Programs & Examples On #Relationship

Questions in this tag typically involve the association that a set of data has with other set(s) of data.

Delete all nodes and relationships in neo4j 1.8

you are probably doing it correct, only the dashboard shows just the higher ID taken, and thus the number of "active" nodes, relationships, although there are none. it is just informative.

to be sure you have an empty graph, run this command:

START n=node(*) return count(n);
START r=rel(*) return count(r);

if both give you 0, your deletion was succesfull.

Laravel where on relationship object

    return Deal::with(["redeem" => function($q){
        $q->where('user_id', '=', 1);
    }])->get();

this worked for me

Meaning of "n:m" and "1:n" in database design

Many to Many (n:m) One to Many (1:n)

Laravel - Eloquent "Has", "With", "WhereHas" - What do they mean?

With

with() is for eager loading. That basically means, along the main model, Laravel will preload the relationship(s) you specify. This is especially helpful if you have a collection of models and you want to load a relation for all of them. Because with eager loading you run only one additional DB query instead of one for every model in the collection.

Example:

User > hasMany > Post

$users = User::with('posts')->get();
foreach($users as $user){
    $users->posts; // posts is already loaded and no additional DB query is run
}

Has

has() is to filter the selecting model based on a relationship. So it acts very similarly to a normal WHERE condition. If you just use has('relation') that means you only want to get the models that have at least one related model in this relation.

Example:

User > hasMany > Post

$users = User::has('posts')->get();
// only users that have at least one post are contained in the collection

WhereHas

whereHas() works basically the same as has() but allows you to specify additional filters for the related model to check.

Example:

User > hasMany > Post

$users = User::whereHas('posts', function($q){
    $q->where('created_at', '>=', '2015-01-01 00:00:00');
})->get();
// only users that have posts from 2015 on forward are returned

Implementation difference between Aggregation and Composition in Java

Composition

final class Car {

  private final Engine engine;

  Car(EngineSpecs specs) {
    engine = new Engine(specs);
  }

  void move() {
    engine.work();
  }
}

Aggregation

final class Car {

  private Engine engine;

  void setEngine(Engine engine) {
    this.engine = engine;
  }

  void move() {
    if (engine != null)
      engine.work();
  }
}

In the case of composition, the Engine is completely encapsulated by the Car. There is no way for the outside world to get a reference to the Engine. The Engine lives and dies with the car. With aggregation, the Car also performs its functions through an Engine, but the Engine is not always an internal part of the Car. Engines may be swapped, or even completely removed. Not only that, but the outside world can still have a reference to the Engine, and tinker with it regardless of whether it's in the Car.

How to show a confirm message before delete?

Try this. It works for me

 <a href="delete_methode_link" onclick="return confirm('Are you sure you want to Remove?');">Remove</a>

How to make a JSON call to a url?

A standard http GET request should do it. Then you can use JSON.parse() to make it into a json object.

function Get(yourUrl){
    var Httpreq = new XMLHttpRequest(); // a new request
    Httpreq.open("GET",yourUrl,false);
    Httpreq.send(null);
    return Httpreq.responseText;          
}

then

var json_obj = JSON.parse(Get(yourUrl));
console.log("this is the author name: "+json_obj.author_name);

that's basically it

How do I import modules or install extensions in PostgreSQL 9.1+?

For the postgrersql10

I have solved it with

yum install postgresql10-contrib

Don't forget to activate extensions in postgresql.conf

shared_preload_libraries = 'pg_stat_statements'
pg_stat_statements.track = all

then of course restart

systemctl restart postgresql-10.service 

all of the needed extensions you can find here

/usr/pgsql-10/share/extension/

saving a file (from stream) to disk using c#

For file Type you can rely on FileExtentions and for writing it to disk you can use BinaryWriter. or a FileStream.

Example (Assuming you already have a stream):

FileStream fileStream = File.Create(fileFullPath, (int)stream.Length);
// Initialize the bytes array with the stream length and then fill it with data
byte[] bytesInStream = new byte[stream.Length];
stream.Read(bytesInStream, 0, bytesInStream.Length);    
// Use write method to write to the file specified above
fileStream.Write(bytesInStream, 0, bytesInStream.Length);
//Close the filestream
fileStream.Close();

How do I install cURL on Windows?

You can also use CygWin and install the cURL package. It works very well and flawlessly!!

Using multiple case statements in select query

There are two ways to write case statements, you seem to be using a combination of the two

case a.updatedDate
    when 1760 then 'Entered on' + a.updatedDate
    when 1710 then 'Viewed on' + a.updatedDate
    else 'Last Updated on' + a.updateDate
end

or

case 
    when a.updatedDate = 1760 then 'Entered on' + a.updatedDate
    when a.updatedDate = 1710 then 'Viewed on' + a.updatedDate
    else 'Last Updated on' + a.updateDate
end

are equivalent. They may not work because you may need to convert date types to varchars to append them to other varchars.

Swift: Determine iOS Screen size

In Swift 3.0

let screenSize = UIScreen.main.bounds
let screenWidth = screenSize.width
let screenHeight = screenSize.height

In older swift: Do something like this:

let screenSize: CGRect = UIScreen.mainScreen().bounds

then you can access the width and height like this:

let screenWidth = screenSize.width
let screenHeight = screenSize.height

if you want 75% of your screen's width you can go:

let screenWidth = screenSize.width * 0.75

Swift 4.0

// Screen width.
public var screenWidth: CGFloat {
    return UIScreen.main.bounds.width
}

// Screen height.
public var screenHeight: CGFloat {
    return UIScreen.main.bounds.height
}

In Swift 5.0

let screenSize: CGRect = UIScreen.main.bounds

How to implement 2D vector array?

vector<vector> matrix(row, vector(col, 0));

This will initialize a 2D vector of rows=row and columns = col with all initial values as 0. No need to initialize and use resize.

Since the vector is initialized with size, you can use "[]" operator as in array to modify the vector.

matrix[x][y] = 2;

SCCM 2012 application install "Failed" in client Software Center

The execmgr.log will show the commandline and ccmcache folder used for installation. Typically, required apps don't show on appenforce.log and some clients will have outdated appenforce or no ppenforce.log files. execmgr.log also shows required hidden uninstall actions as well.

You may want to save the blog link. I still reference it from time to time.

How to make a vertical SeekBar in Android?

When moving the thumb with an EditText, the Vertical Seekbar setProgress may not work. The following code can help:

    @Override
public synchronized void setProgress(int progress) {
    super.setProgress(progress);
    updateThumb();
}

private void updateThumb() {
    onSizeChanged(getWidth(), getHeight(), 0, 0);
}

This snippet code found here: https://stackoverflow.com/a/33064140/2447726

JPA: difference between @JoinColumn and @PrimaryKeyJoinColumn?

I know this is an old post, but a good time to use PrimaryKeyColumn would be if you wanted a unidirectional relationship or had multiple tables all sharing the same id.

In general this is a bad idea and it would be better to use foreign key relationships with JoinColumn.

Having said that, if you are working on an older database that used a system like this then that would be a good time to use it.

Android - java.lang.SecurityException: Permission Denial: starting Intent

You need to set android:exported="true" in your AndroidManifest.xml file where you declare this Activity:

<activity
    android:name="com.example.lib.MainActivity"
    android:label="LibMain" 
    android:exported="true">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" >
        </action>
    </intent-filter>
</activity>

How to add font-awesome to Angular 2 + CLI project

Using LESS (not SCSS) and Angular 2.4.0 and standard Webpack (not Angular CLI, the following worked for me:

npm install --save font-awesome

and (in my app.component.less):

@import "~font-awesome/less/font-awesome.less";

and of course you may need this obvious and highly intuitive snippet (in module.loaders in webpack.conf)

        {
            test: /\.(png|jpe?g|gif|svg|woff|woff2|ttf|eot|ico)(\?(v=)?(\d+)(\.\d+)*)?$/,
            loader: 'file?name=graphics/[name].[ext]'
        },

The loader is there to fix webpack errors of the kind

"Module parse failed: \node_modules\font-awesome\fonts\fontawesome-webfont.svg?v=4.7.0 Unexpected token (1:0)" 

and the regexp matches those svg-references (with or without version specification). Depending on your webpack setup you might not need it or you may need something else.

Hide particular div onload and then show div after click

You are missing # hash character before id selectors, this should work:

$(document).ready(function() {
    $("#div2").hide();

    $("#preview").click(function() {
      $("#div1").hide();
      $("#div2").show();
    });

});

Learn More about jQuery ID Selectors

Checking if output of a command contains a certain string in a shell script

A clean if/else conditional shell script:

if ./somecommand | grep -q 'some_string'; then
  echo "exists"
else
  echo "doesn't exist"
fi

Get domain name

I'm going to add an answer to try to clear up a few things here as there seems to be some confusion. The main issue is that people are asking the wrong question, or at least not being specific enough.

What does a computer's "domain" actually mean?

When we talk about a computer's "domain", there are several things that we might be referring to. What follows is not an exhaustive list, but it covers the most common cases:

  • A user or computer security principal may belong to an Active Directory domain.
  • The network stack's primary DNS search suffix may be referred to as the computer's "domain".
  • A DNS name that resolves to the computer's IP address may be referred to as the computer's "domain".

Which one do I want?

This is highly dependent on what you are trying to do. The original poster of this question was looking for the computer's "Active Directory domain", which probably means they are looking for the domain to which either the computer's security principal or a user's security principal belongs. Generally you want these when you are trying to talk to Active Directory in some way. Note that the current user principal and the current computer principal are not necessarily in the same domain.

Pieter van Ginkel's answer is actually giving you the local network stack's primary DNS suffix (the same thing that's shown in the top section of the output of ipconfig /all). In the 99% case, this is probably the same as the domain to which both the computer's security principal and the currently authenticated user's principal belong - but not necessarily. Generally this is what you want when you are trying to talk to devices on the LAN, regardless of whether or not the devices are anything to do with Active Directory. For many applications, this will still be a "good enough" answer for talking to Active Directory.

The last option, a DNS name, is a lot fuzzier and more ambiguous than the other two. Anywhere between zero and infinity DNS records may resolve to a given IP address - and it's not necessarily even clear which IP address you are interested in. user2031519's answer refers to the value of HTTP_HOST, which is specifically useful when determining how the user resolved your HTTP server in order to send the request you are currently processing. This is almost certainly not what you want if you are trying to do anything with Active Directory.

How do I get them?

Domain of the current user security principal

This one's nice and simple, it's what Tim's answer is giving you.

System.Environment.UserDomainName

Domain of the current computer security principal

This is probably what the OP wanted, for this one we're going to have to ask Active Directory about it.

System.DirectoryServices.ActiveDirectory.Domain.GetComputerDomain()

This one will throw a ActiveDirectoryObjectNotFoundException if the local machine is not part of domain, or the domain controller cannot be contacted.

Network stack's primary DNS suffix

This is what Pieter van Ginkel's answer is giving you. It's probably not exactly what you want, but there's a good chance it's good enough for you - if it isn't, you probably already know why.

System.Net.NetworkInformation.IPGlobalProperties.GetIPGlobalProperties().DomainName

DNS name that resolves to the computer's IP address

This one's tricky and there's no single answer to it. If this is what you are after, comment below and I will happily discuss your use-case and help you to work out the best solution (and expand on this answer in the process).

How to style the parent element when hovering a child element?

As mentioned previously "there is no CSS selector for selecting a parent of a selected child".

So you either:


Here is the example for the javascript/jQuery solution

On the javascript side:

$('#my-id-selector-00').on('mouseover', function(){
  $(this).parent().addClass('is-hover');
}).on('mouseout', function(){
  $(this).parent().removeClass('is-hover');
})

And on the CSS side, you'd have something like this:

.is-hover {
  background-color: red;
}

Change EditText hint color when using TextInputLayout

Refer the below code it worked for me.But it will affect all your controls color.

