The easiest way would be:

String[] myArray = ...;
List<String> strs = Arrays.asList(myArray);

using the handy Arrays utility class. Note, that you can even do

List<String> strs = Arrays.asList("a", "b", "c");

Replace \n with <br />

The Problem is When you denote '\n' in the replace() call , '\n' is treated as a String length=4 made out of ' \ n '
To get rid of this, use ascii notation. http://www.asciitable.com/

example:

newLine = chr(10)
thatLine=thatLine.replace(newLine , '<br />')

print(thatLine) #python3

print thatLine #python2 .

Initialize a string in C to empty string

In addition to Will Dean's version, the following are common for whole buffer initialization:

char s[10] = {'\0'};

or

char s[10];
memset(s, '\0', sizeof(s));

or

char s[10];
strncpy(s, "", sizeof(s));

Maven: add a folder or jar file into current classpath

This might have been asked before. See Can I add jars to maven 2 build classpath without installing them?

In a nutshell: include your jar as dependency with system scope. This requires specifying the absolute path to the jar.

See also http://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html

How can I install packages using pip according to the requirements.txt file from a local directory?

First of all, create a virtual environment.

In Python 3.6

virtualenv --python=/usr/bin/python3.6 <path/to/new/virtualenv/>

In Python 2.7

virtualenv --python=/usr/bin/python2.7 <path/to/new/virtualenv/>

Then activate the environment and install all the packages available in the requirement.txt file.

source <path/to/new/virtualenv>/bin/activate
pip install -r <path/to/requirement.txt>

How Big can a Python List Get?

According to the source code, the maximum size of a list is PY_SSIZE_T_MAX/sizeof(PyObject*).

PY_SSIZE_T_MAX is defined in pyport.h to be ((size_t) -1)>>1

On a regular 32bit system, this is (4294967295 / 2) / 4 or 536870912.

Therefore the maximum size of a python list on a 32 bit system is 536,870,912 elements.

As long as the number of elements you have is equal or below this, all list functions should operate correctly.

Link vs compile vs controller

  • compile: used when we need to modify directive template, like add new expression, append another directive inside this directive
  • controller: used when we need to share/reuse $scope data
  • link: it is a function which used when we need to attach event handler or to manipulate DOM.

Send Message in C#

You don't need to send messages.

Add an event to the one form and an event handler to the other. Then you can use a third project which references the other two to attach the event handler to the event. The two DLLs don't need to reference each other for this to work.

Parenthesis/Brackets Matching using Stack algorithm

//basic code non strack algorithm just started learning java ignore space and time.
/// {[()]}[][]{}
// {[( -a -> }]) -b -> replace a(]}) -> reverse a( }]))-> 
//Split string to substring {[()]}, next [], next [], next{}

public class testbrackets {
    static String stringfirst;
    static String stringsecond;
    static int open = 0;
    public static void main(String[] args) {
        splitstring("(()){}()");
    }
static void splitstring(String str){

    int len = str.length();
    for(int i=0;i<=len-1;i++){
        stringfirst="";
        stringsecond="";
        System.out.println("loop starttttttt");
        char a = str.charAt(i);
    if(a=='{'||a=='['||a=='(')
    {
        open = open+1;
        continue;
    }
    if(a=='}'||a==']'||a==')'){
        if(open==0){
            System.out.println(open+"started with closing brace");
            return;
        }
        String stringfirst=str.substring(i-open, i);
        System.out.println("stringfirst"+stringfirst);
        String stringsecond=str.substring(i, i+open);
        System.out.println("stringsecond"+stringsecond);
        replace(stringfirst, stringsecond);

        }
    i=(i+open)-1;
    open=0;
    System.out.println(i);
    }
    }
    static void replace(String stringfirst, String stringsecond){
        stringfirst = stringfirst.replace('{', '}');
        stringfirst = stringfirst.replace('(', ')');
        stringfirst = stringfirst.replace('[', ']');
        StringBuilder stringfirst1 = new StringBuilder(stringfirst);
        stringfirst = stringfirst1.reverse().toString();
    System.out.println("stringfirst"+stringfirst);
    System.out.println("stringsecond"+stringsecond);
if(stringfirst.equals(stringsecond)){
    System.out.println("pass");
}
    else{
        System.out.println("fail");
        System.exit(0);
        }
    }
}

UIAlertView first deprecated IOS 9

 UIAlertController * alert = [UIAlertController
                                 alertControllerWithTitle:@"Are you sure you want to logout?"
                                 message:@""
                                 preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction* yesButton = [UIAlertAction
                                actionWithTitle:@"Logout"
                                style:UIAlertActionStyleDestructive
                                handler:^(UIAlertAction * action)
                                {

                                }];

    UIAlertAction* noButton = [UIAlertAction
                               actionWithTitle:@"Cancel"
                               style:UIAlertActionStyleDefault
                               handler:^(UIAlertAction * action) {
                                   //Handle no, thanks button
                               }];

    [alert addAction:noButton];
    [alert addAction:yesButton];

    [self presentViewController:alert animated:YES completion:nil];

Apply function to each column in a data frame observing each columns existing data type

The reason that max works with apply is that apply is coercing your data frame to a matrix first, and a matrix can only hold one data type. So you end up with a matrix of characters. sapply is just a wrapper for lapply, so it is not surprising that both yield the same error.

The default behavior when you create a data frame is for categorical columns to be stored as factors. Unless you specify that it is an ordered factor, operations like max and min will be undefined, since R is assuming that you've created an unordered factor.

You can change this behavior by specifying options(stringsAsFactors = FALSE), which will change the default for the entire session, or you can pass stringsAsFactors = FALSE in the data.frame() construction call itself. Note that this just means that min and max will assume "alphabetical" ordering by default.

Or you can manually specify an ordering for each factor, although I doubt that's what you want to do.

Regardless, sapply will generally yield an atomic vector, which will entail converting everything to characters in many cases. One way around this is as follows:

#Some test data
d <- data.frame(v1 = runif(10), v2 = letters[1:10], 
                v3 = rnorm(10), v4 = LETTERS[1:10],stringsAsFactors = TRUE)

d[4,] <- NA

#Similar function to DWin's answer          
fun <- function(x){
    if(is.numeric(x)){max(x,na.rm = 1)}
    else{max(as.character(x),na.rm=1)}
}   

#Use colwise from plyr package
colwise(fun)(d)
         v1 v2       v3 v4
1 0.8478983  j 1.999435  J

Parse a URI String into Name-Value Collection

On Android, there is a Uri class in package android.net . Note that Uri is part of android.net, while URI is part of java.net .

Uri class has many functions to extract key-value pairs from a query. enter image description here

Following function returns key-value pairs in the form of HashMap.

In Java:

Map<String, String> getQueryKeyValueMap(Uri uri){
    HashMap<String, String> keyValueMap = new HashMap();
    String key;
    String value;

    Set<String> keyNamesList = uri.getQueryParameterNames();
    Iterator iterator = keyNamesList.iterator();

    while (iterator.hasNext()){
        key = (String) iterator.next();
        value = uri.getQueryParameter(key);
        keyValueMap.put(key, value);
    }
    return keyValueMap;
}

In Kotlin:

fun getQueryKeyValueMap(uri: Uri): HashMap<String, String> {
        val keyValueMap = HashMap<String, String>()
        var key: String
        var value: String

        val keyNamesList = uri.queryParameterNames
        val iterator = keyNamesList.iterator()

        while (iterator.hasNext()) {
            key = iterator.next() as String
            value = uri.getQueryParameter(key) as String
            keyValueMap.put(key, value)
        }
        return keyValueMap
    }

How is a CRC32 checksum calculated?

For IEEE802.3, CRC-32. Think of the entire message as a serial bit stream, append 32 zeros to the end of the message. Next, you MUST reverse the bits of EVERY byte of the message and do a 1's complement the first 32 bits. Now divide by the CRC-32 polynomial, 0x104C11DB7. Finally, you must 1's complement the 32-bit remainder of this division bit-reverse each of the 4 bytes of the remainder. This becomes the 32-bit CRC that is appended to the end of the message.

The reason for this strange procedure is that the first Ethernet implementations would serialize the message one byte at a time and transmit the least significant bit of every byte first. The serial bit stream then went through a serial CRC-32 shift register computation, which was simply complemented and sent out on the wire after the message was completed. The reason for complementing the first 32 bits of the message is so that you don't get an all zero CRC even if the message was all zeros.

MYSQL into outfile "access denied" - but my user has "ALL" access.. and the folder is CHMOD 777

As @fijaaron says,

  1. GRANT ALL does not imply GRANT FILE
  2. GRANT FILE only works with *.*

So do

GRANT FILE ON *.* TO user;

need to add a class to an element

You probably need something like:

result.className = 'red'; 

In pure JavaScript you should use className to deal with classes. jQuery has an abstraction called addClass for it.

Open page in new window without popup blocking

As a general rule, pop up blockers target windows that launch without user interaction. Usually a click event can open a window without it being blocked. (unless it's a really bad popup blocker)

Try launching after a click event

How to stop execution after a certain time in Java?

If you can't go over your time limit (it's a hard limit) then a thread is your best bet. You can use a loop to terminate the thread once you get to the time threshold. Whatever is going on in that thread at the time can be interrupted, allowing calculations to stop almost instantly. Here is an example:

Thread t = new Thread(myRunnable); // myRunnable does your calculations

long startTime = System.currentTimeMillis();
long endTime = startTime + 60000L;

t.start(); // Kick off calculations

while (System.currentTimeMillis() < endTime) {
    // Still within time theshold, wait a little longer
    try {
         Thread.sleep(500L);  // Sleep 1/2 second
    } catch (InterruptedException e) {
         // Someone woke us up during sleep, that's OK
    }
}

t.interrupt();  // Tell the thread to stop
t.join();       // Wait for the thread to cleanup and finish

That will give you resolution to about 1/2 second. By polling more often in the while loop, you can get that down.

Your runnable's run would look something like this:

public void run() {
    while (true) {
        try {
            // Long running work
            calculateMassOfUniverse();
        } catch (InterruptedException e) {
            // We were signaled, clean things up
            cleanupStuff();
            break;           // Leave the loop, thread will exit
    }
}

Update based on Dmitri's answer

Dmitri pointed out TimerTask, which would let you avoid the loop. You could just do the join call and the TimerTask you setup would take care of interrupting the thread. This would let you get more exact resolution without having to poll in a loop.

creating array without declaring the size - java

How about this

    private Object element[] = new Object[] {};

Bulk create model objects in django

for a single line implementation, you can use a lambda expression in a map

map(lambda x:MyModel.objects.get_or_create(name=x), items)

Here, lambda matches each item in items list to x and create a Database record if necessary.

Lambda Documentation

Swift Beta performance: sorting arrays

func partition(inout list : [Int], low: Int, high : Int) -> Int {
    let pivot = list[high]
    var j = low
    var i = j - 1
    while j < high {
        if list[j] <= pivot{
            i += 1
            (list[i], list[j]) = (list[j], list[i])
        }
        j += 1
    }
    (list[i+1], list[high]) = (list[high], list[i+1])
    return i+1
}

func quikcSort(inout list : [Int] , low : Int , high : Int) {

    if low < high {
        let pIndex = partition(&list, low: low, high: high)
        quikcSort(&list, low: low, high: pIndex-1)
        quikcSort(&list, low: pIndex + 1, high: high)
    }
}

var list = [7,3,15,10,0,8,2,4]
quikcSort(&list, low: 0, high: list.count-1)

var list2 = [ 10, 0, 3, 9, 2, 14, 26, 27, 1, 5, 8, -1, 8 ]
quikcSort(&list2, low: 0, high: list2.count-1)

var list3 = [1,3,9,8,2,7,5]
quikcSort(&list3, low: 0, high: list3.count-1) 

This is my Blog about Quick Sort- Github sample Quick-Sort

You can take a look at Lomuto's partitioning algorithm in Partitioning the list. Written in Swift.