 <!-- In your style.xml file -->
    <style name="AppTheme" parent="Theme.AppCompat.NoActionBar">
            <!--EditText hint color-->
            <item name="android:textColorHint">@color/default_app_white</item>
           <!-- TextInputLayout text color-->
            <item name="colorControlActivated">@color/default_app_green</item>
            <!-- EditText line color when EditText on-focus-->
            <item name="colorControlHighlight">@color/default_app_green</item>
            <!-- EditText line color when EditText  in un-focus-->
            <item name="colorControlNormal">@color/default_app_white</item>
        </style>

Common HTTPclient and proxy

Here is how I solved this problem for the old (< 4.3) HttpClient (which I cannot upgrade), using the answer of Santosh Singh (who I gave a +1):

HttpClient httpclient = new HttpClient();
if (System.getProperty("http.proxyHost") != null) {
  try {
    HostConfiguration hostConfiguration = httpclient.getHostConfiguration();
    hostConfiguration.setProxy(System.getProperty("http.proxyHost"), Integer.parseInt(System.getProperty("http.proxyPort")));
    httpclient.setHostConfiguration(hostConfiguration);
    this.getLogger().warn("USING PROXY: "+httpclient.getHostConfiguration().getProxyHost());
  } catch (Exception e) {
    throw new ProcessingException("Cannot set proxy!", e);
  }
}

How to save Excel Workbook to Desktop regardless of user?

You've mentioned that they each have their own machines, but if they need to log onto a co-workers machine, and then use the file, saving it through "C:\Users\Public\Desktop\" will make it available to different usernames.

Public Sub SaveToDesktop()
    ThisWorkbook.SaveAs Filename:="C:\Users\Public\Desktop\" & ThisWorkbook.Name & "_copy", _ 
    FileFormat:=xlOpenXMLWorkbookMacroEnabled
End Sub

I'm not sure whether this would be a requirement, but may help!

Eclipse reports rendering library more recent than ADT plug-in

Change android version while rendering layout.

enter image description here

Change in API version 18 to 17 work for me.

Edit: Solution worked for Android Studio too.

Formatting a Date String in React Native

The Date constructor is very picky about what it allows. The string you pass in must be supported by Date.parse(), and if it is unsupported, it will return NaN. Different versions of JavaScript do support different formats, if those formats deviate from the official ISO documentation.

See the examples here for what is supported: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/parse

How do I lock the orientation to portrait mode in a iPhone Web Application?

// CSS hack to prevent layout breaking in landscape
// e.g. screens larger than 320px  
html {
  width: 320px;
  overflow-x: hidden;
}

This, or a similar CSS solution, will at least preserve your layout if that is what you are after.

The root solution is accounting for device's capabilities rather than attempting to limit them. If the device doesn't allow you the appropriate limitation than a simple hack is your best bet since the design is essentially incomplete. The simpler the better.

How do I center floated elements?

<!DOCTYPE html>
<html>
<head>
    <title>float object center</title>
    <style type="text/css">
#warp{
    width:500px;
    margin:auto;
}
.ser{
width: 200px;
background-color: #ffffff;
display: block;
float: left;
margin-right: 50px;
}
.inim{
    width: 120px;
    margin-left: 40px;
}

    </style>
</head>
<body>



<div id="warp">
            <div class="ser">
              <img class="inim" src="http://123greetingsquotes.com/wp-content/uploads/2015/01/republic-day-parade-india-images-120x120.jpg">

              </div>
           <div class="ser">
             <img class="inim" sr`enter code here`c="http://123greetingsquotes.com/wp-content/uploads/2015/01/republic-day-parade-india-images-120x120.jpg">

             </div>
        </div>

</body>
</html>

step 1

create two or more div's you want and give them a definite width like 100px for each then float it left or right

step 2

then warp these two div's in another div and give it the width of 200px. to this div apply margin auto. boom it works pretty well. check the above example.

Insert into a MySQL table or update if exists

Any of these solution will work regarding your question:

INSERT IGNORE INTO table (id, name, age) VALUES (1, "A", 19);

or

INSERT INTO TABLE (id, name, age) VALUES(1, "A", 19) 
    ON DUPLICATE KEY UPDATE NAME = "A", AGE = 19;  

or

REPLACE INTO table (id, name, age) VALUES(1, "A", 19);

If you want to know in details regarding these statement visit this link

Change div height on button click

Do this:

function changeHeight() {
document.getElementById('chartdiv').style.height = "200px"
}
<button type="button" onClick="changeHeight();"> Click Me!</button>

Storyboard - refer to ViewController in AppDelegate

If you use XCode 5 you should do it in a different way.

  • Select your UIViewController in UIStoryboard
  • Go to the Identity Inspector on the right top pane
  • Check the Use Storyboard ID checkbox
  • Write a unique id to the Storyboard ID field

Then write your code.

// Override point for customization after application launch.

if (<your implementation>) {
    UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"Main" 
                                                             bundle: nil];
    YourViewController *yourController = (YourViewController *)[mainStoryboard 
      instantiateViewControllerWithIdentifier:@"YourViewControllerID"];
    self.window.rootViewController = yourController;
}

return YES;

C: socket connection timeout

Here is a modern connect_with_timeout implementation, using poll, with proper error and signal handling:

#include <sys/socket.h>
#include <fcntl.h>
#include <poll.h>
#include <time.h>

int connect_with_timeout(int sockfd, const struct sockaddr *addr, socklen_t addrlen, unsigned int timeout_ms) {
    int rc = 0;
    // Set O_NONBLOCK
    int sockfd_flags_before;
    if((sockfd_flags_before=fcntl(sockfd,F_GETFL,0)<0)) return -1;
    if(fcntl(sockfd,F_SETFL,sockfd_flags_before | O_NONBLOCK)<0) return -1;
    // Start connecting (asynchronously)
    do {
        if (connect(sockfd, addr, addrlen)<0) {
            // Did connect return an error? If so, we'll fail.
            if ((errno != EWOULDBLOCK) && (errno != EINPROGRESS)) {
                rc = -1;
            }
            // Otherwise, we'll wait for it to complete.
            else {
                // Set a deadline timestamp 'timeout' ms from now (needed b/c poll can be interrupted)
                struct timespec now;
                if(clock_gettime(CLOCK_MONOTONIC, &now)<0) { rc=-1; break; }
                struct timespec deadline = { .tv_sec = now.tv_sec,
                                             .tv_nsec = now.tv_nsec + timeout_ms*1000000l};
                // Wait for the connection to complete.
                do {
                    // Calculate how long until the deadline
                    if(clock_gettime(CLOCK_MONOTONIC, &now)<0) { rc=-1; break; }
                    int ms_until_deadline = (int)(  (deadline.tv_sec  - now.tv_sec)*1000l
                                                  + (deadline.tv_nsec - now.tv_nsec)/1000000l);
                    if(ms_until_deadline<0) { rc=0; break; }
                    // Wait for connect to complete (or for the timeout deadline)
                    struct pollfd pfds[] = { { .fd = sockfd, .events = POLLOUT } };
                    rc = poll(pfds, 1, ms_until_deadline);
                    // If poll 'succeeded', make sure it *really* succeeded
                    if(rc>0) {
                        int error = 0; socklen_t len = sizeof(error);
                        int retval = getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &error, &len);
                        if(retval==0) errno = error;
                        if(error!=0) rc=-1;
                    }
                }
                // If poll was interrupted, try again.
                while(rc==-1 && errno==EINTR);
                // Did poll timeout? If so, fail.
                if(rc==0) {
                    errno = ETIMEDOUT;
                    rc=-1;
                }
            }
        }
    } while(0);
    // Restore original O_NONBLOCK state
    if(fcntl(sockfd,F_SETFL,sockfd_flags_before)<0) return -1;
    // Success
    return rc;
}

When do I need to do "git pull", before or after "git add, git commit"?

I think that the best way to do this is:

Stash your local changes:

git stash

Update the branch to the latest code

git pull

Merge your local changes into the latest code:

git stash apply

Add, commit and push your changes

git add
git commit
git push

In my experience this is the path to least resistance with Git (on the command line anyway).

How do you make Vim unhighlight what you searched for?

Also, if you want to have a toogle and be sure that the highlight will be reactivate for the next time you search something, you can use this

nmap <F12> :set hls!<CR>
nnoremap / :set hls<CR>/

How to restore PostgreSQL dump file into Postgres databases?

The problem with your attempt at the psql command line is the direction of the slashes:

newTestDB-# /i E:\db-rbl-restore-20120511_Dump-20120514.sql   # incorrect
newTestDB-# \i E:/db-rbl-restore-20120511_Dump-20120514.sql   # correct

To be clear, psql commands start with a backslash, so you should have put \i instead. What happened as a result of your typo is that psql ignored everything until finding the first \, which happened to be followed by db, and \db happens to be the psql command for listing table spaces, hence why the output was a List of tablespaces. It was not a listing of "default tables of PostgreSQL" as you said.

Further, it seems that psql expects the filepath argument to delimit directories using the forward slash regardless of OS (thus on Windows this would be counter-intuitive).

It is worth noting that your attempt at "elevating permissions" had no relation to the outcome of the command you attempted to execute. Also, you did not say what caused the supposed "Permission Denied" error.

Finally, the extension on the dump file does not matter, in fact you don't even need an extension. Indeed, pgAdmin suggests a .backup extension when selecting a backup filename, but you can actually make it whatever you want, again, including having no extension at all. The problem is that pgAdmin seems to only allow a "Restore" of "Custom or tar" or "Directory" dumps (at least this is the case in the MAC OS X version of the app), so just use the psql \i command as shown above.

SCRIPT438: Object doesn't support property or method IE

My problem was having type="application/javascript" on the <script> tag for jQuery. IE8 does not like this! If your webpage is HTML5 you don't even need to declare the type, otherwise go with type="text/javascript" instead.

Permission to write to the SD card

You're right that the SD Card directory is /sdcard but you shouldn't be hard coding it. Instead, make a call to Environment.getExternalStorageDirectory() to get the directory:

File sdDir = Environment.getExternalStorageDirectory();

If you haven't done so already, you will need to give your app the correct permission to write to the SD Card by adding the line below to your Manifest:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

How to get correct timestamp in C#

For UTC:

string unixTimestamp = Convert.ToString((int)DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1)).TotalSeconds);

For local system:

string unixTimestamp = Convert.ToString((int)DateTime.Now.Subtract(new DateTime(1970, 1, 1)).TotalSeconds);

How to do a GitHub pull request

I wrote a bash program that does all the work of setting up a PR branch for you. It performs forking if needed, syncing with the upstream, setting up upstream remote, etc. and you just need to commit your modifications, push and submit a PR.

Here is how you run it:

github-make-pr-branch ssh your-github-username orig_repo_user orig_repo_name new-feature

You will find the program here and its repository also includes a step-by-step guide to performing the same process manually if you'd like to understand how it works, and also extra information on how to keep your feature branch up-to-date with the upstream master and other useful tidbits.

How to set the custom border color of UIView programmatically?

swift 3

func borderColor(){

    self.viewMenuItems.layer.cornerRadius = 13
    self.viewMenuItems.layer.borderWidth = 1
    self.viewMenuItems.layer.borderColor = UIColor.white.cgColor
}

Windows XP or later Windows: How can I run a batch file in the background with no window displayed?

Do you need the second batch file to run asynchronously? Typically one batch file runs another synchronously with the call command, and the second one would share the first one's window.

You can use start /b second.bat to launch a second batch file asynchronously from your first that shares your first one's window. If both batch files write to the console simultaneously, the output will be overlapped and probably indecipherable. Also, you'll want to put an exit command at the end of your second batch file, or you'll be within a second cmd shell once everything is done.

Find duplicate values in R

You could use table, i.e.

n_occur <- data.frame(table(vocabulary$id))

gives you a data frame with a list of ids and the number of times they occurred.

n_occur[n_occur$Freq > 1,]

tells you which ids occurred more than once.

vocabulary[vocabulary$id %in% n_occur$Var1[n_occur$Freq > 1],]

returns the records with more than one occurrence.

Unable to open debugger port in IntelliJ

Your Service/ Application might already be running. In Search enter Services and you will get list of services. Stop yours and then try again.

Cast object to T

try

if (readData is T)
    return (T)(object)readData;

jQuery: keyPress Backspace won't fire?

Use keyup instead of keypress. This gets all the key codes when the user presses something

How is __eq__ handled in Python and in what order?

The a == b expression invokes A.__eq__, since it exists. Its code includes self.value == other. Since int's don't know how to compare themselves to B's, Python tries invoking B.__eq__ to see if it knows how to compare itself to an int.

If you amend your code to show what values are being compared:

class A(object):
    def __eq__(self, other):
        print("A __eq__ called: %r == %r ?" % (self, other))
        return self.value == other
class B(object):
    def __eq__(self, other):
        print("B __eq__ called: %r == %r ?" % (self, other))
        return self.value == other

a = A()
a.value = 3
b = B()
b.value = 4
a == b

it will print:

A __eq__ called: <__main__.A object at 0x013BA070> == <__main__.B object at 0x013BA090> ?
B __eq__ called: <__main__.B object at 0x013BA090> == 3 ?

Convert datetime value into string

This is super old, but I figured I'd add my 2c. DATE_FORMAT does indeed return a string, but I was looking for the CAST function, in the situation that I already had a datetime string in the database and needed to pattern match against it:

http://dev.mysql.com/doc/refman/5.0/en/cast-functions.html

In this case, you'd use:

CAST(date_value AS char)

This answers a slightly different question, but the question title seems ambiguous enough that this might help someone searching.

try/catch with InputMismatchException creates infinite loop

another option is to define Scanner input = new Scanner(System.in); inside the try block, this will create a new object each time you need to re-enter the values.

Most useful NLog configurations

Reporting to an external website/database

I wanted a way to simply and automatically report errors (since users often don't) from our applications. The easiest solution I could come up with was a public URL - a web page which could take input and store it to a database - that is sent data upon an application error. (The database could then be checked by a dev or a script to know if there are new errors.)

I wrote the web page in PHP and created a mysql database, user, and table to store the data. I decided on four user variables, an id, and a timestamp. The possible variables (either included in the URL or as POST data) are:

  • app (application name)
  • msg (message - e.g. Exception occurred ...)
  • dev (developer - e.g. Pat)
  • src (source - this would come from a variable pertaining to the machine on which the app was running, e.g. Environment.MachineName or some such)
  • log (a log file or verbose message)

(All of the variables are optional, but nothing is reported if none of them are set - so if you just visit the website URL nothing is sent to the db.)

To send the data to the URL, I used NLog's WebService target. (Note, I had a few problems with this target at first. It wasn't until I looked at the source that I figured out that my url could not end with a /.)

All in all, it's not a bad system for keeping tabs on external apps. (Of course, the polite thing to do is to inform your users that you will be reporting possibly sensitive data and to give them a way to opt in/out.)

MySQL stuff

(The db user has only INSERT privileges on this one table in its own database.)

CREATE TABLE `reports` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `ts` timestamp NULL DEFAULT CURRENT_TIMESTAMP,
  `applicationName` text,
  `message` text,
  `developer` text,
  `source` text,
  `logData` longtext,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8 COMMENT='storage place for reports from external applications'

Website code

(PHP 5.3 or 5.2 with PDO enabled, file is index.php in /report folder)

<?php
$app = $_REQUEST['app'];
$msg = $_REQUEST['msg'];
$dev = $_REQUEST['dev'];
$src = $_REQUEST['src'];
$log = $_REQUEST['log'];

$dbData =
    array(  ':app' => $app,
            ':msg' => $msg,
            ':dev' => $dev,
            ':src' => $src,
            ':log' => $log
    );
//print_r($dbData); // For debugging only! This could allow XSS attacks.
if(isEmpty($dbData)) die("No data provided");

try {
$db = new PDO("mysql:host=$host;dbname=reporting", "reporter", $pass, array(
    PDO::ATTR_PERSISTENT => true
));
$s = $db->prepare("INSERT INTO reporting.reports 
    (
    applicationName, 
    message, 
    developer, 
    source, 
    logData
    )
    VALUES
    (
    :app, 
    :msg, 
    :dev, 
    :src, 
    :log
    );"
    );
$s->execute($dbData);
print "Added report to database";
} catch (PDOException $e) {
// Sensitive information can be displayed if this exception isn't handled
//print "Error!: " . $e->getMessage() . "<br/>";
die("PDO error");
}

function isEmpty($array = array()) {
    foreach ($array as $element) {
        if (!empty($element)) {
            return false;
        }
    }
    return true;
}
?>

App code (NLog config file)

<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      throwExceptions="true" internalLogToConsole="true" internalLogLevel="Warn" internalLogFile="nlog.log">
    <variable name="appTitle" value="My External App"/>
    <variable name="csvPath" value="${specialfolder:folder=Desktop:file=${appTitle} log.csv}"/>
    <variable name="developer" value="Pat"/>

    <targets async="true">
        <!--The following will keep the default number of log messages in a buffer and write out certain levels if there is an error and other levels if there is not. Messages that appeared before the error (in code) will be included, since they are buffered.-->
        <wrapper-target xsi:type="BufferingWrapper" name="smartLog">
            <wrapper-target xsi:type="PostFilteringWrapper">
                <target xsi:type="File" fileName="${csvPath}"
                archiveAboveSize="4194304" concurrentWrites="false" maxArchiveFiles="1" archiveNumbering="Sequence"
                >
                    <layout xsi:type="CsvLayout" delimiter="Comma" withHeader="false">
                        <column name="time" layout="${longdate}" />
                        <column name="level" layout="${level:upperCase=true}"/>
                        <column name="message" layout="${message}" />
                        <column name="callsite" layout="${callsite:includeSourcePath=true}" />
                        <column name="stacktrace" layout="${stacktrace:topFrames=10}" />
                        <column name="exception" layout="${exception:format=ToString}"/>
                        <!--<column name="logger" layout="${logger}"/>-->
                    </layout>
                </target>

                 <!--during normal execution only log certain messages--> 
                <defaultFilter>level >= LogLevel.Warn</defaultFilter>

                 <!--if there is at least one error, log everything from trace level--> 
                <when exists="level >= LogLevel.Error" filter="level >= LogLevel.Trace" />
            </wrapper-target>
        </wrapper-target>

        <target xsi:type="WebService" name="web"
                url="http://example.com/report" 
                methodName=""
                namespace=""
                protocol="HttpPost"
                >
            <parameter name="app" layout="${appTitle}"/>
            <parameter name="msg" layout="${message}"/>
            <parameter name="dev" layout="${developer}"/>
            <parameter name="src" layout="${environment:variable=UserName} (${windows-identity}) on ${machinename} running os ${environment:variable=OSVersion} with CLR v${environment:variable=Version}"/>
            <parameter name="log" layout="${file-contents:fileName=${csvPath}}"/>
        </target>

    </targets>

    <rules>
        <logger name="*" minlevel="Trace" writeTo="smartLog"/>
        <logger name="*" minlevel="Error" writeTo="web"/>
    </rules>
</nlog>

Note: there may be some issues with the size of the log file, but I haven't figured out a simple way to truncate it (e.g. a la *nix's tail command).

How to do a simple file search in cmd

Problem with DIR is that it will return wrong answers. If you are looking for DOC in a folder by using DIR *.DOC it will also give you the DOCX. Searching for *.HTM will also give the HTML and so on...

convert from Color to brush

Brush brush = new SolidColorBrush(color);

The other way around:

if (brush is SolidColorBrush colorBrush)
    Color color = colorBrush.Color;

Or something like that.

Point being not all brushes are colors but you could turn all colors into a (SolidColor)Brush.

how to redirect to external url from c# controller

Use the Controller's Redirect() method.

public ActionResult YourAction()
{
    // ...
    return Redirect("http://www.example.com");
}

Update

You can't directly perform a server side redirect from an ajax response. You could, however, return a JsonResult with the new url and perform the redirect with javascript.

public ActionResult YourAction()
{
    // ...
    return Json(new {url = "http://www.example.com"});
}

$.post("@Url.Action("YourAction")", function(data) {
    window.location = data.url;
});

How to disable gradle 'offline mode' in android studio?

Gradle is in offline mode, which means that it won't go to the network to resolve dependencies.

Go to Preferences > Gradle and uncheck "Offline work".

Android turn On/Off WiFi HotSpot programmatically

I have publish unofficial api's for same, it's contains more than just hotspot turn on/off. link

For API's DOC - link.

Best way to convert an ArrayList to a string

Loop through it and call toString. There isn't a magic way, and if there were, what do you think it would be doing under the covers other than looping through it? About the only micro-optimization would be to use StringBuilder instead of String, and even that isn't a huge win - concatenating strings turns into StringBuilder under the covers, but at least if you write it that way you can see what's going on.

StringBuilder out = new StringBuilder();
for (Object o : list)
{
  out.append(o.toString());
  out.append("\t");
}
return out.toString();

Update div with jQuery ajax response html

Almost 5 years later, I think my answer can reduce a little bit the hard work of many people.

Update an element in the DOM with the HTML from the one from the ajax call can be achieved that way

$('#submitform').click(function() {
     $.ajax({
     url: "getinfo.asp",
     data: {
         txtsearch: $('#appendedInputButton').val()
     },
     type: "GET",
     dataType : "html",
     success: function (data){
         $('#showresults').html($('#showresults',data).html());
         // similar to $(data).find('#showresults')
     },
});

or with replaceWith()

// codes

success: function (data){
   $('#showresults').replaceWith($('#showresults',data));
},

The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead

  1. Why is this happening?

    The entire ext/mysql PHP extension, which provides all functions named with the prefix mysql_, was officially deprecated in PHP v5.5.0 and removed in PHP v7.

    It was originally introduced in PHP v2.0 (November 1997) for MySQL v3.20, and no new features have been added since 2006. Coupled with the lack of new features are difficulties in maintaining such old code amidst complex security vulnerabilities.

    The manual has contained warnings against its use in new code since June 2011.

  2. How can I fix it?

    As the error message suggests, there are two other MySQL extensions that you can consider: MySQLi and PDO_MySQL, either of which can be used instead of ext/mysql. Both have been in PHP core since v5.0, so if you're using a version that is throwing these deprecation errors then you can almost certainly just start using them right away—i.e. without any installation effort.

    They differ slightly, but offer a number of advantages over the old extension including API support for transactions, stored procedures and prepared statements (thereby providing the best way to defeat SQL injection attacks). PHP developer Ulf Wendel has written a thorough comparison of the features.

    Hashphp.org has an excellent tutorial on migrating from ext/mysql to PDO.

  3. I understand that it's possible to suppress deprecation errors by setting error_reporting in php.ini to exclude E_DEPRECATED:

    error_reporting = E_ALL ^ E_DEPRECATED
    

    What will happen if I do that?

    Yes, it is possible to suppress such error messages and continue using the old ext/mysql extension for the time being. But you really shouldn't do this—this is a final warning from the developers that the extension may not be bundled with future versions of PHP (indeed, as already mentioned, it has been removed from PHP v7). Instead, you should take this opportunity to migrate your application now, before it's too late.

    Note also that this technique will suppress all E_DEPRECATED messages, not just those to do with the ext/mysql extension: therefore you may be unaware of other upcoming changes to PHP that would affect your application code. It is, of course, possible to only suppress errors that arise on the expression at issue by using PHP's error control operator—i.e. prepending the relevant line with @—however this will suppress all errors raised by that expression, not just E_DEPRECATED ones.


What should you do?

  • You are starting a new project.

    There is absolutely no reason to use ext/mysql—choose one of the other, more modern, extensions instead and reap the rewards of the benefits they offer.

  • You have (your own) legacy codebase that currently depends upon ext/mysql.

    It would be wise to perform regression testing: you really shouldn't be changing anything (especially upgrading PHP) until you have identified all of the potential areas of impact, planned around each of them and then thoroughly tested your solution in a staging environment.

    • Following good coding practice, your application was developed in a loosely integrated/modular fashion and the database access methods are all self-contained in one place that can easily be swapped out for one of the new extensions.

      Spend half an hour rewriting this module to use one of the other, more modern, extensions; test thoroughly. You can later introduce further refinements to reap the rewards of the benefits they offer.

    • The database access methods are scattered all over the place and cannot easily be swapped out for one of the new extensions.

      Consider whether you really need to upgrade to PHP v5.5 at this time.

      You should begin planning to replace ext/mysql with one of the other, more modern, extensions in order that you can reap the rewards of the benefits they offer; you might also use it as an opportunity to refactor your database access methods into a more modular structure.

      However, if you have an urgent need to upgrade PHP right away, you might consider suppressing deprecation errors for the time being: but first be sure to identify any other deprecation errors that are also being thrown.

  • You are using a third party project that depends upon ext/mysql.

    Consider whether you really need to upgrade to PHP v5.5 at this time.

    Check whether the developer has released any fixes, workarounds or guidance in relation to this specific issue; or, if not, pressure them to do so by bringing this matter to their attention. If you have an urgent need to upgrade PHP right away, you might consider suppressing deprecation errors for the time being: but first be sure to identify any other deprecation errors that are also being thrown.

    It is absolutely essential to perform regression testing.