Extracting columns from text file with different delimiters in Linux

If the command should work with both tabs and spaces as the delimiter I would use awk:

awk '{print $100,$101,$102,$103,$104,$105}' myfile > outfile

As long as you just need to specify 5 fields it is imo ok to just type them, for longer ranges you can use a for loop:

awk '{for(i=100;i<=105;i++)print $i}' myfile > outfile

If you want to use cut, you need to use the -f option:

cut -f100-105 myfile > outfile

If the field delimiter is different from TAB you need to specify it using -d:

cut -d' ' -f100-105 myfile > outfile

Check the man page for more info on the cut command.

Best method for reading newline delimited files and discarding the newlines?

I'd do it like this:

f = open('test.txt')
l = [l for l in f.readlines() if l.strip()]
f.close()
print l

How to connect to mysql with laravel?

Laravel makes it very easy to manage your database connections through app/config/database.php.

As you noted, it is looking for a database called 'database'. The reason being that this is the default name in the database configuration file.

'mysql' => array(
    'driver'    => 'mysql',
    'host'      => 'localhost',
    'database'  => 'database', <------ Default name for database
    'username'  => 'root',
    'password'  => '',
    'charset'   => 'utf8',
    'collation' => 'utf8_unicode_ci',
    'prefix'    => '',
),

Change this to the name of the database that you would like to connect to like this:

'mysql' => array(
    'driver'    => 'mysql',
    'host'      => 'localhost',
    'database'  => 'my_awesome_data', <------ change name for database
    'username'  => 'root',            <------ remember credentials
    'password'  => '',
    'charset'   => 'utf8',
    'collation' => 'utf8_unicode_ci',
    'prefix'    => '',
),

Once you have this configured correctly you will easily be able to access your database!

Happy Coding!

Open multiple Projects/Folders in Visual Studio Code

Just put your projects in the same folder and simply open that folder in vscode.

Now your projects will appear like:

GROUP OF PROJECTS

  • PROJECT 1

    • Contents
    • Contents
  • PROJECT 2

    • Contents
    • Contents

How to find list of possible words from a letter matrix [Boggle Solver]

I know I am really late at the party but I have implemented, as a coding exercise, a boggle solver in several programming languages (C++, Java, Go, C#, Python, Ruby, JavaScript, Julia, Lua, PHP, Perl) and I thought that someone might be interested in those, so I leave link here: https://github.com/AmokHuginnsson/boggle-solvers

MySQL direct INSERT INTO with WHERE clause

Example of how to perform a INSERT INTO SELECT with a WHERE clause.

INSERT INTO #test2 (id) SELECT id FROM #test1 WHERE id > 2

How to set a session variable when clicking a <a> link

I had the same problem - i wanted to pass a parameter to another page by clicking a hyperlink and get the value to go to the next page (without using GET because the parameter is stored in the URL).

to those who don't understand why you would want to do this the answer is you dont want the user to see sensitive information or you dont want someone editing the GET.

well after scouring the internet it seemed it wasnt possible to make a normal hyperlink using the POST method.

And then i had a eureka moment!!!! why not just use CSS to make the submit button look like a normal hyperlink??? ...and put the value i want to pass in a hidden field

i tried it and it works. you can see an exaple here http://paulyouthed.com/test/css-button-that-looks-like-hyperlink.php

the basic code for the form is:

    <form enctype="multipart/form-data" action="page-to-pass-to.php" method="post">
                        <input type="hidden" name="post-variable-name" value="value-you-want-pass"/>
                        <input type="submit" name="whatever" value="text-to-display" id="hyperlink-style-button"/>
                </form>

the basic css is:

    #hyperlink-style-button{
      background:none;
      border:0;
      color:#666;
      text-decoration:underline;
    }

    #hyperlink-style-button:hover{
      background:none;
      border:0;
      color:#666;
      text-decoration:none;
      cursor:pointer;
      cursor:hand;
    }

How to sum the values of one column of a dataframe in spark/scala

Using spark sql query..just incase if it helps anyone!

import org.apache.spark.sql.SparkSession 
import org.apache.spark.SparkConf 
import org.apache.spark.sql.functions._ 
import org.apache.spark.SparkContext 
import java.util.stream.Collectors

val conf = new SparkConf().setMaster("local[2]").setAppName("test")
val spark = SparkSession.builder.config(conf).getOrCreate()
val df = spark.sparkContext.parallelize(Seq(1, 2, 3, 4, 5, 6, 7)).toDF()

df.createOrReplaceTempView("steps")
val sum = spark.sql("select  sum(steps) as stepsSum from steps").map(row => row.getAs("stepsSum").asInstanceOf[Long]).collect()(0)
println("steps sum = " + sum) //prints 28

C: socket connection timeout

On Linux you can also use:

struct timeval timeout;
timeout.tv_sec  = 7;  // after 7 seconds connect() will timeout
timeout.tv_usec = 0;
setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
connect(...)

Don't forget to clear SO_SNDTIMEO after connect() if you don't need it.

build maven project with propriatery libraries included

You can use the maven-assembly-plugin and create a jar with all dependencies included.

JQuery Validate input file type

One the elements are added, use the rules method to add the rules

//bug fixed thanks to @Sparky
$('input[name^="fileupload"]').each(function () {
    $(this).rules('add', {
        required: true,
        accept: "image/jpeg, image/pjpeg"
    })
})

Demo: Fiddle


Update

var filenumber = 1;
$("#AddFile").click(function () { //User clicks button #AddFile
    var $li = $('<li><input type="file" name="FileUpload' + filenumber + '" id="FileUpload' + filenumber + '" required=""/> <a href="#" class="RemoveFileUpload">Remove</a></li>').prependTo("#FileUploader");

    $('#FileUpload' + filenumber).rules('add', {
        required: true,
        accept: "image/jpeg, image/pjpeg"
    })

    filenumber++;
    return false;
});

How to change default text color using custom theme?

When you create an App, a file called styles.xml will be created in your res/values folder. If you change the styles, you can change the background, text color, etc for all your layouts. That way you don’t have to go into each individual layout and change the it manually.

styles.xml:

<resources xmlns:android="http://schemas.android.com/apk/res/android">
<style name="Theme.AppBaseTheme" parent="@android:style/Theme.Light">
    <item name="android:editTextColor">#295055</item> 
    <item name="android:textColorPrimary">#295055</item>
    <item name="android:textColorSecondary">#295055</item>
    <item name="android:textColorTertiary">#295055</item>
    <item name="android:textColorPrimaryInverse">#295055</item>
    <item name="android:textColorSecondaryInverse">#295055</item>
    <item name="android:textColorTertiaryInverse">#295055</item>

     <item name="android:windowBackground">@drawable/custom_background</item>        
</style>

<!-- Application theme. -->
<style name="AppTheme" parent="AppBaseTheme">
    <!-- All customizations that are NOT specific to a particular API-level can go here. -->
</style>

parent="@android:style/Theme.Light" is Google’s native colors. Here is a reference of what the native styles are: https://android.googlesource.com/platform/frameworks/base/+/refs/heads/master/core/res/res/values/themes.xml

The default Android style is also called “Theme”. So you calling it Theme probably confused the program.

name="Theme.AppBaseTheme" means that you are creating a style that inherits all the styles from parent="@android:style/Theme.Light". This part you can ignore unless you want to inherit from AppBaseTheme again. = <style name="AppTheme" parent="AppBaseTheme">

@drawable/custom_background is a custom image I put in the drawable’s folder. It is a 300x300 png image.

#295055 is a dark blue color.

My code changes the background and text color. For Button text, please look through Google’s native stlyes (the link I gave u above).

Then in Android Manifest, remember to include the code:

<application
android:theme="@style/Theme.AppBaseTheme">

Python creating a dictionary of lists

easy way is:

a = [1,2]
d = {}
for i in a:
  d[i]=[i, ]

print(d)
{'1': [1, ], '2':[2, ]}

Selecting multiple columns with linq query and lambda expression

        Object AccountObject = _dbContext.Accounts
                                   .Join(_dbContext.Users, acc => acc.AccountId, usr => usr.AccountId, (acc, usr) => new { acc, usr })
                                   .Where(x => x.usr.EmailAddress == key1)
                                   .Where(x => x.usr.Hash == key2)
                                   .Select(x => new { AccountId = x.acc.AccountId, Name = x.acc.Name })
                                   .SingleOrDefault();

When is the init() function run?

Something to add to this (which I would've added as a comment but the time of writing this post I'd not yet enough reputation)

Having multiple inits in the same package I've not yet found any guaranteed way to know what order in which they will be run. For example I have:

package config
    - config.go
    - router.go

Both config.go and router.go contain init() functions, but when running router.go's function ran first (which caused my app to panic).

If you're in a situation where you have multiple files, each with its own init() function be very aware that you aren't guaranteed to get one before the other. It is better to use a variable assignment as OneToOne shows in his example. Best part is: This variable declaration will happen before ALL init() functions in the package.

For example

config.go:

var ConfigSuccess = configureApplication()

func init() {
    doSomething()
}

func configureApplication() bool {
    l4g.Info("Configuring application...")
    if valid := loadCommandLineFlags(); !valid {
        l4g.Critical("Failed to load Command Line Flags")
        return false
    }
    return true
}

router.go:

func init() {
    var (
        rwd string
        tmp string
        ok  bool
    )
    if metapath, ok := Config["fs"]["metapath"].(string); ok {
        var err error
        Conn, err = services.NewConnection(metapath + "/metadata.db")
        if err != nil {
            panic(err)
        }
    }
}

regardless of whether var ConfigSuccess = configureApplication() exists in router.go or config.go, it will be run before EITHER init() is run.

How to check the first character in a string in Bash or UNIX shell?

Many ways to do this. You could use wildcards in double brackets:

str="/some/directory/file"
if [[ $str == /* ]]; then echo 1; else echo 0; fi

You can use substring expansion:

if [[ ${str:0:1} == "/" ]] ; then echo 1; else echo 0; fi

Or a regex:

if [[ $str =~ ^/ ]]; then echo 1; else echo 0; fi

Android: how to handle button click

#1 I use the last one frequently when having buttons on the layout which are not generated (but static obviously).

If you use it in practice and in a business application, pay extra attention here, because when you use source obfuscater like ProGuard, you'll need to mark these methods in your activity as to not be obfuscated.

For archiving some kind of compile-time-security with this approach, have a look at Android Lint (example).


#2 Pros and cons for all methods are almost the same and the lesson should be:

Use what ever is most appropriate or feels most intuitive to you.

If you have to assign the same OnClickListener to multiple button instances, save it in the class-scope (#1). If you need a simple listener for a Button, make an anonymous implementation:

button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        // Take action.
    }
});

I tend to not implement the OnClickListener in the activity, this gets a little confusing from time to time (especially when you implement multiple other event-handlers and nobody knows what this is all doing).

Does Spring @Transactional attribute work on a private method?

Same way as @loonis suggested to use TransactionTemplate one may use this helper component (Kotlin):

@Component
class TransactionalUtils {
    /**
     * Execute any [block] of code (even private methods)
     * as if it was effectively [Transactional]
     */
    @Transactional
    fun <R> executeAsTransactional(block: () -> R): R {
        return block()
    }
}

Usage:

@Service
class SomeService(private val transactionalUtils: TransactionalUtils) {

    fun foo() {
        transactionalUtils.executeAsTransactional { transactionalFoo() }
    }

    private fun transactionalFoo() {
        println("This method is executed within transaction")
    }
}

Don't know whether TransactionTemplate reuse existing transaction or not but this code definitely do.

How to validate an email address in PHP

I think you might be better off using PHP's inbuilt filters - in this particular case:

It can return a true or false when supplied with the FILTER_VALIDATE_EMAIL param.