How to change Screen buffer size in Windows Command Prompt from batch script

Here's what I did in case someone finds it useful (I used a lot of things according to the rest of the answers in this thread):

First I adjusted the layout settings as needed. This changes the window size immediately so it was easier to set the exact size that I wanted. By the way I didn't know that I can also have visible width smaller than width buffer. This was nice since I usually hate a long line to be wrapped. enter image description here

Then after clicking ok, I opened regedit.exe and went to "HKEY_CURRENT_USER\Console". There is a new child entry there "%SystemRoot%_system32_cmd.exe". I right clicked on that and selected Export: enter image description here

I saved this as "cmd_settings.reg". Then I created a batch script that imports those settings, invokes my original batch script (name batch_script.bat) and then deletes what I imported in order for the command line window to return to default settings:

regedit /s cmd_settings.reg
start /wait batch_script.bat
reg delete "HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe" /f

This is a sample batch that could be invoked ("batch_script.bat"):

@echo off
echo test!
pause
exit

Don't forget the exit command at the end of your script if you want the reg delete line to run after the script execution.

How do I use the lines of a file as arguments of a command?

As already mentioned, you can use the backticks or $(cat filename).

What was not mentioned, and I think is important to note, is that you must remember that the shell will break apart the contents of that file according to whitespace, giving each "word" it finds to your command as an argument. And while you may be able to enclose a command-line argument in quotes so that it can contain whitespace, escape sequences, etc., reading from the file will not do the same thing. For example, if your file contains:

a "b c" d

the arguments you will get are:

a
"b
c"
d

If you want to pull each line as an argument, use the while/read/do construct:

while read i ; do command_name $i ; done < filename

Use RSA private key to generate public key?

The Public Key is not stored in the PEM file as some people think. The following DER structure is present on the Private Key File:

openssl rsa -text -in mykey.pem

RSAPrivateKey ::= SEQUENCE {
  version           Version,
  modulus           INTEGER,  -- n
  publicExponent    INTEGER,  -- e
  privateExponent   INTEGER,  -- d
  prime1            INTEGER,  -- p
  prime2            INTEGER,  -- q
  exponent1         INTEGER,  -- d mod (p-1)
  exponent2         INTEGER,  -- d mod (q-1)
  coefficient       INTEGER,  -- (inverse of q) mod p
  otherPrimeInfos   OtherPrimeInfos OPTIONAL
}

So there is enough data to calculate the Public Key (modulus and public exponent), which is what openssl rsa -in mykey.pem -pubout does

What is the equivalent of Java's final in C#?

As mentioned, sealed is an equivalent of final for methods and classes.

As for the rest, it is complicated.

  • For static final fields, static readonly is the closest thing possible. It allows you to initialize the static field in a static constructor, which is fairly similar to static initializer in Java. This applies both to constants (primitives and immutable objects) and constant references to mutable objects.

    The const modifier is fairly similar for constants, but you can't set them in a static constructor.

  • On a field that shouldn't be reassigned once it leaves the constructor, readonly can be used. It is not equal though - final requires exactly one assignment even in constructor or initializer.

  • There is no C# equivalent for a final local variable that I know of. If you are wondering why would anyone need it: You can declare a variable prior to an if-else, switch-case or so. By declaring it final, you enforce that it is assigned at most once.

    Java local variables in general are required to be assigned at least once before they are read. Unless the branch jumps out before value read, a final variable is assigned exactly once. All of this is checked compile-time. This requires well behaved code with less margin for an error.

Summed up, C# has no direct equivalent of final. While Java lacks some nice features of C#, it is refreshing for me as mostly a Java programmer to see where C# fails to deliver an equivalent.

Best way to test if a row exists in a MySQL table

I'd go with COUNT(1). It is faster than COUNT(*) because COUNT(*) tests to see if at least one column in that row is != NULL. You don't need that, especially because you already have a condition in place (the WHERE clause). COUNT(1) instead tests the validity of 1, which is always valid and takes a lot less time to test.

How does MySQL process ORDER BY and LIMIT in a query?

The LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).

With two arguments, the first argument specifies the offset of the first row to return, and the second specifies the maximum number of rows to return. The offset of the initial row is 0 (not 1):

SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15

To retrieve all rows from a certain offset up to the end of the result set, you can use some large number for the second parameter. This statement retrieves all rows from the 96th row to the last:

SELECT * FROM tbl LIMIT 95,18446744073709551615;

With one argument, the value specifies the number of rows to return from the beginning of the result set:

SELECT * FROM tbl LIMIT 5; # Retrieve first 5 rows

In other words, LIMIT row_count is equivalent to LIMIT 0, row_count.

All details on: http://dev.mysql.com/doc/refman/5.0/en/select.html

Adding rows to dataset

To add rows to existing DataTable in Dataset:

DataRow drPartMtl = DSPartMtl.Tables[0].NewRow();
drPartMtl["Group"] = "Group";
drPartMtl["BOMPart"] = "BOMPart";
DSPartMtl.Tables[0].Rows.Add(drPartMtl);

Single quotes vs. double quotes in Python

I just use whatever strikes my fancy at the time; it's convenient to be able to switch between the two at a whim!

Of course, when quoting quote characetrs, switching between the two might not be so whimsical after all...

How to enable Google Play App Signing

While Migrating Android application package file (APK) to Android App Bundle (AAB), publishing app into Play Store i faced this issue and got resolved like this below...

When building .aab file you get prompted for the location to store key export path as below:

enter image description here
enter image description here In second image you find Encrypted key export path Location where our .pepk will store in the specific folder while generating .aab file.

Once you log in to the Google Play Console with play store credential: select your project from left side choose App Signing option Release Management>>App Signing enter image description here

you will find the Google App Signing Certification window ACCEPT it.

After that you will find three radio button select **

Upload a key exported from Android Studio radio button

**, it will expand you APP SIGNING PRIVATE KEY button as below

enter image description here

click on the button and choose the .pepk file (We Stored while generating .aab file as above)

Read the all other option and submit.

Once Successfully you can go back to app release and browse the .aab file and complete RollOut...

@Ambilpura

Eclipse/Java code completion not working

Just in case anyone got to a desperate point where nothing works... It happened to us that the content assist somehow shrunk so no suggestion was shown, just the "Press Ctrl+Space for non-Java..." could be seen. So, it was just a matter of dragging the corner of the content assist to enlarge the pop-up.

I know, embarrassing. Hope it helps.

Note: this was an Ubuntu server with Xfce4 using Eclipse Oxygen.

How do I detect a click outside an element?

I did it like this in YUI 3:

// Detect the click anywhere other than the overlay element to close it.
Y.one(document).on('click', function (e) {
    if (e.target.ancestor('#overlay') === null && e.target.get('id') != 'show' && overlay.get('visible') == true) {
        overlay.hide();
    }
});

I am checking if ancestor is not the widget element container,
if target is not which open the widget/element,
if widget/element I want to close is already open (not that important).

What is path of JDK on Mac ?

On my Mac:

/System/Library/Frameworks/JavaVM.framework/Home/

btw, did you tried which java?

How do you list all triggers in a MySQL database?

You can use below to find a particular trigger definition.

SHOW TRIGGERS LIKE '%trigger_name%'\G

or the below to show all the triggers in the database. It will work for MySQL 5.0 and above.

SHOW TRIGGERS\G

Pass variables by reference in JavaScript

  1. primitive type variables like strings and numbers are always passed by value.
  2. Arrays and Objects are passed by reference or by value based on these conditions:

    • if you are setting the value of an object or array it is Pass by Value.

      object1 = {prop: "car"}; array1 = [1,2,3];

    • if you are changing a property value of an object or array then it is Pass by Reference.

      object1.prop = "car"; array1[0] = 9;

Code

_x000D_
_x000D_
function passVar(obj1, obj2, num) {_x000D_
    obj1.prop = "laptop"; // will CHANGE original_x000D_
    obj2 = { prop: "computer" }; //will NOT affect original_x000D_
    num = num + 1; // will NOT affect original_x000D_
}_x000D_
_x000D_
var object1 = {_x000D_
    prop: "car"_x000D_
};_x000D_
var object2 = {_x000D_
    prop: "bike"_x000D_
};_x000D_
var number1 = 10;_x000D_
_x000D_
passVar(object1, object2, number1);_x000D_
console.log(object1); //output: Object {item:"laptop"}_x000D_
console.log(object2); //output: Object {item:"bike"}_x000D_
console.log(number1); //ouput: 10
_x000D_
_x000D_
_x000D_

MySQL Incorrect datetime value: '0000-00-00 00:00:00'

SET sql_mode = 'NO_ZERO_DATE';
UPDATE `news` SET `d_stop`='2038-01-01 00:00:00' WHERE `d_stop`='0000-00-00 00:00:00'

How to get the IP address of the docker host from inside a docker container

The --add-host could be a more cleaner solution (but without the port part, only the host can be handled with this solution). So, in your docker run command, do something like:

docker run --add-host dockerhost:`/sbin/ip route|awk '/default/ { print  $3}'` [my container]

(From https://stackoverflow.com/a/26864854/127400 )

How to efficiently count the number of keys/properties of an object in JavaScript?

You can use:

Object.keys(objectName).length; 

and

Object.values(objectName).length;

Android YouTube app Play Video Intent

You can also just grab the WebViewClient

wvClient = new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
  if (url.startsWith("youtube:")) {
    String youtubeUrl = "http://www.youtube.com/watch?v="
    + url.Replace("youtube:", "");
  startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(youtubeUrl)));
}
return false;
}

Worked fine in my app.

MySQL combine two columns and add into a new column

Are you sure you want to do this? In essence, you're duplicating the data that is in the three original columns. From that point on, you'll need to make sure that the data in the combined field matches the data in the first three columns. This is more overhead for your application, and other processes that update the system will need to understand the relationship.

If you need the data, why not select in when you need it? The SQL for selecting what would be in that field would be:

SELECT CONCAT(zipcode, ' - ', city, ', ', state) FROM Table;

This way, if the data in the fields changes, you don't have to update your combined field.

Can we install Android OS on any Windows Phone and vice versa, and same with iPhone and vice versa?

Ok, For installing Android on Windows phone, I think you can..(But your window phone has required configuration to run Android) (For other I don't know If I will then surely post here)

Just go through these links,

Run Android on Your Windows Mobile Phone

full tutorial on how to put android on windows mobile touch pro 2

How to install Android on most Windows Mobile phones

Update:

For Windows 7 to Android device, this also possible, (You need to do some hack for this)

Just go through these links,

Install Windows Phone 7 Mango on HTC HD2 [How-To Guide]

HTC HD2: How To Install WP7 (Windows Phone 7) & MAGLDR 1.13 To NAND

Install windows phone 7 on android and iphones | Tips and Tricks

How to install Windows Phone 7 on HTC HD2? (Video)


To Install Android on your iOS Devices (This also possible...)

Look at How To Install Android on your iOS Devices

Android 2.2 Froyo running on Iphone

How to paste text to end of every line? Sublime 2

Yeah Regex is cool, but there are other alternative.

  • Select all the lines you want to prefix or suffix
  • Goto menu Selection -> Split into Lines (Cmd/Ctrl + Shift + L)

This allows you to edit multiple lines at once. Now you can add *Quotes (") or anything * at start and end of each lines.

Proper way to catch exception from JSON.parse

You can try this:

Promise.resolve(JSON.parse(response)).then(json => {
    response = json ;
}).catch(err => {
    response = response
});

Preventing twitter bootstrap carousel from auto sliding on page load

Or if you're using Bootstrap 3.0 you can stop the cycling with data-interval="false" for instance

<div id="carousel-example-generic" class="carousel slide" data-interval="false">

Other helpful carousel data attributes are here -> http://getbootstrap.com/javascript/#carousel-usage

VSCode single to double quote automatic replace

Well for me both options solved the issue:

  1. By adding inside the .prettierrc - "singleQuote": true

  2. Or by adding following inside the package.json -> "prettier": { "singleQuote": true }

Though I tried also adding .prettierrc.js and have following

module.exports = { singleQuote: true };

This didn't worked.

ReactJs: What should the PropTypes be for this.props.children?

Example:

import React from 'react';
import PropTypes from 'prop-types';

class MenuItem extends React.Component {
    render() {
        return (
            <li>
                <a href={this.props.href}>{this.props.children}</a>
            </li>
        );
    }
}

MenuItem.defaultProps = {
    href: "/",
    children: "Main page"
};

MenuItem.propTypes = {
    href: PropTypes.string.isRequired,
    children: PropTypes.string.isRequired
};

export default MenuItem;

Picture: Shows you error in console if the expected type is different

Picture: Shows you error in console if the expected type is different

SignalR Console app example

First of all, you should install SignalR.Host.Self on the server application and SignalR.Client on your client application by nuget :

PM> Install-Package SignalR.Hosting.Self -Version 0.5.2

PM> Install-Package Microsoft.AspNet.SignalR.Client

Then add the following code to your projects ;)

(run the projects as administrator)

Server console app:

using System;
using SignalR.Hubs;

namespace SignalR.Hosting.Self.Samples {
    class Program {
        static void Main(string[] args) {
            string url = "http://127.0.0.1:8088/";
            var server = new Server(url);

            // Map the default hub url (/signalr)
            server.MapHubs();

            // Start the server
            server.Start();

            Console.WriteLine("Server running on {0}", url);

            // Keep going until somebody hits 'x'
            while (true) {
                ConsoleKeyInfo ki = Console.ReadKey(true);
                if (ki.Key == ConsoleKey.X) {
                    break;
                }
            }
        }

        [HubName("CustomHub")]
        public class MyHub : Hub {
            public string Send(string message) {
                return message;
            }

            public void DoSomething(string param) {
                Clients.addMessage(param);
            }
        }
    }
}

Client console app:

using System;
using SignalR.Client.Hubs;

namespace SignalRConsoleApp {
    internal class Program {
        private static void Main(string[] args) {
            //Set connection
            var connection = new HubConnection("http://127.0.0.1:8088/");
            //Make proxy to hub based on hub name on server
            var myHub = connection.CreateHubProxy("CustomHub");
            //Start connection

            connection.Start().ContinueWith(task => {
                if (task.IsFaulted) {
                    Console.WriteLine("There was an error opening the connection:{0}",
                                      task.Exception.GetBaseException());
                } else {
                    Console.WriteLine("Connected");
                }

            }).Wait();

            myHub.Invoke<string>("Send", "HELLO World ").ContinueWith(task => {
                if (task.IsFaulted) {
                    Console.WriteLine("There was an error calling send: {0}",
                                      task.Exception.GetBaseException());
                } else {
                    Console.WriteLine(task.Result);
                }
            });

            myHub.On<string>("addMessage", param => {
                Console.WriteLine(param);
            });

            myHub.Invoke<string>("DoSomething", "I'm doing something!!!").Wait();


            Console.Read();
            connection.Stop();
        }
    }
}

How to clear gradle cache?

UPDATE

cleanBuildCache no longer works.

Android Gradle plugin now utilizes Gradle cache feature
https://guides.gradle.org/using-build-cache/

TO CLEAR CACHE

Clean the cache directory to avoid any hits from previous builds

 rm -rf $GRADLE_HOME/caches/build-cache-*

https://guides.gradle.org/using-build-cache/#caching_android_projects

Other digressions: see here (including edits).


=== OBSOLETE INFO ===

Newest solution using Gradle task:

cleanBuildCache

Available via Android plugin for Gradle, revision 2.3.0 (February 2017)

Dependencies:

  1. Gradle 3.3 or higher.
  2. Build Tools 25.0.0 or higher.

More info at:
https://developer.android.com/studio/build/build-cache.html#clear_the_build_cache

Background

Build cache
Stores certain outputs that the Android plugin generates when building your project (such as unpackaged AARs and pre-dexed remote dependencies). Your clean builds are much faster while using the cache because the build system can simply reuse those cached files during subsequent builds, instead of recreating them. Projects using Android plugin 2.3.0 and higher use the build cache by default. To learn more, read Improve Build Speed with Build Cache.

NOTE: The cleanBuildCache task is not available if you disable the build cache.


USAGE

Windows:

gradlew cleanBuildCache

Linux / Mac:

gradle cleanBuildCache

Android Studio / IntelliJ:

gradle tab (default on right) select and run the task or add it via the configuration window 

NOTE: gradle / gradlew are system specific files containing scripts. Please see the related system info how to execute the scripts:

Real world use of JMS/message queues?

JMS (ActiveMQ is a JMS broker implementation) can be used as a mechanism to allow asynchronous request processing. You may wish to do this because the request take a long time to complete or because several parties may be interested in the actual request. Another reason for using it is to allow multiple clients (potentially written in different languages) to access information via JMS. ActiveMQ is a good example here because you can use the STOMP protocol to allow access from a C#/Java/Ruby client.

A real world example is that of a web application that is used to place an order for a particular customer. As part of placing that order (and storing it in a database) you may wish to carry a number of additional tasks:

  • Store the order in some sort of third party back-end system (such as SAP)
  • Send an email to the customer to inform them their order has been placed

To do this your application code would publish a message onto a JMS queue which includes an order id. One part of your application listening to the queue may respond to the event by taking the orderId, looking the order up in the database and then place that order with another third party system. Another part of your application may be responsible for taking the orderId and sending a confirmation email to the customer.

Converting a double to an int in C#

you can round your double and cast ist:

(int)Math.Round(myDouble);

J2ME/Android/BlackBerry - driving directions, route between two locations

J2ME Map Route Provider

maps.google.com has a navigation service which can provide you route information in KML format.

To get kml file we need to form url with start and destination locations:

public static String getUrl(double fromLat, double fromLon,
                            double toLat, double toLon) {// connect to map web service
    StringBuffer urlString = new StringBuffer();
    urlString.append("http://maps.google.com/maps?f=d&hl=en");
    urlString.append("&saddr=");// from
    urlString.append(Double.toString(fromLat));
    urlString.append(",");
    urlString.append(Double.toString(fromLon));
    urlString.append("&daddr=");// to
    urlString.append(Double.toString(toLat));
    urlString.append(",");
    urlString.append(Double.toString(toLon));
    urlString.append("&ie=UTF8&0&om=0&output=kml");
    return urlString.toString();
}

Next you will need to parse xml (implemented with SAXParser) and fill data structures:

public class Point {
    String mName;
    String mDescription;
    String mIconUrl;
    double mLatitude;
    double mLongitude;
}

public class Road {
    public String mName;
    public String mDescription;
    public int mColor;
    public int mWidth;
    public double[][] mRoute = new double[][] {};
    public Point[] mPoints = new Point[] {};
}

Network connection is implemented in different ways on Android and Blackberry, so you will have to first form url:

 public static String getUrl(double fromLat, double fromLon,
     double toLat, double toLon)

then create connection with this url and get InputStream.
Then pass this InputStream and get parsed data structure:

 public static Road getRoute(InputStream is) 

Full source code RoadProvider.java

BlackBerry

class MapPathScreen extends MainScreen {
    MapControl map;
    Road mRoad = new Road();
    public MapPathScreen() {
        double fromLat = 49.85, fromLon = 24.016667;
        double toLat = 50.45, toLon = 30.523333;
        String url = RoadProvider.getUrl(fromLat, fromLon, toLat, toLon);
        InputStream is = getConnection(url);
        mRoad = RoadProvider.getRoute(is);
        map = new MapControl();
        add(new LabelField(mRoad.mName));
        add(new LabelField(mRoad.mDescription));
        add(map);
    }
    protected void onUiEngineAttached(boolean attached) {
        super.onUiEngineAttached(attached);
        if (attached) {
            map.drawPath(mRoad);
        }
    }
    private InputStream getConnection(String url) {
        HttpConnection urlConnection = null;
        InputStream is = null;
        try {
            urlConnection = (HttpConnection) Connector.open(url);
            urlConnection.setRequestMethod("GET");
            is = urlConnection.openInputStream();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return is;
    }
}

See full code on J2MEMapRouteBlackBerryEx on Google Code

Android

Android G1 screenshot

public class MapRouteActivity extends MapActivity {
    LinearLayout linearLayout;
    MapView mapView;
    private Road mRoad;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        mapView = (MapView) findViewById(R.id.mapview);
        mapView.setBuiltInZoomControls(true);
        new Thread() {
            @Override
            public void run() {
                double fromLat = 49.85, fromLon = 24.016667;
                double toLat = 50.45, toLon = 30.523333;
                String url = RoadProvider
                        .getUrl(fromLat, fromLon, toLat, toLon);
                InputStream is = getConnection(url);
                mRoad = RoadProvider.getRoute(is);
                mHandler.sendEmptyMessage(0);
            }
        }.start();
    }

    Handler mHandler = new Handler() {
        public void handleMessage(android.os.Message msg) {
            TextView textView = (TextView) findViewById(R.id.description);
            textView.setText(mRoad.mName + " " + mRoad.mDescription);
            MapOverlay mapOverlay = new MapOverlay(mRoad, mapView);
            List<Overlay> listOfOverlays = mapView.getOverlays();
            listOfOverlays.clear();
            listOfOverlays.add(mapOverlay);
            mapView.invalidate();
        };
    };

    private InputStream getConnection(String url) {
        InputStream is = null;
        try {
            URLConnection conn = new URL(url).openConnection();
            is = conn.getInputStream();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return is;
    }
    @Override
    protected boolean isRouteDisplayed() {
        return false;
    }
}

See full code on J2MEMapRouteAndroidEx on Google Code

Find and replace specific text characters across a document with JS

Vanilla JavaScript solution:

document.body.innerHTML = document.body.innerHTML.replace(/Original/g, "New")

Limiting double to 3 decimal places

In C lang:

double truncKeepDecimalPlaces(double value, int numDecimals)
{
    int x = pow(10, numDecimals);
    return (double)trunc(value * x) / x;
}

Proper way to wait for one function to finish before continuing?

The only issue with promises is that IE doesn't support them. Edge does, but there's plenty of IE 10 and 11 out there: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise (compatibility at the bottom)

So, JavaScript is single-threaded. If you're not making an asynchronous call, it will behave predictably. The main JavaScript thread will execute one function completely before executing the next one, in the order they appear in the code. Guaranteeing order for synchronous functions is trivial - each function will execute completely in the order it was called.

Think of the synchronous function as an atomic unit of work. The main JavaScript thread will execute it fully, in the order the statements appear in the code.

But, throw in the asynchronous call, as in the following situation:

showLoadingDiv(); // function 1

makeAjaxCall(); // function 2 - contains async ajax call

hideLoadingDiv(); // function 3

This doesn't do what you want. It instantaneously executes function 1, function 2, and function 3. Loading div flashes and it's gone, while the ajax call is not nearly complete, even though makeAjaxCall() has returned. THE COMPLICATION is that makeAjaxCall() has broken its work up into chunks which are advanced little by little by each spin of the main JavaScript thread - it's behaving asychronously. But that same main thread, during one spin/run, executed the synchronous portions quickly and predictably.

So, the way I handled it: Like I said the function is the atomic unit of work. I combined the code of function 1 and 2 - I put the code of function 1 in function 2, before the asynch call. I got rid of function 1. Everything up to and including the asynchronous call executes predictably, in order.

THEN, when the asynchronous call completes, after several spins of the main JavaScript thread, have it call function 3. This guarantees the order. For example, with ajax, the onreadystatechange event handler is called multiple times. When it reports it's completed, then call the final function you want.

I agree it's messier. I like having code be symmetric, I like having functions do one thing (or close to it), and I don't like having the ajax call in any way be responsible for the display (creating a dependency on the caller). BUT, with an asynchronous call embedded in a synchronous function, compromises have to be made in order to guarantee order of execution. And I have to code for IE 10 so no promises.

Summary: For synchronous calls, guaranteeing order is trivial. Each function executes fully in the order it was called. For a function with an asynchronous call, the only way to guarantee order is to monitor when the async call completes, and call the third function when that state is detected.

For a discussion of JavaScript threads, see: https://medium.com/@francesco_rizzi/javascript-main-thread-dissected-43c85fce7e23 and https://developer.mozilla.org/en-US/docs/Web/JavaScript/EventLoop

Also, another similar, highly rated question on this subject: How should I call 3 functions in order to execute them one after the other?

How do I change the default port (9000) that Play uses when I execute the "run" command?

We cannot change the application port from the avtivator but can change from the command line activator "~run 8080"

But to run on the poet 9000 from the activator we need to stop the application which is using this port. We can use the this application to find this and end the process https://technet.microsoft.com/en-in/sysinternals/bb897437.aspx

After this we can run and it will be successful.

Comments in Android Layout xml

The World Wide Web Consortium (W3C) actually defined a comment interface. The definition says all the characters between the starting ' <!--' and ending '-->' form a part of comment content and no lexical check is done on the content of a comment.

More details are available on developer.android.com site.

So you can simply add your comment in between any starting and ending tag. In Eclipse IDE simply typing <!-- would auto complete the comment for you. You can then add your comment text in between.

For example:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    tools:context=".TicTacToe" >

 <!-- This is a comment -->

</LinearLayout>

Purpose of specifically mentioning in between is because you cannot use it inside a tag.