Is there an SQLite equivalent to MySQL's DESCRIBE [table]?

The SQLite command line utility has a .schema TABLENAME command that shows you the create statements.

What is 'Currying'?

A curried function is applied to multiple argument lists, instead of just one.

Here is a regular, non-curried function, which adds two Int parameters, x and y:

scala> def plainOldSum(x: Int, y: Int) = x + y
plainOldSum: (x: Int,y: Int)Int
scala> plainOldSum(1, 2)
res4: Int = 3

Here is similar function that’s curried. Instead of one list of two Int parameters, you apply this function to two lists of one Int parameter each:

scala> def curriedSum(x: Int)(y: Int) = x + y
curriedSum: (x: Int)(y: Int)Intscala> second(2)
res6: Int = 3
scala> curriedSum(1)(2)
res5: Int = 3

What’s happening here is that when you invoke curriedSum, you actually get two traditional function invocations back to back. The first function invocation takes a single Int parameter named x , and returns a function value for the second function. This second function takes the Int parameter y.

Here’s a function named first that does in spirit what the first traditional function invocation of curriedSum would do:

scala> def first(x: Int) = (y: Int) => x + y
first: (x: Int)(Int) => Int

Applying 1 to the first function—in other words, invoking the first function and passing in 1 —yields the second function:

scala> val second = first(1)
second: (Int) => Int = <function1>

Applying 2 to the second function yields the result:

scala> second(2)
res6: Int = 3

How to convert an entire MySQL database characterset and collation to UTF-8?

To change the character set encoding to UTF-8 for the database itself, type the following command at the mysql> prompt. Replace DBNAME with the database name:

ALTER DATABASE DBNAME CHARACTER SET utf8 COLLATE utf8_general_ci;

How to implement a lock in JavaScript

I've had success mutex-promise.

I agree with other answers that you might not need locking in your case. But it's not true that one never needs locking in Javascript. You need mutual exclusivity when accessing external resources that do not handle concurrency.

How to escape JSON string?

I use System.Web.HttpUtility.JavaScriptStringEncode

string quoted = HttpUtility.JavaScriptStringEncode(input);

How to generate graphs and charts from mysql database in php

I use highcharts. They are very interactive (and very fancy I might add). You do have to get a little creative to access data from MySQL database, but if you have a general understanding of JavaScript and PHP, you should have no problems.

Best Practices for securing a REST API / web service

OWASP(Open Web Application Security Project) has some cheat sheets covering about all aspects of Web Application development. This Project is a very valuable and reliable source of information. Regarding REST services you can check this: https://www.owasp.org/index.php/REST_Security_Cheat_Sheet

Serializing PHP object to JSON

Try using this, this worked fine for me.

json_encode(unserialize(serialize($array)));

How to play .mp4 video in videoview in android?

Finally it works for me.

private VideoView videoView;

videoView = (VideoView) findViewById(R.id.videoView);

Uri video = Uri.parse("http://www.servername.com/projects/projectname/videos/1361439400.mp4");
videoView.setVideoURI(video);
videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
  @Override       
  public void onPrepared(MediaPlayer mp) {
       mp.setLooping(true);
       videoView.start();
    }
});

Hope this would help others.

test if event handler is bound to an element in jQuery

This works for me: $('#profile1').attr('onclick')

Extract column values of Dataframe as List in Apache Spark

An updated solution that gets you a list:

dataFrame.select("YOUR_COLUMN_NAME").map(r => r.getString(0)).collect.toList

How can I get the application's path in a .NET console application?

There are many ways to get executable path, which one we should use it depends on our needs here is a link which discuss different methods.

Different ways to get Application Executable Path

Programmatically read from STDIN or input file in Perl

Here is how I made a script that could take either command line inputs or have a text file redirected.

if ($#ARGV < 1) {
    @ARGV = ();
    @ARGV = <>;
    chomp(@ARGV);
}


This will reassign the contents of the file to @ARGV, from there you just process @ARGV as if someone was including command line options.

WARNING

If no file is redirected, the program will sit their idle because it is waiting for input from STDIN.

I have not figured out a way to detect if a file is being redirected in yet to eliminate the STDIN issue.

How to redirect 404 errors to a page in ExpressJS?

The 404 page should be set up just before the call to app.listen.Express has support for * in route paths. This is a special character which matches anything. This can be used to create a route handler that matches all requests.

app.get('*', (req, res) => {
  res.render('404', {
    title: '404',
    name: 'test',
    errorMessage: 'Page not found.'
  })
})

How to move columns in a MySQL table?

phpMyAdmin provides a GUI for this within the structure view of a table. Check to select the column you want to move and click the change action at the bottom of the column list. You can then change all of the column properties and you'll find the 'move column' function at the far right of the screen.

Of course this is all just building the queries in the perfectly good top answer but GUI fans might appreciate the alternative.

my phpMyAdmin version is 4.1.7

How do I copy the contents of one stream to another?

The following code to solve the issue copy the Stream to MemoryStream using CopyTo

Stream stream = new MemoryStream();

//any function require input the stream. In mycase to save the PDF file as stream document.Save(stream);

MemoryStream newMs = (MemoryStream)stream;

byte[] getByte = newMs.ToArray();

//Note - please dispose the stream in the finally block instead of inside using block as it will throw an error 'Access denied as the stream is closed'

How to import a csv file using python with headers intact, where first column is a non-numerical

You can use pandas library and reference the rows and columns like this:

import pandas as pd

input = pd.read_csv("path_to_file");

#for accessing ith row:
input.iloc[i]

#for accessing column named X
input.X

#for accessing ith row and column named X
input.iloc[i].X

Upgrading Node.js to latest version

Following Upgrading Node.js to latest version

sudo npm cache clean -f
sudo npm install -g n
sudo n stable

sudo ln -sf /usr/local/n/versions/node/<VERSION>/bin/node /usr/bin/node

For Upgrading Node.js to latest version

sudo n latest

If you need to do Undo then follow command

sudo apt-get install --reinstall nodejs-legacy     # fix /usr/bin/node
sudo n rm 6.0.0     # replace number with version of Node that was installed
sudo npm uninstall -g n

This method of upgrading node is now unstable and should not be used. The best way to manage Node.js versions is to use NVM: Node Version Management.!

Installation

You can read the installation steps on the nvm [GitHub page][1]. There are only two easy steps for installation and configuration. Using nvm

If you work with a lot of different Node.js utilities, you know that sometimes you need to quickly switch to other versions of Node.js without hosing your entire machine. That's where you can use nvm to download, install, and use different versions of Node.js:

nvm install 4.0

At any given time you can switch to another with use:

nvm use 0.12

Javascript Get Element by Id and set the value

If myFunc(variable) is executed before textarea is rendered to page, you will get the null exception error.

<html>
    <head>
    <title>index</title>
    <script type="text/javascript">
        function myFunc(variable){
            var s = document.getElementById(variable);
            s.value = "new value";
        }   
        myFunc("id1");
    </script>
    </head>
    <body>
        <textarea id="id1"></textarea>
    </body>
</html>
//Error message: Cannot set property 'value' of null 

So, make sure your textarea does exist in the page, and then call myFunc, you can use window.onload or $(document).ready function. Hope it's helpful.

What does "res.render" do, and what does the html file look like?

What does res.render do and what does the html file look like?

res.render() function compiles your template (please don't use ejs), inserts locals there, and creates html output out of those two things.


Answering Edit 2 part.

// here you set that all templates are located in `/views` directory
app.set('views', __dirname + '/views');

// here you set that you're using `ejs` template engine, and the
// default extension is `ejs`
app.set('view engine', 'ejs');

// here you render `orders` template
response.render("orders", {orders: orders_json});

So, the template path is views/ (first part) + orders (second part) + .ejs (third part) === views/orders.ejs


Anyway, express.js documentation is good for what it does. It is API reference, not a "how to use node.js" book.

Removing the remembered login and password list in SQL Server Management Studio

In my scenario I only wanted to remove a specific username/password from the list which had many other saved connections I didn't want to forget. It turns out the SqlStudio.bin file others are discussing here is a .NET binary serialization of the Microsoft.SqlServer.Management.UserSettings.SqlStudio class, which can be deserialized, modified and reserialized to modify specific settings.

To accomplish removal of the specific login, I created a new C# .Net 4.6.1 console application and added a reference to the namespace which is located in the following dll: C:\Program Files (x86)\Microsoft SQL Server\130\Tools\Binn\ManagementStudio\Microsoft.SqlServer.Management.UserSettings.dll (your path may differ slightly depending on SSMS version)

From there I could easily create and modify the settings as desired:

using System.IO;
using System.Runtime.Serialization.Formatters.Binary;
using Microsoft.SqlServer.Management.UserSettings;

class Program
{
    static void Main(string[] args)
    {
        var settingsFile = new FileInfo(@"C:\Users\%username%\AppData\Roaming\Microsoft\SQL Server Management Studio\13.0\SqlStudio.bin");

        // Backup our original file just in case...
        File.Copy(settingsFile.FullName, settingsFile.FullName + ".backup");

        BinaryFormatter fmt = new BinaryFormatter();

        SqlStudio settings = null;

        using(var fs = settingsFile.Open(FileMode.Open))
        {
            settings = (SqlStudio)fmt.Deserialize(fs);
        }

        // The structure of server types / servers / connections requires us to loop
        // through multiple nested collections to find the connection to be removed.
        // We start here with the server types

        var serverTypes = settings.SSMS.ConnectionOptions.ServerTypes;

        foreach (var serverType in serverTypes)
        {
            foreach (var server in serverType.Value.Servers)
            {
                // Will store the connection for the provided server which should be removed
                ServerConnectionSettings removeConn = null;

                foreach (var conn in server.Connections)
                {
                    if (conn.UserName == "adminUserThatShouldBeRemoved")
                    {
                        removeConn = conn;
                        break;
                    }
                }

                if (removeConn != null)
                {
                    server.Connections.RemoveItem(removeConn);
                }
            }
        }

        using (var fs = settingsFile.Open(FileMode.Create))
        {
            fmt.Serialize(fs, settings);
        }
    }
}

Windows batch: sleep

To wait 10 seconds:

choice /T 10 /C X /D X /N

Viewing all `git diffs` with vimdiff

git config --global diff.tool vimdiff
git config --global difftool.prompt false

Typing git difftool yields the expected behavior.

Navigation commands,

  • :qa in vim cycles to the next file in the changeset without saving anything.

Aliasing (example)

git config --global alias.d difftool

.. will let you type git d to invoke vimdiff.

Advanced use-cases,

  • By default, git calls vimdiff with the -R option. You can override it with git config --global difftool.vimdiff.cmd 'vimdiff "$LOCAL" "$REMOTE"'. That will open vimdiff in writeable mode which allows edits while diffing.
  • :wq in vim cycles to the next file in the changeset with changes saved.

How can I show three columns per row?

Even though the above answer appears to be correct, I wanted to add a (hopefully) more readable example that also stays in 3 columns form at different widths:

_x000D_
_x000D_
.flex-row-container {_x000D_
    background: #aaa;_x000D_
    display: flex;_x000D_
    flex-wrap: wrap;_x000D_
    align-items: center;_x000D_
    justify-content: center;_x000D_
}_x000D_
.flex-row-container > .flex-row-item {_x000D_
    flex: 1 1 30%; /*grow | shrink | basis */_x000D_
    height: 100px;_x000D_
}_x000D_
_x000D_
.flex-row-item {_x000D_
  background-color: #fff4e6;_x000D_
  border: 1px solid #f76707;_x000D_
}
_x000D_
<div class="flex-row-container">_x000D_
  <div class="flex-row-item">1</div>_x000D_
  <div class="flex-row-item">2</div>_x000D_
  <div class="flex-row-item">3</div>_x000D_
  <div class="flex-row-item">4</div>_x000D_
  <div class="flex-row-item">5</div>_x000D_
  <div class="flex-row-item">6</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Hope this helps someone else.