For example:

<TextView 
    android:text="@string/game_title"
    <!-- This is a comment -->
    android:layout_height="wrap_content"
    android:layout_width="fill_parent"/>

is wrong and will give following error

 Element type "TextView" must be followed by either attribute specifications, ">" or "/>".

Difference between mkdir() and mkdirs() in java for java.io.File

mkdirs() also creates parent directories in the path this File represents.

javadocs for mkdirs():

Creates the directory named by this abstract pathname, including any necessary but nonexistent parent directories. Note that if this operation fails it may have succeeded in creating some of the necessary parent directories.

javadocs for mkdir():

Creates the directory named by this abstract pathname.

Example:

File  f = new File("non_existing_dir/someDir");
System.out.println(f.mkdir());
System.out.println(f.mkdirs());

will yield false for the first [and no dir will be created], and true for the second, and you will have created non_existing_dir/someDir

How to Use Multiple Columns in Partition By And Ensure No Duplicate Row is Returned

I'd create a cte and do an inner join. It's not efficient but it's convenient

with table as (
SELECT DATE, STATUS, TITLE, ROW_NUMBER() 
OVER (PARTITION BY DATE, STATUS,  TITLE ORDER BY QUANTITY ASC) AS Row_Num
 FROM TABLE)

select *

from table t
join select(
max(Row_Num) as Row_Num
,DATE
,STATUS
,TITLE
from table 
group by date, status, title) t2  
on t2.Row_Num = t.Row_Num and t2
and t2.date = t.date
and t2.title = t.title

How to replace blank (null ) values with 0 for all records?

UPDATE YourTable SET MyField = 0 WHERE MyField IS NULL

works in most SQL dialects. I don't use Access, but that should get you started.

How to declare a global variable in C++

Not sure if this is correct in any sense but this seems to work for me.

someHeader.h
inline int someVar;

I don't have linking/multiple definition issues and it "just works"... ;- )

It's quite handy for "quick" tests... Try to avoid global vars tho, because every says so... ;- )

mysql alphabetical order

You do not need to user where clause while ordering the data alphabetically. here is my code

SELECT * FROM tbl_name ORDER BY field_name

that's it. It return the data in alphabetical order ie; From A to Z. :)

How do I assign ls to an array in Linux Bash?

Whenever possible, you should avoid parsing the output of ls (see Greg's wiki on the subject). Basically, the output of ls will be ambiguous if there are funny characters in any of the filenames. It's also usually a waste of time. In this case, when you execute ls -d */, what happens is that the shell expands */ to a list of subdirectories (which is already exactly what you want), passes that list as arguments to ls -d, which looks at each one, says "yep, that's a directory all right" and prints it (in an inconsistent and sometimes ambiguous format). The ls command isn't doing anything useful!

Well, ok, it is doing one thing that's useful: if there are no subdirectories, */ will get left as is, ls will look for a subdirectory named "*", not find it, print an error message that it doesn't exist (to stderr), and not print the "*/" (to stdout).

The cleaner way to make an array of subdirectory names is to use the glob (*/) without passing it to ls. But in order to avoid putting "*/" in the array if there are no actual subdirectories, you should set nullglob first (again, see Greg's wiki):

shopt -s nullglob
array=(*/)
shopt -u nullglob # Turn off nullglob to make sure it doesn't interfere with anything later
echo "${array[@]}"  # Note double-quotes to avoid extra parsing of funny characters in filenames

If you want to print an error message if there are no subdirectories, you're better off doing it yourself:

if (( ${#array[@]} == 0 )); then
    echo "No subdirectories found" >&2
fi

How to gracefully handle the SIGKILL signal in Java

It is impossible for any program, in any language, to handle a SIGKILL. This is so it is always possible to terminate a program, even if the program is buggy or malicious. But SIGKILL is not the only means for terminating a program. The other is to use a SIGTERM. Programs can handle that signal. The program should handle the signal by doing a controlled, but rapid, shutdown. When a computer shuts down, the final stage of the shutdown process sends every remaining process a SIGTERM, gives those processes a few seconds grace, then sends them a SIGKILL.

The way to handle this for anything other than kill -9 would be to register a shutdown hook. If you can use (SIGTERM) kill -15 the shutdown hook will work. (SIGINT) kill -2 DOES cause the program to gracefully exit and run the shutdown hooks.

Registers a new virtual-machine shutdown hook.

The Java virtual machine shuts down in response to two kinds of events:

  • The program exits normally, when the last non-daemon thread exits or when the exit (equivalently, System.exit) method is invoked, or
  • The virtual machine is terminated in response to a user interrupt, such as typing ^C, or a system-wide event, such as user logoff or system shutdown.

I tried the following test program on OSX 10.6.3 and on kill -9 it did NOT run the shutdown hook, as expected. On a kill -15 it DOES run the shutdown hook every time.

public class TestShutdownHook
{
    public static void main(String[] args) throws InterruptedException
    {
        Runtime.getRuntime().addShutdownHook(new Thread()
        {
            @Override
            public void run()
            {
                System.out.println("Shutdown hook ran!");
            }
        });

        while (true)
        {
            Thread.sleep(1000);
        }
    }
}

There isn't any way to really gracefully handle a kill -9 in any program.

In rare circumstances the virtual machine may abort, that is, stop running without shutting down cleanly. This occurs when the virtual machine is terminated externally, for example with the SIGKILL signal on Unix or the TerminateProcess call on Microsoft Windows.

The only real option to handle a kill -9 is to have another watcher program watch for your main program to go away or use a wrapper script. You could do with this with a shell script that polled the ps command looking for your program in the list and act accordingly when it disappeared.

#!/usr/bin/env bash

java TestShutdownHook
wait
# notify your other app that you quit
echo "TestShutdownHook quit"

Is it possible to write to the console in colour in .NET?

Yes, it's easy and possible. Define first default colors.

Console.BackgroundColor = ConsoleColor.Black;
Console.ForegroundColor = ConsoleColor.White;
Console.Clear();

Console.Clear() it's important in order to set new console colors. If you don't make this step you can see combined colors when ask for values with Console.ReadLine().

Then you can change the colors on each print:

Console.BackgroundColor = ConsoleColor.Black;
Console.ForegroundColor = ConsoleColor.Red;
Console.WriteLine("Red text over black.");

When finish your program, remember reset console colors on finish:

Console.ResetColor();
Console.Clear();

Now with netcore we have another problem if you want to "preserve" the User experience because terminal have different colors on each Operative System.

I'm making a library that solves this problem with Text Format: colors, alignment and lot more. Feel free to use and contribute.

https://github.com/deinsoftware/colorify/ and also available as NuGet package

Colors for Windows/Linux (Dark):
enter image description here

Colors for MacOS (Light):
enter image description here

Migrating from VMWARE to VirtualBox

After many attempts I was finally able to get this working. Essentially what I did was download and use the vmware converter to merge the two disks into one. After that I was able to attach the newly created disk to VitrualBox.

The steps involved are very simple:

BEFORE YOU DO ANYTHING!

1) MAKE A BACKUP!!! Even if you follow these instruction, you could screw things up, so make a backup. Just shutdown the VM and then make a copy of the directory where VM resides.

2) Uninstall VMware Tools from the VM that you are going to convert. If for some reason you forget this step, you can still uninstall it after getting everything running under VirtualBox by following these steps. Do yourself the favor and just do it now.

NOW THE FUN PART!!!

1) Download and install the VMware Converter. I used 5.0.1 build-875114, just use the latest.

2) Download and install VirtualBox

3) Fire up VMWare convertor:

Fire up VMWare convertor

4) Click on Convert machine

6) Browse to the .vmx for your VM and click Next.

Convert machine

7) Give the new VM a name and select the location where you want to put it. Click Next

Give the new VM a name and select the location

8) Click Next on the Options screen. You shouldn't have to change anything here.

Click <code>Next</code> on the <code>Options</code> screen.

9) Click Finish on the Summary screen to begin the conversion.

Click <code>Finish</code> on the <code>Summary</code> screen

10) The conversion should start. This will take a LOOONG time so be patient.

The conversion should start.

11) Hopefully all went well, if it did, you should see that the conversion is completed:

conversion is completed

12) Now open up VirtualBox and click New.

open up VirtualBox and click <code>New</code>

13) Give your VM a name and select what Type and Version it is. Click Next.

Give your VM a name and select what <code>Type</code> and <code>Version</code> it is.

14) Select the size of the memory you want to give it. Click Next.

Select the size of the memory you want to give it.

15) For the Hard Drive, click Use and existing hard drive file and select the newly converted .vmdk file.

Use and existing hard drive file

16) Now Click Settings and select the Storage menu. The issue is that by default VirtualBox will add the drive as an IDE. This won't work and we need as we need to put it on a SCSI controller.

put it on a SCSI controller

17) Select the IDE controller and the Remove Controller button.

Select the IDE controller and the <code>Remove Controller</code> button.

18) Now click the Add Controller button and select Add SCSI Controller

Add SCSI Controller

19) Click the Add Hard Disk button.

Add Hard Disk

20) Click Choose existing disk

Choose existing disk

21) Select your .vmdk file. Click OK

Select your <code>.vmdk</code> file.

22) Select the System menu.

Select the <code>System</code> menu.

23) Click Enable IO APIC. Then click OK

Click <code>Enable IO APIC</code>.

24) Congrats!!! Your VM is now confgiured! Click Start to startup the VM!

Click <code>Start</code> to startup the VM!

Android WebView, how to handle redirects in app instead of opening a browser

Create a WebViewClient, and override the shouldOverrideUrlLoading method.

webview.setWebViewClient(new WebViewClient() {
    public boolean shouldOverrideUrlLoading(WebView view, String url){
        // do your handling codes here, which url is the requested url
        // probably you need to open that url rather than redirect:
        view.loadUrl(url);
        return false; // then it is not handled by default action
   }
});

Pandas DataFrame to List of Lists

I wanted to preserve the index, so I adapted the original answer to this solution:

list_df = df.reset_index().values.tolist()

Now you can paste it somewhere else (e.g. to paste into a Stack Overflow question) and latter recreate it:

pd.Dataframe(list_df, columns=['name1', ...])
pd.set_index(['name1'], inplace=True)

PHP, display image with Header()

There is a better why to determine type of an image. with exif_imagetype

If you use this function, you can tell image's real extension.

with this function filename's extension is completely irrelevant, which is good.

function setHeaderContentType(string $filePath): void
{
    $numberToContentTypeMap = [
        '1' => 'image/gif',
        '2' => 'image/jpeg',
        '3' => 'image/png',
        '6' => 'image/bmp',
        '17' => 'image/ico'
    ];

    $contentType = $numberToContentTypeMap[exif_imagetype($filePath)] ?? null;
    
    if ($contentType === null) {
        throw new Exception('Unable to determine content type of file.');
    }

    header("Content-type: $contentType");
}

You can add more types from the link.

Hope it helps.

Page scroll when soft keyboard popped up

You can try using the following code to solve your problem:

 <activity
     android:name=".DonateNow"
     android:label="@string/title_activity_donate_now"
     android:screenOrientation="portrait"
     android:theme="@style/AppTheme"
     android:windowSoftInputMode="stateVisible|adjustPan">
 </activity>

UnicodeDecodeError: 'charmap' codec can't decode byte X in position Y: character maps to <undefined>

Stop wasting your time, just add the following encoding="cp437" and errors='ignore' to your code in both read and write:

open('filename.csv', encoding="cp437", errors='ignore')
open(file_name, 'w', newline='', encoding="cp437", errors='ignore')

Godspeed

How to run a function in jquery

The following should work nicely.

$(function() {

  // Way 1
  function doosomething()
  {
    //Doo something
  }

  // Way 2, equivalent to Way 1
  var doosomething = function() {
    // Doo something
  }

  $("div.class").click(doosomething);

  $("div.secondclass").click(doosomething);

});

Basically, you are declaring your function in the same scope as your are using it (JavaScript uses Closures to determine scope).

Now, since functions in JavaScript behave like any other object, you can simply assign doosomething as the function to call on click by using .click(doosomething);

Your function will not execute until you call it using doosomething() (doosomething without the () refers to the function but doesn't call it) or another function calls in (in this case, the click handler).

How to export a table dataframe in PySpark to csv?