Simple PHP form: Attachment to email (code golf)

A combination of this http://www.webcheatsheet.com/PHP/send_email_text_html_attachment.php#attachment

with the php upload file example would work. In the upload file example instead of using move_uploaded_file to move it from the temporary folder you would just open it:

$attachment = chunk_split(base64_encode(file_get_contents($tmp_file))); 

where $tmp_file = $_FILES['userfile']['tmp_name'];

and send it as an attachment like the rest of the example.

All in one file / self contained:

<? if(isset($_POST['submit'])){
//process and email
}else{
//display form
}
?>

I think its a quick exercise to get what you need working based on the above two available examples.

P.S. It needs to get uploaded somewhere before Apache passes it along to PHP to do what it wants with it. That would be your system's temp folder by default unless it was changed in the config file.

How does one capture a Mac's command key via JavaScript?

EDIT: As of 2019, e.metaKey is supported on all major browsers as per the MDN.

Note that on Windows, although the ? Windows key is considered to be the "meta" key, it is not going to be captured by browsers as such.

This is only for the command key on MacOS/keyboards.


Unlike Shift/Alt/Ctrl, the Cmd (“Apple”) key is not considered a modifier key—instead, you should listen on keydown/keyup and record when a key is pressed and then depressed based on event.keyCode.

Unfortunately, these key codes are browser-dependent:

  • Firefox: 224
  • Opera: 17
  • WebKit browsers (Safari/Chrome): 91 (Left Command) or 93 (Right Command)

You might be interested in reading the article JavaScript Madness: Keyboard Events, from which I learned that knowledge.

Is it possible to display inline images from html in an Android TextView?

This is what I use, which does not need you to hardcore your resource names and will look for the drawable resources first in your apps resources and then in the stock android resources if nothing was found - allowing you to use default icons and such.

private class ImageGetter implements Html.ImageGetter {

     public Drawable getDrawable(String source) {
        int id;

        id = getResources().getIdentifier(source, "drawable", getPackageName());

        if (id == 0) {
            // the drawable resource wasn't found in our package, maybe it is a stock android drawable?
            id = getResources().getIdentifier(source, "drawable", "android");
        }

        if (id == 0) {
            // prevent a crash if the resource still can't be found
            return null;    
        }
        else {
            Drawable d = getResources().getDrawable(id);
            d.setBounds(0,0,d.getIntrinsicWidth(),d.getIntrinsicHeight());
            return d;
        }
     }

 }

Which can be used as such (example):

String myHtml = "This will display an image to the right <img src='ic_menu_more' />";
myTextview.setText(Html.fromHtml(myHtml, new ImageGetter(), null);

how to make jni.h be found?

I don't know if this applies in this case, but sometimes the file got deleted for unknown reasons, copying it again into the respective folder should resolve the problem.

Android open camera from button

you can use the following code

         Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);

                pic = new File(Environment.getExternalStorageDirectory(),
                        mApp.getPreference().getString(Common.u_id, "") + ".jpg");

                picUri = Uri.fromFile(pic);

                cameraIntent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, picUri);

                cameraIntent.putExtra("return-data", true);
                startActivityForResult(cameraIntent, PHOTO);

What causes a TCP/IP reset (RST) flag to be sent?

Run a packet sniffer (e.g., Wireshark) also on the peer to see whether it's the peer who's sending the RST or someone in the middle.

mysql error 1364 Field doesn't have a default values

Before every insert action I added below line and solved my issue,

SET SQL_MODE = '';

I'm not sure if this is the best solution,

SET SQL_MODE = ''; INSERT INTO  `mytable` (  `field1` ,  `field2`) VALUES ('value1',  'value2');

Find size of object instance in bytes in c#

First of all, a warning: what follows is strictly in the realm of ugly, undocumented hacks. Do not rely on this working - even if it works for you now, it may stop working tomorrow, with any minor or major .NET update.

You can use the information in this article on CLR internals MSDN Magazine Issue 2005 May - Drill Into .NET Framework Internals to See How the CLR Creates Runtime Objects - last I checked, it was still applicable. Here's how this is done (it retrieves the internal "Basic Instance Size" field via TypeHandle of the type).

object obj = new List<int>(); // whatever you want to get the size of
RuntimeTypeHandle th = obj.GetType().TypeHandle;
int size = *(*(int**)&th + 1);
Console.WriteLine(size);

This works on 3.5 SP1 32-bit. I'm not sure if field sizes are the same on 64-bit - you might have to adjust the types and/or offsets if they are not.

This will work for all "normal" types, for which all instances have the same, well-defined types. Those for which this isn't true are arrays and strings for sure, and I believe also StringBuilder. For them you'll have add the size of all contained elements to their base instance size.

How do I assert my exception message with JUnit Test annotation?

Import the catch-exception library, and use that. It's much cleaner than the ExpectedException rule or a try-catch.

Example form their docs:

import static com.googlecode.catchexception.CatchException.*;
import static com.googlecode.catchexception.apis.CatchExceptionHamcrestMatchers.*;

// given: an empty list
List myList = new ArrayList();

// when: we try to get the first element of the list
catchException(myList).get(1);

// then: we expect an IndexOutOfBoundsException with message "Index: 1, Size: 0"
assertThat(caughtException(),
  allOf(
    instanceOf(IndexOutOfBoundsException.class),
    hasMessage("Index: 1, Size: 0"),
    hasNoCause()
  )
);

How do I run a Python program?

if you dont want call filename.py you can add .PY to the PATHEXT, that way you will just call filename

Determine if 2 lists have the same elements, regardless of order?

Determine if 2 lists have the same elements, regardless of order?

Inferring from your example:

x = ['a', 'b']
y = ['b', 'a']

that the elements of the lists won't be repeated (they are unique) as well as hashable (which strings and other certain immutable python objects are), the most direct and computationally efficient answer uses Python's builtin sets, (which are semantically like mathematical sets you may have learned about in school).

set(x) == set(y) # prefer this if elements are hashable

In the case that the elements are hashable, but non-unique, the collections.Counter also works semantically as a multiset, but it is far slower:

from collections import Counter
Counter(x) == Counter(y)

Prefer to use sorted:

sorted(x) == sorted(y) 

if the elements are orderable. This would account for non-unique or non-hashable circumstances, but this could be much slower than using sets.

Empirical Experiment

An empirical experiment concludes that one should prefer set, then sorted. Only opt for Counter if you need other things like counts or further usage as a multiset.

First setup:

import timeit
import random
from collections import Counter

data = [str(random.randint(0, 100000)) for i in xrange(100)]
data2 = data[:]     # copy the list into a new one

def sets_equal(): 
    return set(data) == set(data2)

def counters_equal(): 
    return Counter(data) == Counter(data2)

def sorted_lists_equal(): 
    return sorted(data) == sorted(data2)

And testing:

>>> min(timeit.repeat(sets_equal))
13.976069927215576
>>> min(timeit.repeat(counters_equal))
73.17287588119507
>>> min(timeit.repeat(sorted_lists_equal))
36.177085876464844

So we see that comparing sets is the fastest solution, and comparing sorted lists is second fastest.

How can I order a List<string>?

You can use Sort

List<string> ListaServizi = new List<string>() { };
ListaServizi.Sort();

.htaccess rewrite subdomain to directory

Try putting this in your .htaccess file:

RewriteEngine on
RewriteCond %{HTTP_HOST} ^sub.domain.com
RewriteRule ^(.*)$ /subdomains/sub/$1 [L,NC,QSA]

For a more general rule (that works with any subdomain, not just sub) replace the last two lines with this:

RewriteEngine on
RewriteCond %{HTTP_HOST} ^(.*)\.domain\.com
RewriteRule ^(.*)$ subdomains/%1/$1 [L,NC,QSA]

Error after upgrading pip: cannot import name 'main'

The commands above didn't work for me but those were very helpful:

sudo apt purge python3-pip
sudo rm -rf '/usr/lib/python3/dist-packages/pip'  
sudo apt install python3-pip
cd
cd .local/lib/python3/site-packages
sudo rm -rf pip*  
cd
cd .local/lib/python3.5/site-packages
sudo rm -rf pip*  
sudo pip3 install jupyter

Change directory in PowerShell

Set-Location -Path 'Q:\MyDir'

In PowerShell cd = Set-Location

"configuration file /etc/nginx/nginx.conf test failed": How do I know why this happened?

If you want to check syntax error for any nginx files, you can use the -c option.

[root@server ~]# sudo nginx -t -c /etc/nginx/my-server.conf
nginx: the configuration file /etc/nginx/my-server.conf syntax is ok
nginx: configuration file /etc/nginx/my-server.conf test is successful
[root@server ~]# 

What does 'synchronized' mean?

synchronized simple means no two threads can access the block/method simultaneously. When we say any block/method of a class is synchronized it means only one thread can access them at a time. Internally the thread which tries to access it first take a lock on that object and as long as this lock is not available no other thread can access any of the synchronized methods/blocks of that instance of the class.

Note another thread can access a method of the same object which is not defined to be synchronized. A thread can release the lock by calling

Object.wait()

How to initialize array to 0 in C?

If you'd like to initialize the array to values other than 0, with gcc you can do:

int array[1024] = { [ 0 ... 1023 ] = -1 };

This is a GNU extension of C99 Designated Initializers. In older GCC, you may need to use -std=gnu99 to compile your code.

Rails Root directory path?

In some cases you may want the Rails root without having to load Rails.

For example, you get a quicker feedback cycle when TDD'ing models that do not depend on Rails by requiring spec_helper instead of rails_helper.

# spec/spec_helper.rb

require 'pathname'

rails_root = Pathname.new('..').expand_path(File.dirname(__FILE__))

[
  rails_root.join('app', 'models'),
  # Add your decorators, services, etc.
].each do |path|
  $LOAD_PATH.unshift path.to_s
end

Which allows you to easily load Plain Old Ruby Objects from their spec files.

# spec/models/poro_spec.rb

require 'spec_helper'

require 'poro'

RSpec.describe ...

Changing ViewPager to enable infinite page scrolling

Actually, I've been looking at the various ways to do this "infinite" pagination, and even though the human notion of time is that it is infinite (even though we have a notion of the beginning and end of time), computers deal in the discrete. There is a minimum and maximum time (that can be adjusted as time goes on, remember the basis of the Y2K scare?).

Anyways, the point of this discussion is that it is/should be sufficient to support a relatively infinite date range through an actually finite date range. A great example of this is the Android framework's CalendarView implementation, and the WeeksAdapter within it. The default minimum date is in 1900 and the default maximum date is in 2100, this should cover 99% of the calendar use of anyone within a 10 year radius around today easily.

What they do in their implementation (focused on weeks) is compute the number of weeks between the minimum and maximum date. This becomes the number of pages in the pager. Remember that the pager doesn't need to maintain all of these pages simultaneously (setOffscreenPageLimit(int)), it just needs to be able to create the page based on the page number (or index/position). In this case the index is the number of weeks that the week is from the minimum date. With this approach you just have to maintain the minimum date and the number of pages (distance to the maximum date), then for any page you can easily compute the week associated with that page. No dancing around the fact that ViewPager doesn't support looping (a.k.a infinite pagination), and trying to force it to behave like it can scroll infinitely.

new FragmentStatePagerAdapter(getFragmentManager()) {
    @Override
    public Fragment getItem(int index) {
        final Bundle arguments = new Bundle(getArguments());
        final Calendar temp_calendar = Calendar.getInstance();
        temp_calendar.setTimeInMillis(_minimum_date.getTimeInMillis());
        temp_calendar.setFirstDayOfWeek(_calendar.getStartOfWeek());
        temp_calendar.add(Calendar.WEEK_OF_YEAR, index);
        // Moves to the first day of this week
        temp_calendar.add(Calendar.DAY_OF_YEAR,
                -UiUtils.modulus(temp_calendar.get(Calendar.DAY_OF_WEEK) - temp_calendar.getFirstDayOfWeek(),
                7));
        arguments.putLong(KEY_DATE, temp_calendar.getTimeInMillis());
        return Fragment.instantiate(getActivity(), WeekDaysFragment.class.getName(), arguments);
    }

    @Override
    public int getCount() {
        return _total_number_of_weeks;
    }
};

Then WeekDaysFragment can easily display the week starting at the date passed in its arguments.