If data frame fits in a driver memory and you want to save to local files system you can convert Spark DataFrame to local Pandas DataFrame using toPandas method and then simply use to_csv:

df.toPandas().to_csv('mycsv.csv')

Otherwise you can use spark-csv:

  • Spark 1.3

    df.save('mycsv.csv', 'com.databricks.spark.csv')
    
  • Spark 1.4+

    df.write.format('com.databricks.spark.csv').save('mycsv.csv')
    

In Spark 2.0+ you can use csv data source directly:

df.write.csv('mycsv.csv')

Google Maps API - Get Coordinates of address

A Nuget solved my problem:Geocoding.Google 4.0.0. Install it so not necessary to write extra classes etc.

https://www.nuget.org/packages/Geocoding.Google/

React with ES7: Uncaught TypeError: Cannot read property 'state' of undefined

Make sure you're calling super() as the first thing in your constructor.

You should set this for setAuthorState method

class ManageAuthorPage extends Component {

  state = {
    author: { id: '', firstName: '', lastName: '' }
  };

  constructor(props) {
    super(props);
    this.handleAuthorChange = this.handleAuthorChange.bind(this);
  } 

  handleAuthorChange(event) {
    let {name: fieldName, value} = event.target;

    this.setState({
      [fieldName]: value
    });
  };

  render() {
    return (
      <AuthorForm
        author={this.state.author}
        onChange={this.handleAuthorChange}
      />
    );
  }
}

Another alternative based on arrow function:

class ManageAuthorPage extends Component {

  state = {
    author: { id: '', firstName: '', lastName: '' }
  };

  handleAuthorChange = (event) => {
    const {name: fieldName, value} = event.target;

    this.setState({
      [fieldName]: value
    });
  };

  render() {
    return (
      <AuthorForm
        author={this.state.author}
        onChange={this.handleAuthorChange}
      />
    );
  }
}

How do I implement interfaces in python?

Implementing interfaces with abstract base classes is much simpler in modern Python 3 and they serve a purpose as an interface contract for plug-in extensions.

Create the interface/abstract base class:

from abc import ABC, abstractmethod

class AccountingSystem(ABC):

    @abstractmethod
    def create_purchase_invoice(self, purchase):
        pass

    @abstractmethod
    def create_sale_invoice(self, sale):
        log.debug('Creating sale invoice', sale)

Create a normal subclass and override all abstract methods:

class GizmoAccountingSystem(AccountingSystem):

    def create_purchase_invoice(self, purchase):
        submit_to_gizmo_purchase_service(purchase)

    def create_sale_invoice(self, sale):
        super().create_sale_invoice(sale)
        submit_to_gizmo_sale_service(sale)

You can optionally have common implementation in the abstract methods as in create_sale_invoice(), calling it with super() explicitly in the subclass as above.

Instantiation of a subclass that does not implement all the abstract methods fails:

class IncompleteAccountingSystem(AccountingSystem):
    pass

>>> accounting = IncompleteAccountingSystem()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: Can't instantiate abstract class IncompleteAccountingSystem with abstract methods
create_purchase_invoice, create_sale_invoice

You can also have abstract properties, static and class methods by combining corresponding annotations with @abstractmethod.

Abstract base classes are great for implementing plugin-based systems. All imported subclasses of a class are accessible via __subclasses__(), so if you load all classes from a plugin directory with importlib.import_module() and if they subclass the base class, you have direct access to them via __subclasses__() and you can be sure that the interface contract is enforced for all of them during instantiation.

Here's the plugin loading implementation for the AccountingSystem example above:

...
from importlib import import_module

class AccountingSystem(ABC):

    ...
    _instance = None

    @classmethod
    def instance(cls):
        if not cls._instance:
            module_name = settings.ACCOUNTING_SYSTEM_MODULE_NAME
            import_module(module_name)
            subclasses = cls.__subclasses__()
            if len(subclasses) > 1:
                raise InvalidAccountingSystemError('More than one '
                        f'accounting module: {subclasses}')
            if not subclasses or module_name not in str(subclasses[0]):
                raise InvalidAccountingSystemError('Accounting module '
                        f'{module_name} does not exist or does not '
                        'subclass AccountingSystem')
            cls._instance = subclasses[0]()
        return cls._instance

Then you can access the accounting system plugin object through the AccountingSystem class:

>>> accountingsystem = AccountingSystem.instance()

(Inspired by this PyMOTW-3 post.)

How do I run a Java program from the command line on Windows?

It is easy. If you have saved your file as A.text first thing you should do is save it as A.java. Now it is a Java file.

Now you need to open cmd and set path to you A.java file before compile it. you can refer this for that.

Then you can compile your file using command

javac A.java

Then run it using

java A

So that is how you compile and run a java program in cmd. You can also go through these material that is Java in depth lessons. Lot of things you need to understand in Java is covered there for beginners.

What does "both" mean in <div style="clear:both">

Both means "every item in a set of two things". The two things being "left" and "right"

How do I clear my local working directory in Git?

Use:

git clean -df

It's not well advertised, but git clean is really handy. Git Ready has a nice introduction to git clean.

Difference between "\n" and Environment.NewLine

From the docs ...

A string containing "\r\n" for non-Unix platforms, or a string containing "\n" for Unix platforms.

How to position two divs horizontally within another div

I agree with Darko Z on applying "overflow: hidden" to #sub-title. However, it should be mentioned that the overflow:hidden method of clearing floats does not work with IE6 unless you have a specified width or height. Or, if you don't want to specify a width or height, you can use "zoom: 1":

#sub-title { overflow:hidden; zoom: 1; }

WCF error - There was no endpoint listening at

You can solve the issue by clearing value of address in endpoint tag in web.config:

<endpoint address="" name="wsHttpEndpoint"  .......           />

IndexError: list index out of range and python

Yes. The sequence doesn't have the 54th item.

Set height of <div> = to height of another <div> through .css

I am assuming that you have used height attribute at both so i am comparing it with a height left do it with JavaScript.

var right=document.getElementById('rightdiv').style.height;
var left=document.getElementById('leftdiv').style.height;
if(left>right)
{
    document.getElementById('rightdiv').style.height=left;
}
else
{
    document.getElementById('leftdiv').style.height=right;
}

Another idea can be found here HTML/CSS: Making two floating divs the same height.

Passing struct to function

Instead of:

void addStudent(person)
{
    return;
}

try this:

void addStudent(student person)
{
    return;
}

Since you have already declared a structure called 'student' you don't necessarily have to specify so in the function implementation as in:

void addStudent(struct student person)
{
    return;
}

How to drop SQL default constraint without knowing its name?

Run this command to browse all constraints:

exec sp_helpconstraint 'mytable' --and look under constraint_name. 

It will look something like this: DF__Mytable__Column__[ABC123]. Then you can just drop the constraint.

How to convert image into byte array and byte array to base64 String in android?

They have wrapped most stuff need to solve your problem, one of the tests looks like this:

String filename = CSSURLEmbedderTest.class.getResource("folder.png").getPath().replace("%20", " ");
String code = "background: url(folder.png);";

StringWriter writer = new StringWriter();
embedder = new CSSURLEmbedder(new StringReader(code), true);
embedder.embedImages(writer, filename.substring(0, filename.lastIndexOf("/")+1));

String result = writer.toString();
assertEquals("background: url(" + folderDataURI + ");", result);

Get values from other sheet using VBA

Try

 ThisWorkbook.Sheets("name of sheet 2").Range("A1")

to access a range in sheet 2 independently of where your code is or which sheet is currently active. To make sheet 2 the active sheet, try

 ThisWorkbook.Sheets("name of sheet 2").Activate

If you just need the sum of a row in a different sheet, there is no need for using VBA at all. Enter a formula like this in sheet 1:

=SUM([Name-Of-Sheet2]!A1:D1)

How should I copy Strings in Java?

Since strings are immutable, both versions are safe. The latter, however, is less efficient (it creates an extra object and in some cases copies the character data).

With this in mind, the first version should be preferred.

ActionBarCompat: java.lang.IllegalStateException: You need to use a Theme.AppCompat

If you are extending ActionBarActivity in your MainActivity, you will have to change the parent theme in values-v11 also.
So the style.xml in values-v11 will be -

 <!-- res/values-v11/themes.xml -->
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
    <style name="QueryTheme" parent="@style/Theme.AppCompat">
    <!-- Any customizations for your app running on devices with Theme.Holo here -->
    </style>
 </resources>

EDIT: I would recommend you stop using ActionBar and start using the AppBar layout included in the Android Design Support Library

Get time of specific timezone

The best way to do this is to use getLocaleString, like this:

Create a date object:

date = new Date(0)

If you are in Berlin, this should convert to this string:

Thu Jan 01 1970 01:00:00 GMT+0100 (CET)

Get the hours in Athens:

date.toLocaleString('de-DE', {hour: '2-digit',   hour12: false, timeZone: 'Europe/Athens' })

'02'

Get the hours in Shanghai:

date.toLocaleString('de-DE', {hour: '2-digit',   hour12: false, timeZone: 'Asia/Shanghai' })

'08'

php pdo: get the columns name of a table

$q = $dbh->prepare("DESCRIBE tablename");
$q->execute();
$table_fields = $q->fetchAll(PDO::FETCH_COLUMN);

must be

$q = $dbh->prepare("DESCRIBE database.table");
$q->execute();
$table_fields = $q->fetchAll(PDO::FETCH_COLUMN);

How to replace all occurrences of a character in string?

For simple situations this works pretty well without using any other library then std::string (which is already in use).

Replace all occurences of character a with character b in some_string:

for (size_t i = 0; i < some_string.size(); ++i) {
    if (some_string[i] == 'a') {
        some_string.replace(i, 1, "b");
    }
}

If the string is large or multiple calls to replace is an issue, you can apply the technique mentioned in this answer: https://stackoverflow.com/a/29752943/3622300

ReactJS SyntheticEvent stopPropagation() only works with React events?

Worth noting (from this issue) that if you're attaching events to document, e.stopPropagation() isn't going to help. As a workaround, you can use window.addEventListener() instead of document.addEventListener, then event.stopPropagation() will stop event from propagating to the window.

How can I refresh a page with jQuery?

If the current page was loaded by a POST request, you may want to use

window.location = window.location.pathname;

instead of

window.location.reload();

because window.location.reload() will prompt for confirmation if called on a page that was loaded by a POST request.

Rails server says port already used, how to kill that process?

If you are on windows machine follow these steps.

c:/project/
cd tmp
c:/project/tmp
cd pids
c:/project/tmp/pids
dir

There you will a file called server.pid

delete it.

c:/project/tmp/pid> del *.pid

Thats it.

EDIT: Please refer this

How does one Display a Hyperlink in React Native App?

for the React Native, there is library to open Hyperlinks in App. https://www.npmjs.com/package/react-native-hyperlink

In addition to this, i suppose you will need to check url and best approach is Regex. https://www.npmjs.com/package/url-regex

Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist

My case on Ubuntu 14.04.2 LTS was similar to others with my.cnf, but for me the cause was a ~/.my.cnf that was leftover from a previous installation. After deleting that file and purging/re-installing mysql-server, it worked fine.

How to use an arraylist as a prepared statement parameter

You may want to use setArray method as mentioned in the javadoc below:

http://docs.oracle.com/javase/6/docs/api/java/sql/PreparedStatement.html#setArray(int, java.sql.Array)

Sample Code:

PreparedStatement pstmt = 
                conn.prepareStatement("select * from employee where id in (?)");
Array array = conn.createArrayOf("VARCHAR", new Object[]{"1", "2","3"});
pstmt.setArray(1, array);
ResultSet rs = pstmt.executeQuery();

How can I use an array of function pointers?

Oh, there are tons of example. Just have a look at anything within glib or gtk. You can see the work of function pointers in work there all the way.

Here e.g the initialization of the gtk_button stuff.


static void
gtk_button_class_init (GtkButtonClass *klass)
{
  GObjectClass *gobject_class;
  GtkObjectClass *object_class;
  GtkWidgetClass *widget_class;
  GtkContainerClass *container_class;

  gobject_class = G_OBJECT_CLASS (klass);
  object_class = (GtkObjectClass*) klass;
  widget_class = (GtkWidgetClass*) klass;
  container_class = (GtkContainerClass*) klass;

  gobject_class->constructor = gtk_button_constructor;
  gobject_class->set_property = gtk_button_set_property;
  gobject_class->get_property = gtk_button_get_property;

And in gtkobject.h you find the following declarations:


struct _GtkObjectClass
{
  GInitiallyUnownedClass parent_class;

  /* Non overridable class methods to set and get per class arguments */
  void (*set_arg) (GtkObject *object,
           GtkArg    *arg,
           guint      arg_id);
  void (*get_arg) (GtkObject *object,
           GtkArg    *arg,
           guint      arg_id);

  /* Default signal handler for the ::destroy signal, which is
   *  invoked to request that references to the widget be dropped.
   *  If an object class overrides destroy() in order to perform class
   *  specific destruction then it must still invoke its superclass'
   *  implementation of the method after it is finished with its
   *  own cleanup. (See gtk_widget_real_destroy() for an example of
   *  how to do this).
   */
  void (*destroy)  (GtkObject *object);
};

The (*set_arg) stuff is a pointer to function and this can e.g be assigned another implementation in some derived class.