Alternatively, it seems that some version of the Calendar app on Android uses a ViewSwitcher (which means there's only 2 pages, the one you see and the hidden page). It then changes the transition animation based on which way the user swiped and renders the next/previous page accordingly. In this way you get infinite pagination because it just switching between two pages infinitely. This requires using a View for the page though, which is way I went with the first approach.

In general, if you want "infinite pagination", it's probably because your pages are based off of dates or times somehow. If this is the case consider using a finite subset of time that is relatively infinite instead. This is how CalendarView is implemented for example. Or you can use the ViewSwitcher approach. The advantage of these two approaches is that neither does anything particularly unusual with the ViewSwitcher or ViewPager, and doesn't require any tricks or reimplementation to coerce them to behave infinitely (ViewSwitcher is already designed to switch between views infinitely, but ViewPager is designed to work on a finite, but not necessarily constant, set of pages).

Maven plugin in Eclipse - Settings.xml file is missing

Working on Mac I followed the answer of Sean Patrick Floyd placing a settings.xml like above in my user folder /Users/user/.m2/

But this did not help. So I opened a Terminal and did a ls -la on the folder. This was showing

-rw-r--r--@

thus staff and everone can at least read the file. So I wondered if the message isn't wrong and if the real cause is the lack of write permissions. I set the file to:

-rw-r--rw-@

This did it. The message disappeared.

How can I grep for a string that begins with a dash/hyphen?

grep "^-X" file

It will grep and pick all the lines form the file. ^ in the grep"^" indicates a line starting with

How can I get the current time in C#?

DateTime.Now.ToShortTimeString().ToString()

This Will give you DateTime as 10:50PM

How can I compare strings in C using a `switch` statement?

There is no way to do this in C. There are a lot of different approaches. Typically the simplest is to define a set of constants that represent your strings and do a look up by string on to get the constant:

#define BADKEY -1
#define A1 1
#define A2 2
#define B1 3
#define B2 4

typedef struct { char *key; int val; } t_symstruct;

static t_symstruct lookuptable[] = {
    { "A1", A1 }, { "A2", A2 }, { "B1", B1 }, { "B2", B2 }
};

#define NKEYS (sizeof(lookuptable)/sizeof(t_symstruct))

int keyfromstring(char *key)
{
    int i;
    for (i=0; i < NKEYS; i++) {
        t_symstruct *sym = lookuptable[i];
        if (strcmp(sym->key, key) == 0)
            return sym->val;
    }
    return BADKEY;
}

/* ... */
switch (keyfromstring(somestring)) {
case A1: /* ... */ break;
case A2: /* ... */ break;
case B1: /* ... */ break;
case B2: /* ... */ break;
case BADKEY: /* handle failed lookup */
}

There are, of course, more efficient ways to do this. If you keep your keys sorted, you can use a binary search. You could use a hashtable too. These things change your performance at the expense of maintenance.

File changed listener in Java

Spring Integration provides a nice mechanism for watching Directories and files: http://static.springsource.org/spring-integration/reference/htmlsingle/#files. Pretty sure it's cross platform (I've used it on mac, linux, and windows).

Python PDF library

Reportlab. There is an open source version, and a paid version which adds the Report Markup Language (an alternative method of defining your document).

Wait on the Database Engine recovery handle failed. Check the SQL server error log for potential causes

This post is high up when you google that error message, which I got when installing security patch KB4505224 on SQL Server 2017 Express i.e. None of the above worked for me, but did consume several hours trying.

The solution for me, partly from here was:

  1. uninstall SQL Server
  2. in Regional Settings / Management / System Locale, "Beta: UTF-8 support" should be OFF
  3. re-install SQL Server
  4. Let Windows install the patch.

And all was well.

More on this here.

libpthread.so.0: error adding symbols: DSO missing from command line

Please add: CFLAGS="-lrt" and LDFLAGS="-lrt"

Why does ANT tell me that JAVA_HOME is wrong when it is not?

In eclipse set the installed JRE setting to the JDK - in the project (project properties -> Java Build Path-> Libraries), or global default in preferences (Java->Installed JREs). The eclispe setting is stronger than the system variable.

Change value of input placeholder via model?

You can bind with a variable in the controller:

<input type="text" ng-model="inputText" placeholder="{{somePlaceholder}}" />

In the controller:

$scope.somePlaceholder = 'abc';

Redirecting to previous page after login? PHP

When user gets to the login page use this to see where is come from

$_SERVER['HTTP_REFERER']

Then set this value into the session, and when he is authenticated use url from the session to redirect him back. But you should do some checking before, if the url is your site. Maybe he come from another site directly to login :)

How to resolve this JNI error when trying to run LWJGL "Hello World"?

A CLASSPATH entry is either a directory at the head of a package hierarchy of .class files, or a .jar file. If you're expecting ./lib to include all the .jar files in that directory, it won't. You have to name them explicitly.

How do I kill a process using Vb.NET or C#?

You'll want to use the System.Diagnostics.Process.Kill method. You can obtain the process you want using System.Diagnostics.Proccess.GetProcessesByName.

Examples have already been posted here, but I found that the non-.exe version worked better, so something like:

foreach ( Process p in System.Diagnostics.Process.GetProcessesByName("winword") )
{
    try
    {
        p.Kill();
        p.WaitForExit(); // possibly with a timeout
    }
    catch ( Win32Exception winException )
    {
        // process was terminating or can't be terminated - deal with it
    }
    catch ( InvalidOperationException invalidException )
    {
        // process has already exited - might be able to let this one go
     }
}

You probably don't have to deal with NotSupportedException, which suggests that the process is remote.

How do you read CSS rule values with JavaScript?

const getStyle = query => [...document.querySelector(query).computedStyleMap().entries()].map(e=>(e[1]+=[],e)).map(e=>e.join`:`+';').join`\n`

In one line, prints out generated css for any query.

Adding <script> to WordPress in <head> element

In your theme's functions.php:

function my_custom_js() {
    echo '<script type="text/javascript" src="myscript.js"></script>';
}
// Add hook for admin <head></head>
add_action( 'admin_head', 'my_custom_js' );
// Add hook for front-end <head></head>
add_action( 'wp_head', 'my_custom_js' );

jQuery or Javascript - how to disable window scroll without overflow:hidden;

Following Glens idea, here it goes another possibility. It would allow you to scroll inside the div, but would prevent the body to scroll with it, when the div scroll ends. However, it seems to accumulate too many preventDefault if you scroll too much, and then it creates a lag if you want to scroll up. Does anybody have a suggestion to fix that?

    $(".scrollInsideThisDiv").bind("mouseover",function(){
       var bodyTop = document.body.scrollTop;
       $('body').on({
           'mousewheel': function(e) {
           if (document.body.scrollTop == bodyTop) return;
           e.preventDefault();
           e.stopPropagation();
           }
       });
    });
    $(".scrollInsideThisDiv").bind("mouseleave",function(){
          $('body').unbind("mousewheel");
    });

How to hide UINavigationBar 1px bottom line

Here's a very simple solution:

self.navigationController.navigationBar.clipsToBounds = YES;

Transpose a matrix in Python

Is there a prize for being lazy and using the transpose function of NumPy arrays? ;)

import numpy as np

a = np.array([(1,2,3), (4,5,6)])

b = a.transpose()

Docker: Container keeps on restarting again on again

In my case i removed

Restart=always

added

tty: true

And executed the below command to open shell (daemon process, because docker reads the compose file and stops the container once it reaches the last line of the file).

docker-compose up -d

error: ‘NULL’ was not declared in this scope

To complete the other answers: If you are using C++11, use nullptr, which is a keyword that means a void pointer pointing to null. (instead of NULL, which is not a pointer type)

How to avoid Sql Query Timeout

While I would be tempted to blame my issues - I'm getting the same error with my query, which is much, much bigger and involves a lot of loops - on the network, I think this is not the case.

Unfortunately it's not that simple. Query runs for 3+ hours before getting that error and apparently it crashes at the same time if it's just a query in SSMS and a job on SQL Server (did not look into details of that yet, so not sure if it's the same error; definitely same spot, though).

So just in case someone comes here with similar problem, this thread: https://www.sqlservercentral.com/Forums/569962/The-semaphore-timeout-period-has-expired

suggest that it may equally well be a hardware issue or actual timeout.

My loops aren't even (they depend on sales level in given month) in terms of time required for each, so good month takes about 20 mins to calculate (query looks at 4 years).

That way it's entirely possible I need to optimise my query. I would even say it's likely, as some changes I did included new tables, which are heaps... So another round of indexing my data before tearing into VM config and hardware tests.

Being aware that this is old question: I'm on SQL Server 2012 SE, SSMS is 2018 Beta and VM the SQL Server runs on has exclusive use of 132GB of RAM (30% total), 8 cores, and 2TB of SSD SAN.

Dictionary with list of strings as value

A simpler way of doing it is:

var dictionary = list.GroupBy(it => it.Key).ToDictionary(dict => dict.Key, dict => dict.Select(item => item.value).ToList());

How do you resize a form to fit its content automatically?

By using the various sizing properties (Dock, Anchor) or container controls (Panel, TableLayoutPanel, FlowLayoutPanel, etc.) you can only dictate the size from the outer control down to the inner controls. But there is nothing (working) within the .Net framework that allows to dictate the size of a container through the size of the child control. I also missed this a few times and tried the AutoSize property, but it never worked.

So all you can do is trying to get this stuff done manually, sorry.

Swift - Remove " character from string

Swift 3 and Swift 4:

text2 = text2.textureName.replacingOccurrences(of: "\"", with: "", options: NSString.CompareOptions.literal, range:nil)

Latest documents updated to Swift 3.0.1 have:

  • Null Character (\0)
  • Backslash (\\)
  • Horizontal Tab (\t)
  • Line Feed (\n)
  • Carriage Return (\r)
  • Double Quote (\")
  • Single Quote (\')
  • Unicode scalar (\u{n}), where n is between one and eight hexadecimal digits

If you need more details you can take a look to the official docs here

Is there a developers api for craigslist.org

Good news everybody! Craigslist has actually released a bulk posting api now!

Enjoy

Select default option value from typescript angular 6

I had similar issues with Angular6 . After going through many posts. I had to import FormsModule as below in app.module.ts .

import {FormsModule} from '@angular/forms';

Then my ngModel tag worked . Please try this.

<select [(ngModel)]='nrSelect' class='form-control'>                                                                
                                <option [ngValue]='47'>47</option>
                                    <option [ngValue]='46'>46</option>
                                    <option [ngValue]='45'>45</option>
</select>

How to get rid of blank pages in PDF exported from SSRS

Have you tried to see if there is any white space on the right of your report? If so you can drag it back to the end of your report and then drag the report background back to the same spot.

TSQL How do you output PRINT in a user defined function?

No, sorry. User-defined functions in SQL Server are really limited, because of a requirement that they be deterministic. No way round it, as far as I know.

Have you tried debugging the SQL code with Visual Studio?

Plot two histograms on single chart with matplotlib

The accepted answers gives the code for a histogram with overlapping bars, but in case you want each bar to be side-by-side (as I did), try the variation below:

import numpy as np
import matplotlib.pyplot as plt
plt.style.use('seaborn-deep')

x = np.random.normal(1, 2, 5000)
y = np.random.normal(-1, 3, 2000)
bins = np.linspace(-10, 10, 30)

plt.hist([x, y], bins, label=['x', 'y'])
plt.legend(loc='upper right')
plt.show()

enter image description here

Reference: http://matplotlib.org/examples/statistics/histogram_demo_multihist.html

EDIT [2018/03/16]: Updated to allow plotting of arrays of different sizes, as suggested by @stochastic_zeitgeist

How to convert int to NSString?

If this string is for presentation to the end user, you should use NSNumberFormatter. This will add thousands separators, and will honor the localization settings for the user:

NSInteger n = 10000;
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.numberStyle = NSNumberFormatterDecimalStyle;
NSString *string = [formatter stringFromNumber:@(n)];

In the US, for example, that would create a string 10,000, but in Germany, that would be 10.000.

How can I format a nullable DateTime with ToString()?

Console.WriteLine(dt2 != null ? dt2.Value.ToString("yyyy-MM-dd hh:mm:ss") : "n/a"); 

EDIT: As stated in other comments, check that there is a non-null value.

Update: as recommended in the comments, extension method:

public static string ToString(this DateTime? dt, string format)
    => dt == null ? "n/a" : ((DateTime)dt).ToString(format);

And starting in C# 6, you can use the null-conditional operator to simplify the code even more. The expression below will return null if the DateTime? is null.

dt2?.ToString("yyyy-MM-dd hh:mm:ss")

What is an alternative to execfile in Python 3?

Note that the above pattern will fail if you're using PEP-263 encoding declarations that aren't ascii or utf-8. You need to find the encoding of the data, and encode it correctly before handing it to exec().

class python3Execfile(object):
    def _get_file_encoding(self, filename):
        with open(filename, 'rb') as fp:
            try:
                return tokenize.detect_encoding(fp.readline)[0]
            except SyntaxError:
                return "utf-8"

    def my_execfile(filename):
        globals['__file__'] = filename
        with open(filename, 'r', encoding=self._get_file_encoding(filename)) as fp:
            contents = fp.read()
        if not contents.endswith("\n"):
            # http://bugs.python.org/issue10204
            contents += "\n"
        exec(contents, globals, globals)

Convert UIImage to NSData and convert back to UIImage in Swift?

Image to Data:-

    if let img = UIImage(named: "xxx.png") {
        let pngdata = img.pngData()
    }

   if let img = UIImage(named: "xxx.jpeg") {
        let jpegdata = img.jpegData(compressionQuality: 1)
    }

Data to Image:-

 let image = UIImage(data: pngData)

How To Get The Current Year Using Vba

Year(Date)

Year(): Returns the year portion of the date argument.
Date: Current date only.

Explanation of both of these functions from here.

Html.Textbox VS Html.TextboxFor

IMO the main difference is that Textbox is not strongly typed. TextboxFor take a lambda as a parameter that tell the helper the with element of the model to use in a typed view.

You can do the same things with both, but you should use typed views and TextboxFor when possible.

How do I install and use curl on Windows?

It's probably worth noting that Powershell v3 and up, contains a cmdlet called Invoke-WebRequest that has some curl-ish capabilities. The New-WebServiceProxy and Invoke-RestMethod cmdlets are probably worth mentioning too.

I'm not sure they will fit your needs or not, but although I'm not a Windows guy, I have to say I find the object approach PS takes, a lot easier to work with than utilities such as curl, wget etc. They may be worth taking a look at

Best way to incorporate Volley (or other library) into Android Studio project

For incorporate volley in android studio,

  1. paste the following command in terminal (
    git clone https://android.googlesource.com/platform/frameworks/volley ) and run it.

    Refer android developer tutorial for this.

    It will create a folder name volley in the src directory.
  2. Then go to android studio and right click on the project.
  3. choose New -> Module from the list.
  4. Then click on import existing Project from the below list.
  5. you will see a text input area namely source directory, browse the folder you downloaded (volley) and then click on finish.
  6. you will see a folder volley in your project view.
  7. the switch to android view and open the build:gradle(Module:app) file and append the following line in the dependency area:

    compile 'com.mcxiaoke.volley:library-aar:1.0.0'

  8. Now synchronise your project and also build your project.

Generic Interface

As an answer strictly in line with your question, I support cleytus's proposal.


You could also use a marker interface (with no method), say DistantCall, with several several sub-interfaces that have the precise signatures you want.

  • The general interface would serve to mark all of them, in case you want to write some generic code for all of them.
  • The number of specific interfaces can be reduced by using cleytus's generic signature.

Examples of 'reusable' interfaces:

    public interface DistantCall {
    }

    public interface TUDistantCall<T,U> extends DistantCall {
      T execute(U... us);
    }

    public interface UDistantCall<U> extends DistantCall {
      void execute(U... us);
    }

    public interface TDistantCall<T> extends DistantCall {
      T execute();
    }

    public interface TUVDistantCall<T, U, V> extends DistantCall {
      T execute(U u, V... vs);
    }
    ....

UPDATED in response to OP comment

I wasn't thinking of any instanceof in the calling. I was thinking your calling code knew what it was calling, and you just needed to assemble several distant call in a common interface for some generic code (for example, auditing all distant calls, for performance reasons). In your question, I have seen no mention that the calling code is generic :-(

If so, I suggest you have only one interface, only one signature. Having several would only bring more complexity, for nothing.

However, you need to ask yourself some broader questions :
how you will ensure that caller and callee do communicate correctly?

That could be a follow-up on this question, or a different question...

Java escape JSON String?

According to the answer here, quotes in values need to be escaped. You can do that with \"

So just repalce the quote in your values

msget = msget.replace("\"", "\\\"");

How to: Create trigger for auto update modified date with SQL Server 2008

My approach:

  • define a default constraint on the ModDate column with a value of GETDATE() - this handles the INSERT case

  • have a AFTER UPDATE trigger to update the ModDate column

Something like:

CREATE TRIGGER trg_UpdateTimeEntry
ON dbo.TimeEntry
AFTER UPDATE
AS
    UPDATE dbo.TimeEntry
    SET ModDate = GETDATE()
    WHERE ID IN (SELECT DISTINCT ID FROM Inserted)

Filter by process/PID in Wireshark

Just in case you are looking for an alternate way and the environment you use is Windows, Microsoft's Network Monitor 3.3 is a good choice. It has the process name column. You easily add it to a filter using the context menu and apply the filter.. As usual the GUI is very intuitive...

How to get text from EditText?

Put this in your MainActivity:

{
    public EditText bizname, storeno, rcpt, item, price, tax, total;
    public Button click, click2;
    int contentView;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.main_activity );
        bizname = (EditText) findViewById( R.id.editBizName );
        item = (EditText) findViewById( R.id.editItem );
        price = (EditText) findViewById( R.id.editPrice );
        tax = (EditText) findViewById( R.id.editTax );
        total = (EditText) findViewById( R.id.editTotal );
        click = (Button) findViewById( R.id.button );
    }
}

Put this under a button or something

public void clickBusiness(View view) {
    checkPermsOfStorage( this );

    bizname = (EditText) findViewById( R.id.editBizName );
    item = (EditText) findViewById( R.id.editItem );
    price = (EditText) findViewById( R.id.editPrice );
    tax = (EditText) findViewById( R.id.editTax );
    total = (EditText) findViewById( R.id.editTotal );
    String x = ("\nItem/Price: " + item.getText() + price.getText() + "\nTax/Total" + tax.getText() + total.getText());
    Toast.makeText( this, x, Toast.LENGTH_SHORT ).show();
    try {
        this.WriteBusiness(bizname,storeno,rcpt,item,price,tax,total);
        String vv = tax.getText().toString();
        System.console().printf( "%s", vv );
        //new XMLDivisionWriter(getString(R.string.SDDoc) + "/tax_div_business.xml");
    } catch (ReflectiveOperationException e) {
        e.printStackTrace();
    }
}

There! The debate is settled!

How to hide Table Row Overflow?

In general, if you are using white-space: nowrap; it is probably because you know which columns are going to contain content which wraps (or stretches the cell). For those columns, I generally wrap the cell's contents in a span with a specific class attribute and apply a specific width.

Example:

HTML:

<td><span class="description">My really long description</span></td>

CSS:

span.description {
    display: inline-block;
    overflow: hidden;
    white-space: nowrap;
    width: 150px;
}

How to upgrade Git to latest version on macOS?

I prefer not to alter the path hierarchy, but instead deal with git specifically...knowing that I'm never going to use old git to do what new git will now manage. This is a brute force solution.

NOTE: I installed XCode on Yosemite (10.10.2) clean first.

I then installed from the binary available on git-scm.com.

$ which git
/usr/bin/git
$ cd /usr/bin
$ sudo ln -sf /usr/local/git/bin/git
$ sudo ln -sf /usr/local/git/bin/git-credential-osxkeychain
$ sudo ln -sf /usr/local/git/bin/git-cvsserver
$ sudo ln -sf /usr/local/git/bin/git-receive-pack
$ sudo ln -sf /usr/local/git/bin/git-shell
$ sudo ln -sf /usr/local/git/bin/git-upload-archive
$ sudo ln -sf /usr/local/git/bin/git-upload-pack
$ ls -la
(you should see your new symlinks)

What is the function of the push / pop instructions used on registers in x86 assembly?

Pushing and popping registers are behind the scenes equivalent to this:

push reg   <= same as =>      sub  $8,%rsp        # subtract 8 from rsp
                              mov  reg,(%rsp)     # store, using rsp as the address

pop  reg    <= same as=>      mov  (%rsp),reg     # load, using rsp as the address
                              add  $8,%rsp        # add 8 to the rsp

Note this is x86-64 At&t syntax.

Used as a pair, this lets you save a register on the stack and restore it later. There are other uses, too.

How to get data from observable in angular2

this.myService.getConfig().subscribe(
  (res) => console.log(res),
  (err) => console.log(err),
  () => console.log('done!')
);

Is there a Python equivalent to Ruby's string interpolation?

Since Python 2.6.X you might want to use:

"my {0} string: {1}".format("cool", "Hello there!")

Set object property using reflection

Or you could wrap Marc's one liner inside your own extension class:

public static class PropertyExtension{       

   public static void SetPropertyValue(this object obj, string propName, object value)
    {
        obj.GetType().GetProperty(propName).SetValue(obj, value, null);
    }
}

and call it like this:

myObject.SetPropertyValue("myProperty", "myValue");

For good measure, let's add a method to get a property value:

public static object GetPropertyValue(this object obj, string propName)
{
        return obj.GetType().GetProperty(propName).GetValue (obj, null);
}

Get querystring from URL using jQuery

An easy way to do this with some jQuery and straight JavaScript, just view your console in Chrome or Firefox to see the output...

  var queries = {};
  $.each(document.location.search.substr(1).split('&'),function(c,q){
    var i = q.split('=');
    queries[i[0].toString()] = i[1].toString();
  });
  console.log(queries);

How to open a WPF Popup when another control is clicked, using XAML markup only?

The following approach is the same as Helge Klein's, except that the popup closes automatically when you click anywhere outside the Popup (including the ToggleButton itself):

<ToggleButton x:Name="Btn" IsHitTestVisible="{Binding ElementName=Popup, Path=IsOpen, Mode=OneWay, Converter={local:BoolInverter}}">
    <TextBlock Text="Click here for popup!"/>
</ToggleButton>

<Popup IsOpen="{Binding IsChecked, ElementName=Btn}" x:Name="Popup" StaysOpen="False">
    <Border BorderBrush="Black" BorderThickness="1" Background="LightYellow">
        <CheckBox Content="This is a popup"/>
    </Border>
</Popup>

"BoolInverter" is used in the IsHitTestVisible binding so that when you click the ToggleButton again, the popup closes:

public class BoolInverter : MarkupExtension, IValueConverter
{
    public override object ProvideValue(IServiceProvider serviceProvider)
    {
        return this;
    }

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is bool)
            return !(bool)value;
        return value;
    }
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return Convert(value, targetType, parameter, culture);
    }
}

...which shows the handy technique of combining IValueConverter and MarkupExtension in one.

I did discover one problem with this technique: WPF is buggy when two popups are on the screen at the same time. Specifically, if your toggle button is on the "overflow popup" in a toolbar, then there will be two popups open after you click it. You may then find that the second popup (your popup) will stay open when you click anywhere else on your window. At that point, closing the popup is difficult. The user cannot click the ToggleButton again to close the popup because IsHitTestVisible is false because the popup is open! In my app I had to use a few hacks to mitigate this problem, such as the following test on the main window, which says (in the voice of Louis Black) "if the popup is open and the user clicks somewhere outside the popup, close the friggin' popup.":

PreviewMouseDown += (s, e) =>
{
    if (Popup.IsOpen)
    {
        Point p = e.GetPosition(Popup.Child);
        if (!IsInRange(p.X, 0, ((FrameworkElement)Popup.Child).ActualWidth) ||
            !IsInRange(p.Y, 0, ((FrameworkElement)Popup.Child).ActualHeight))
            Popup.IsOpen = false;
    }
};
// Elsewhere...
public static bool IsInRange(int num, int lo, int hi) => 
    num >= lo && num <= hi;

How do I split a string into an array of characters?

You can split on an empty string:

var chars = "overpopulation".split('');

If you just want to access a string in an array-like fashion, you can do that without split:

var s = "overpopulation";
for (var i = 0; i < s.length; i++) {
    console.log(s.charAt(i));
}

You can also access each character with its index using normal array syntax. Note, however, that strings are immutable, which means you can't set the value of a character using this method, and that it isn't supported by IE7 (if that still matters to you).

var s = "overpopulation";

console.log(s[3]); // logs 'r'

What is polymorphism, what is it for, and how is it used?

Usually this refers the the ability for an object of type A to behave like an object of type B. In object oriented programming this is usually achieve by inheritance. Some wikipedia links to read more:

EDIT: fixed broken links.

How to compile and run C/C++ in a Unix console/Mac terminal?

Add following to get best warnings, you will not regret it. If you can, compile WISE (warning is error)

- Wall -pedantic -Weffc++ -Werror

Total number of items defined in an enum

You can use Enum.GetNames to return an IEnumerable of values in your enum and then .Count the resulting IEnumerable.

GetNames produces much the same result as GetValues but is faster.

How to store values from foreach loop into an array?

You can try to do my answer,

you wrote this:

<?php
foreach($group_membership as $i => $username) {
    $items = array($username);
}

print_r($items);
?>

And in your case I would do this:

<?php
$items = array();
foreach ($group_membership as $username) { // If you need the pointer (but I don't think) you have to add '$i => ' before $username
    $items[] = $username;
} ?>

As you show in your question it seems that you need an array of usernames that are in a particular group :) In this case I prefer a good sql query with a simple while loop ;)

<?php
$query = "SELECT `username` FROM group_membership AS gm LEFT JOIN users AS u ON gm.`idUser` = u.`idUser`";
$result = mysql_query($query);
while ($record = mysql_fetch_array($result)) { \
    $items[] = $username; 
} 
?>

while is faster, but the last example is only a result of an observation. :)

Sending a notification from a service in Android

@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
public void PushNotification()
{
    NotificationManager nm = (NotificationManager)context.getSystemService(NOTIFICATION_SERVICE);
    Notification.Builder builder = new Notification.Builder(context);
    Intent notificationIntent = new Intent(context, MainActivity.class);
    PendingIntent contentIntent = PendingIntent.getActivity(context,0,notificationIntent,0);

    //set
    builder.setContentIntent(contentIntent);
    builder.setSmallIcon(R.drawable.cal_icon);
    builder.setContentText("Contents");
    builder.setContentTitle("title");
    builder.setAutoCancel(true);
    builder.setDefaults(Notification.DEFAULT_ALL);

    Notification notification = builder.build();
    nm.notify((int)System.currentTimeMillis(),notification);
}

How can I add C++11 support to Code::Blocks compiler?

  1. Go to Toolbar -> Settings -> Compiler
  2. In the Selected compiler drop-down menu, make sure GNU GCC Compiler is selected
  3. Below that, select the compiler settings tab and then the compiler flags tab underneath
  4. In the list below, make sure the box for "Have g++ follow the C++11 ISO C++ language standard [-std=c++11]" is checked
  5. Click OK to save

How do I install PIL/Pillow for Python 3.6?

For python version 2.x you can simply use

  • pip install pillow

But for python version 3.X you need to specify

  • (sudo) pip3 install pillow

when you enter pip in bash hit tab and you will see what options you have

How can I get a file's size in C++?

How to use lseek/fseek/stat/fstat to get filesize ?

#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>


void
fseek_filesize(const char *filename)
{
    FILE *fp = NULL;
    long off;

    fp = fopen(filename, "r");
    if (fp == NULL)
    {
        printf("failed to fopen %s\n", filename);
        exit(EXIT_FAILURE);
    }

    if (fseek(fp, 0, SEEK_END) == -1)
    {
        printf("failed to fseek %s\n", filename);
        exit(EXIT_FAILURE);
    }

    off = ftell(fp);
    if (off == (long)-1)
    {
        printf("failed to ftell %s\n", filename);
        exit(EXIT_FAILURE);
    }

    printf("[*] fseek_filesize - file: %s, size: %ld\n", filename, off);

    if (fclose(fp) != 0)
    {
        printf("failed to fclose %s\n", filename);
        exit(EXIT_FAILURE);
    }
}

void
fstat_filesize(const char *filename)
{
    int fd;
    struct stat statbuf;

    fd = open(filename, O_RDONLY, S_IRUSR | S_IRGRP);
    if (fd == -1)
    {
        printf("failed to open %s\n", filename);
        exit(EXIT_FAILURE);
    }

    if (fstat(fd, &statbuf) == -1)
    {
        printf("failed to fstat %s\n", filename);
        exit(EXIT_FAILURE);
    }

    printf("[*] fstat_filesize - file: %s, size: %lld\n", filename, statbuf.st_size);

    if (close(fd) == -1)
    {
        printf("failed to fclose %s\n", filename);
        exit(EXIT_FAILURE);
    }
}

void
stat_filesize(const char *filename)
{
    struct stat statbuf;

    if (stat(filename, &statbuf) == -1)
    {
        printf("failed to stat %s\n", filename);
        exit(EXIT_FAILURE);
    }

    printf("[*] stat_filesize - file: %s, size: %lld\n", filename, statbuf.st_size);

}

void
seek_filesize(const char *filename)
{
    int fd;
    off_t off;

    if (filename == NULL)
    {
        printf("invalid filename\n");
        exit(EXIT_FAILURE);
    }

    fd = open(filename, O_RDONLY, S_IRUSR | S_IRGRP);
    if (fd == -1)
    {
        printf("failed to open %s\n", filename);
        exit(EXIT_FAILURE);
    }

    off = lseek(fd, 0, SEEK_END);
    if (off == (off_t)-1)
    {
        printf("failed to lseek %s\n", filename);
        exit(EXIT_FAILURE);
    }

    printf("[*] seek_filesize - file: %s, size: %lld\n", filename, off);

    if (close(fd) == -1)
    {
        printf("failed to close %s\n", filename);
        exit(EXIT_FAILURE);
    }
}

int
main(int argc, const char *argv[])
{
    int i;

    if (argc < 2)
    {
        printf("%s <file1> <file2>...\n", argv[0]);
        exit(0);
    }

    for(i = 1; i < argc; i++)
    {
        seek_filesize(argv[i]);
        stat_filesize(argv[i]);
        fstat_filesize(argv[i]);
        fseek_filesize(argv[i]);
    }

    return 0;
}

How to take the nth digit of a number in python

I would recommend adding a boolean check for the magnitude of the number. I'm converting a high milliseconds value to datetime. I have numbers from 2 to 200,000,200 so 0 is a valid output. The function as @Chris Mueller has it will return 0 even if number is smaller than 10**n.

def get_digit(number, n):
    return number // 10**n % 10

get_digit(4231, 5)
# 0

def get_digit(number, n):
    if number - 10**n < 0:
        return False
    return number // 10**n % 10

get_digit(4321, 5)
# False

You do have to be careful when checking the boolean state of this return value. To allow 0 as a valid return value, you cannot just use if get_digit:. You have to use if get_digit is False: to keep 0 from behaving as a false value.

AngularJS: Basic example to use authentication in Single Page Application

I've created a github repo summing up this article basically: https://medium.com/opinionated-angularjs/techniques-for-authentication-in-angularjs-applications-7bbf0346acec

ng-login Github repo

Plunker

I'll try to explain as good as possible, hope I help some of you out there:

(1) app.js: Creation of authentication constants on app definition

var loginApp = angular.module('loginApp', ['ui.router', 'ui.bootstrap'])
/*Constants regarding user login defined here*/
.constant('USER_ROLES', {
    all : '*',
    admin : 'admin',
    editor : 'editor',
    guest : 'guest'
}).constant('AUTH_EVENTS', {
    loginSuccess : 'auth-login-success',
    loginFailed : 'auth-login-failed',
    logoutSuccess : 'auth-logout-success',
    sessionTimeout : 'auth-session-timeout',
    notAuthenticated : 'auth-not-authenticated',
    notAuthorized : 'auth-not-authorized'
})

(2) Auth Service: All following functions are implemented in auth.js service. The $http service is used to communicate with the server for the authentication procedures. Also contains functions on authorization, that is if the user is allowed to perform a certain action.

angular.module('loginApp')
.factory('Auth', [ '$http', '$rootScope', '$window', 'Session', 'AUTH_EVENTS', 
function($http, $rootScope, $window, Session, AUTH_EVENTS) {

authService.login() = [...]
authService.isAuthenticated() = [...]
authService.isAuthorized() = [...]
authService.logout() = [...]

return authService;
} ]);

(3) Session: A singleton to keep user data. The implementation here depends on you.

angular.module('loginApp').service('Session', function($rootScope, USER_ROLES) {

    this.create = function(user) {
        this.user = user;
        this.userRole = user.userRole;
    };
    this.destroy = function() {
        this.user = null;
        this.userRole = null;
    };
    return this;
});

(4) Parent controller: Consider this as the "main" function of your application, all controllers inherit from this controller, and it's the backbone of the authentication of this app.

<body ng-controller="ParentController">
[...]
</body>

(5) Access control: To deny access on certain routes 2 steps have to be implemented:

a) Add data of the roles allowed to access each route, on ui router's $stateProvider service as can be seen below (same can work for ngRoute).

.config(function ($stateProvider, USER_ROLES) {
  $stateProvider.state('dashboard', {
    url: '/dashboard',
    templateUrl: 'dashboard/index.html',
    data: {
      authorizedRoles: [USER_ROLES.admin, USER_ROLES.editor]
    }
  });
})

b) On $rootScope.$on('$stateChangeStart') add the function to prevent state change if the user is not authorized.

$rootScope.$on('$stateChangeStart', function (event, next) {
    var authorizedRoles = next.data.authorizedRoles;
    if (!Auth.isAuthorized(authorizedRoles)) {
      event.preventDefault();
      if (Auth.isAuthenticated()) {
        // user is not allowed
        $rootScope.$broadcast(AUTH_EVENTS.notAuthorized);
      } else {
        // user is not logged in
        $rootScope.$broadcast(AUTH_EVENTS.notAuthenticated);
      }
    }
});

(6) Auth interceptor: This is implemented, but can't be checked on the scope of this code. After each $http request, this interceptor checks the status code, if one of the below is returned, then it broadcasts an event to force the user to log-in again.

angular.module('loginApp')
.factory('AuthInterceptor', [ '$rootScope', '$q', 'Session', 'AUTH_EVENTS',
function($rootScope, $q, Session, AUTH_EVENTS) {
    return {
        responseError : function(response) {
            $rootScope.$broadcast({
                401 : AUTH_EVENTS.notAuthenticated,
                403 : AUTH_EVENTS.notAuthorized,
                419 : AUTH_EVENTS.sessionTimeout,
                440 : AUTH_EVENTS.sessionTimeout
            }[response.status], response);
            return $q.reject(response);
        }
    };
} ]);

P.S. A bug with the form data autofill as stated on the 1st article can be easily avoided by adding the directive that is included in directives.js.

P.S.2 This code can be easily tweaked by the user, to allow different routes to be seen, or display content that was not meant to be displayed. The logic MUST be implemented server-side, this is just a way to show things properly on your ng-app.

SQL Server 2008 R2 can't connect to local database in Management Studio

Lots of the above helped for me, plus the accepted answer, but since I was on an EC2 instance, I had no idea what my instance name was. Finally, I opened SQLServer Configuration Manager and in the Name column, use whatever is there as your connection server, so in my case, .\EC2SQLEXPRESS and worked great!

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error: Libtool library used but 'LIBTOOL' is undefined

In my case on macOS I solved it with:

brew link libtool

Generating a UUID in Postgres for Insert statement?

Without extensions (cheat)

SELECT uuid_in(md5(random()::text || clock_timestamp()::text)::cstring);

output>> c2d29867-3d0b-d497-9191-18a9d8ee7830

(works at least in 8.4)

  • Thanks to @Erwin Brandstetter for clock_timestamp() explanation.

If you need a valid v4 UUID

SELECT uuid_in(overlay(overlay(md5(random()::text || ':' || clock_timestamp()::text) placing '4' from 13) placing to_hex(floor(random()*(11-8+1) + 8)::int)::text from 17)::cstring);

enter image description here * Thanks to @Denis Stafichuk @Karsten and @autronix


Also, in modern Postgres, you can simply cast:

SELECT md5(random()::text || clock_timestamp()::text)::uuid

How to generate a random string of 20 characters

public String randomString(String chars, int length) {
  Random rand = new Random();
  StringBuilder buf = new StringBuilder();
  for (int i=0; i<length; i++) {
    buf.append(chars.charAt(rand.nextInt(chars.length())));
  }
  return buf.toString();
}

Make Https call using HttpClient

There is a non-global setting at the level of HttpClientHandler:

var handler = new HttpClientHandler()
{
    SslProtocols = SslProtocols.Tls12 | SslProtocols.Tls11 | SslProtocols.Tls
};

var client = new HttpClient(handler);

Thus one enables latest TLS versions.

Note, that the default value SslProtocols.Default is actually SslProtocols.Ssl3 | SslProtocols.Tls (checked for .Net Core 2.1 and .Net Framework 4.7.1).

Unable to Build using MAVEN with ERROR - Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile

For me, I changed C:\apps\Java\jdk1.8_162\bin\javac.exe to C:\apps\Java\jdk1.8_162\bin\javacpl.exe Since there was no executable with that name in the bin folder. That worked.

pip install returning invalid syntax

The problem is the OS can’t find Pip. Pip helps you install packages MODIFIED SOME GREAT ANSWERS TO BE BETTER

Method 1 Go to path of python, then search for pip

  1. open cmd.exe
  2. write the following command:

E.g

cd C:\Users\Username\AppData\Local\Programs\Python\Python37-32

In this directory, search pip with python -m pip then install package

E.g

python -m pip install ipywidgets

-m module-name Searches sys.path for the named module and runs the corresponding .py file as a script.

OR

GO TO scripts from CMD. This is where Pip stays :)

cd C:\Users\User name\AppData\Local\Programs\Python\Python37-32\Scripts>

Then

pip install anypackage

How to query MongoDB with "like"?

As Mongo shell support regex, that's completely possible.

db.users.findOne({"name" : /.*sometext.*/});

If we want the query to be case-insensitive, we can use "i" option, like shown below:

db.users.findOne({"name" : /.*sometext.*/i});

UnsupportedClassVersionError: JVMCFRE003 bad major version in WebSphere AS 7

I was getting this error in websphere 8.5:

java.lang.UnsupportedClassVersionError: JVMCFRE003 bad major version; class=com/xxx/Whatever, offset=6

I had my project JDK level set at 1.7 in eclipse and was8 by default runs on JDK 1.6 so there was a clash. I had to install the optional SDK 1.7 to my websphere server and then the problem went away. I guess I could have also set my project level down to 1.6 in eclipse but I wanted to code to 1.7.

Why is the console window closing immediately once displayed my output?

The code is finished, to continue you need to add this:

Console.ReadLine();

or

Console.Read();

WARNING: UNPROTECTED PRIVATE KEY FILE! when trying to SSH into Amazon EC2 Instance

To fix this,

  1. you’ll need to reset the permissions back to default:

    sudo chmod 600 ~/.ssh/id_rsa
    sudo chmod 600 ~/.ssh/id_rsa.pub
    

    If you are getting another error:

    • Are you sure you want to continue connecting (yes/no)? yes
    • Failed to add the host to the list of known hosts (/home/geek/.ssh/known_hosts).
  2. This means that the permissions on that file are also set incorrectly, and can be adjusted with this:

    sudo chmod 644 ~/.ssh/known_hosts
    
  1. Finally, you may need to adjust the directory permissions as well:

    sudo chmod 755 ~/.ssh
    

This should get you back up and running.

Count number of rows within each group

The simple option to use with aggregate is the length function which will give you the length of the vector in the subset. Sometimes a little more robust is to use function(x) sum( !is.na(x) ).

How to keep a Python script output window open?

Try this,

import sys

stat='idlelib' in sys.modules

if stat==False:
    input()

This will only stop console window, not the IDLE.

Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04

I have faced a similar error. I checked the log in /var/log/apache2/error.log and found an UnexpectedValueException

I changed the owner to my apache user of the storage folder under the project dir.

sudo chown -R www-data:www-data ./storage

In my case apache2 process owner is www-data, so change this to yours, this can be found in apache2 config file. Hope this is useful to you.

how to evenly distribute elements in a div next to each other?

In the 'old days' you'd use a table and your menu items would be evenly spaced without having to explicitly state the width for the number of items.

If it wasn't for IE 6 and 7 (if that is of concern) then you can do the same in CSS.

<div class="demo">
    <span>Span 1</span>
    <span>Span 2</span>
    <span>Span 3</span>
</div>

CSS:

div.demo {
    display: table;
    width: 100%;
    table-layout: fixed;    /* For cells of equal size */
}
div.demo span {
    display: table-cell;
    text-align: center;
}

Without having to adjust for the number of items.

Example without table-layout:fixed - the cells are evenly distributed across the full width, but they are not necessarily of equal size since their width is determined by their contents.

Example with table-layout:fixed - the cells are of equal size, regardless of their contents. (Thanks to @DavidHerse in comments for this addition.)

If you want the first and last menu elements to be left and right justified, then you can add the following CSS:

div.demo span:first-child {
    text-align: left;
}
div.demo span:last-child {
    text-align: right;
}

Spring security CORS Filter

Class WebMvcConfigurerAdapter is deprecated as of 5.0 WebMvcConfigurer has default methods and can be implemented directly without the need for this adapter. For this case:

@Configuration
@EnableWebMvc
public class WebMvcConfig implements WebMvcConfigurer {
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**").allowedOrigins("http://localhost:3000");
    }
}

See also: Same-Site flag for session cookie

Group by with union mysql select query

Try this EDITED:

(SELECT COUNT(motorbike.owner_id),owner.name,transport.type FROM transport,owner,motorbike WHERE transport.type='motobike' AND owner.owner_id=motorbike.owner_id AND transport.type_id=motorbike.motorbike_id GROUP BY motorbike.owner_id)

UNION ALL

(SELECT COUNT(car.owner_id),owner.name,transport.type FROM transport,owner,car WHERE transport.type='car' AND owner.owner_id=car.owner_id AND transport.type_id=car.car_id GROUP BY car.owner_id)

Download all stock symbol list of a market

This may be old, but... if you change the link in google stock list as below:

https://www.google.com/finance?q=%5B(exchange%20%3D%3D%20%22NASDAQ%22)%5D&restype=company&noIL=1&num=30000

  • note for the noIL=1&num=30000

It means, starting for row 1 to 30000. It shows all results in one page.

You may automate it using any language or just export the table to excel.

Hope it helps.

How to merge a list of lists with same type of items to a single list of items?

Do you mean this?

var listOfList = new List<List<int>>() {
    new List<int>() { 1, 2 },
    new List<int>() { 3, 4 },
    new List<int>() { 5, 6 }
};
var list = new List<int> { 9, 9, 9 };
var result = list.Concat(listOfList.SelectMany(x => x));

foreach (var x in result) Console.WriteLine(x);

Results in: 9 9 9 1 2 3 4 5 6

Which HTML elements can receive focus?

Maybe this one can help:

_x000D_
_x000D_
function focus(el){_x000D_
 el.focus();_x000D_
 return el==document.activeElement;_x000D_
}
_x000D_
_x000D_
_x000D_

return value: true = success, false = failed

Reff: https://developer.mozilla.org/en-US/docs/Web/API/DocumentOrShadowRoot/activeElement https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/focus

Attempt by security transparent method 'WebMatrix.WebData.PreApplicationStartCode.Start()'

I installed webapi with it via the helppages nuget package. That package replaced most of the asp.net mvc 4 binaries with beta versions which didn't work well together with the rest of the project. Fix was to restore the original mvc 4 dll's and all was good.

grep from tar.gz without extracting [faster one]

Am trying to grep pattern from dozen files .tar.gz but its very slow

tar -ztf file.tar.gz | while read FILENAME
do
        if tar -zxf file.tar.gz "$FILENAME" -O | grep "string" > /dev/null
        then
                echo "$FILENAME contains string"
        fi
done

That's actually very easy with ugrep option -z:

-z, --decompress
        Decompress files to search, when compressed.  Archives (.cpio,
        .pax, .tar, and .zip) and compressed archives (e.g. .taz, .tgz,
        .tpz, .tbz, .tbz2, .tb2, .tz2, .tlz, and .txz) are searched and
        matching pathnames of files in archives are output in braces.  If
        -g, -O, -M, or -t is specified, searches files within archives
        whose name matches globs, matches file name extensions, matches
        file signature magic bytes, or matches file types, respectively.
        Supported compression formats: gzip (.gz), compress (.Z), zip,
        bzip2 (requires suffix .bz, .bz2, .bzip2, .tbz, .tbz2, .tb2, .tz2),
        lzma and xz (requires suffix .lzma, .tlz, .xz, .txz).

Which requires just one command to search file.tar.gz as follows:

ugrep -z "string" file.tar.gz

This greps each of the archived files to display matches. Archived filenames are shown in braces to distinguish them from ordinary filenames. For example:

$ ugrep -z "Hello" archive.tgz
{Hello.bat}:echo "Hello World!"
Binary file archive.tgz{Hello.class} matches
{Hello.java}:public class Hello // prints a Hello World! greeting
{Hello.java}:  { System.out.println("Hello World!");
{Hello.pdf}:(Hello)
{Hello.sh}:echo "Hello World!"
{Hello.txt}:Hello

If you just want the file names, use option -l (--files-with-matches) and customize the filename output with option --format="%z%~" to get rid of the braces:

$ ugrep -z Hello -l --format="%z%~" archive.tgz
Hello.bat
Hello.class
Hello.java
Hello.pdf
Hello.sh
Hello.txt