Often you see something like this

struct function_table {
   char *name;
   void (*some_fun)(int arg1, double arg2);
};

void function1(int  arg1, double arg2)....


struct function_table my_table [] = {
    {"function1", function1},
...

So you can reach into the table by name and call the "associated" function.

Or maybe you use a hash table in which you put the function and call it "by name".

Regards
Friedrich

Find all paths between two graph nodes

Finding all possible paths is a hard problem, since there are exponential number of simple paths. Even finding the kth shortest path [or longest path] are NP-Hard.

One possible solution to find all paths [or all paths up to a certain length] from s to t is BFS, without keeping a visited set, or for the weighted version - you might want to use uniform cost search

Note that also in every graph which has cycles [it is not a DAG] there might be infinite number of paths between s to t.

submitting a GET form with query string params and hidden params disappear

I had a very similar problem where for the form action, I had something like:

<form action="http://www.example.com/?q=content/something" method="GET">
   <input type="submit" value="Go away..." />&nbsp;
</form>

The button would get the user to the site, but the query info disappeared so the user landed on the home page rather than the desired content page. The solution in my case was to find out how to code the URL without the query that would get the user to the desired page. In this case my target was a Drupal site, so as it turned out /content/something also worked. I also could have used a node number (i.e. /node/123).

Extend a java class from one file in another java file

What's missing from all the explanations is the fact that Java has a strict rule of class name = file name. Meaning if you have a class "Person", is must be in a file named "Person.java". Therefore, if one class tries to access "Person" the filename is not necessary, because it has got to be "Person.java".

Coming for C/C++, I have exact same issue. The answer is to create a new class (in a new file matching class name) and create a public string. This will be your "header" file. Then use that in your main file by using "extends" keyword.

Here is your answer:

  1. Create a file called Include.java. In this file, add this:

    public class Include {
        public static String MyLongString= "abcdef";
    }
    
  2. Create another file, say, User.java. In this file, put:

    import java.io.*;
    
    public class User extends Include {
        System.out.println(Include.MyLongString);
    }
    

matplotlib: colorbars and its text labels

import matplotlib.pyplot as plt
import numpy as np
from matplotlib.colors import ListedColormap

#discrete color scheme
cMap = ListedColormap(['white', 'green', 'blue','red'])

#data
np.random.seed(42)
data = np.random.rand(4, 4)
fig, ax = plt.subplots()
heatmap = ax.pcolor(data, cmap=cMap)

#legend
cbar = plt.colorbar(heatmap)

cbar.ax.get_yaxis().set_ticks([])
for j, lab in enumerate(['$0$','$1$','$2$','$>3$']):
    cbar.ax.text(.5, (2 * j + 1) / 8.0, lab, ha='center', va='center')
cbar.ax.get_yaxis().labelpad = 15
cbar.ax.set_ylabel('# of contacts', rotation=270)


# put the major ticks at the middle of each cell
ax.set_xticks(np.arange(data.shape[1]) + 0.5, minor=False)
ax.set_yticks(np.arange(data.shape[0]) + 0.5, minor=False)
ax.invert_yaxis()

#labels
column_labels = list('ABCD')
row_labels = list('WXYZ')
ax.set_xticklabels(column_labels, minor=False)
ax.set_yticklabels(row_labels, minor=False)

plt.show()

You were very close. Once you have a reference to the color bar axis, you can do what ever you want to it, including putting text labels in the middle. You might want to play with the formatting to make it more visible.

demo

CSS table-cell equal width

Here is a working fiddle with indeterminate number of cells: http://jsfiddle.net/r9yrM/1/

You can fix a width to each parent div (the table), otherwise it'll be 100% as usual.

The trick is to use table-layout: fixed; and some width on each cell to trigger it, here 2%. That will trigger the other table algorightm, the one where browsers try very hard to respect the dimensions indicated.
Please test with Chrome (and IE8- if needed). It's OK with a recent Safari but I can't remember the compatibility of this trick with them.

CSS (relevant instructions):

div {
    display: table;
    width: 250px;
    table-layout: fixed;
}

div > div {
    display: table-cell;
    width: 2%; /* or 100% according to OP comment. See edit about Safari 6 below */
}

EDIT (2013): Beware of Safari 6 on OS X, it has table-layout: fixed; wrong (or maybe just different, very different from other browsers. I didn't proof-read CSS2.1 REC table layout ;) ). Be prepared to different results.

How to shift a column in Pandas DataFrame

I suppose imports

import pandas as pd
import numpy as np

First append new row with NaN, NaN,... at the end of DataFrame (df).

s1 = df.iloc[0]    # copy 1st row to a new Series s1
s1[:] = np.NaN     # set all values to NaN
df2 = df.append(s1, ignore_index=True)  # add s1 to the end of df

It will create new DF df2. Maybe there is more elegant way but this works.

Now you can shift it:

df2.x2 = df2.x2.shift(1)  # shift what you want

How to get current class name including package name in Java?

The fully-qualified name is opbtained as follows:

String fqn = YourClass.class.getName();

But you need to read a classpath resource. So use

InputStream in = YourClass.getResourceAsStream("resource.txt");

Can I escape a double quote in a verbatim string literal?

Use a duplicated double quote.

@"this ""word"" is escaped";

outputs:

this "word" is escaped

What is the difference between i++ & ++i in a for loop?

The difference is that the post-increment operator i++ returns i as it was before incrementing, and the pre-increment operator ++i returns i as it is after incrementing. If you're asking about a typical for loop:

for (i = 0; i < 10; i++)

or

for (i = 0; i < 10; ++i)

They're exactly the same, since you're not using i++ or ++i as a part of a larger expression.

When running UPDATE ... datetime = NOW(); will all rows updated have the same date/time?

The sqlite answer is

update TABLE set mydatetime = datetime('now');

in case someone else was looking for it.

jQuery autocomplete with callback ajax json

My issue was that end users would start typing in a textbox and receive autocomplete (ACP) suggestions and update the calling control if a suggestion was selected as the ACP is designed by default. However, I also needed to update multiple other controls (textboxes, DropDowns, etc...) with data specific to the end user's selection. I have been trying to figure out an elegant solution to the issue and I feel the one I developed is worth sharing and hopefully will save you at least some time.

WebMethod (SampleWM.aspx):

  • PURPOSE:

    • To capture SQL Server Stored Procedure results and return them as a JSON String to the AJAX Caller
  • NOTES:

    • Data.GetDataTableFromSP() - Is a custom function that returns a DataTable from the results of a Stored Procedure
    • < System.Web.Services.WebMethod(EnableSession:=True) > _
    • Public Shared Function GetAutoCompleteData(ByVal QueryFilterAs String) As String

 //Call to custom function to return SP results as a DataTable
 // DataTable will consist of Field0 - Field5
 Dim params As ArrayList = New ArrayList
 params.Add("@QueryFilter|" & QueryFilter)
 Dim dt As DataTable = Data.GetDataTableFromSP("AutoComplete", params, [ConnStr])

 //Create a StringBuilder Obj to hold the JSON 
 //IE: [{"Field0":"0","Field1":"Test","Field2":"Jason","Field3":"Smith","Field4":"32","Field5":"888-555-1212"},{"Field0":"1","Field1":"Test2","Field2":"Jane","Field3":"Doe","Field4":"25","Field5":"888-555-1414"}]
 Dim jStr As StringBuilder = New StringBuilder

 //Loop the DataTable and convert row into JSON String
 If dt.Rows.Count > 0 Then
      jStr.Append("[")
      Dim RowCnt As Integer = 1
      For Each r As DataRow In dt.Rows
           jStr.Append("{")
           Dim ColCnt As Integer = 0
           For Each c As DataColumn In dt.Columns
               If ColCnt = 0 Then
                   jStr.Append("""" & c.ColumnName & """:""" & r(c.ColumnName) & """")
               Else
                   jStr.Append(",""" & c.ColumnName & """:""" & r(c.ColumnName) & """")
                End If
                ColCnt += 1
            Next

            If Not RowCnt = dt.Rows.Count Then
                jStr.Append("},")
            Else
                jStr.Append("}")
            End If

            RowCnt += 1
        Next

        jStr.Append("]")
    End If

    //Return JSON to WebMethod Caller
    Return jStr.ToString

AutoComplete jQuery (AutoComplete.aspx):

  • PURPOSE:
    • Perform the Ajax Request to the WebMethod and then handle the response

    $(function() {
      $("#LookUp").autocomplete({                
            source: function (request, response) {
                $.ajax({
                    type: "POST",
                    contentType: "application/json; charset=utf-8",
                    url: "SampleWM.aspx/GetAutoCompleteData",
                    dataType: "json",
                    data:'{QueryFilter: "' + request.term  + '"}',
                    success: function (data) {
                        response($.map($.parseJSON(data.d), function (item) {                                
                            var AC = new Object();

                            //autocomplete default values REQUIRED
                            AC.label = item.Field0;
                            AC.value = item.Field1;

                            //extend values
                            AC.FirstName = item.Field2;
                            AC.LastName = item.Field3;
                            AC.Age = item.Field4;
                            AC.Phone = item.Field5;

                            return AC
                        }));       
                    }                                             
                });
            },
            minLength: 3,
            select: function (event, ui) {                    
                $("#txtFirstName").val(ui.item.FirstName);
                $("#txtLastName").val(ui.item.LastName);
                $("#ddlAge").val(ui.item.Age);
                $("#txtPhone").val(ui.item.Phone);
             }                    
        });
     });

Break or return from Java 8 stream forEach?

I would suggest using anyMatch. Example:-

return someObjects.stream().anyMatch(obj -> 
    some_condition_met;
);

You can refer this post for understanding anyMatch:- https://beginnersbook.com/2017/11/java-8-stream-anymatch-example/

Converting an array to a function arguments list

You might want to take a look at a similar question posted on Stack Overflow. It uses the .apply() method to accomplish this.

Python element-wise tuple operations like sum

This solution doesn't require an import:

tuple(map(lambda x, y: x + y, tuple1, tuple2))

How to get JQuery.trigger('click'); to initiate a mouse click

You need to use jQuery('#bar')[0].click(); to simulate a mouse click on the actual DOM element (not the jQuery object), instead of using the .trigger() jQuery method.

Note: DOM Level 2 .click() doesn't work on some elements in Safari. You will need to use a workaround.

http://api.jquery.com/click/

Cannot read configuration file due to insufficient permissions

Go to the parent folder, right-click and select Properties. Select the Security tab, edit the permissions and Add. Click on Advanced and the Find Now. Select IIS_IUSRS and click OK and OK again. Make sure you have check Write. Click OK and OK again.

Job done!

Creating and appending text to txt file in VB.NET

This should work for you without changing program logic (by not outputting "Start error" on the top of each file) like the other answers do :) Remember to add exception handling code.

Dim filePath As String = String.Format("C:\ErrorLog_{0}.txt", DateTime.Today.ToString("dd-MMM-yyyy"))

Dim fileExists As Boolean = File.Exists(filePath)

Using writer As New StreamWriter(filePath, True)
    If Not fileExists Then
        writer.WriteLine("Start Error Log for today")
    End If
    writer.WriteLine("Error Message in  Occured at-- " & DateTime.Now)
End Using

XMLHttpRequest cannot load XXX No 'Access-Control-Allow-Origin' header

"Get" request with appending headers transform to "Options" request. So Cors policy problems occur. You have to implement "Options" request to your server.

Generate sql insert script from excel worksheet

Here is another tool that works very well...

http://www.convertcsv.com/csv-to-sql.htm

It can take tab separated values and generate an INSERT script. Just copy and paste and in the options under step 2 check the box "First row is column names"

Then scroll down and under step 3, enter your table name in the box "Schema.Table or View Name:"

Pay attention to the delete and create table check boxes as well, and make sure you examine the generated script before running it.

This is the quickest and most reliable way I've found.

JavaScript by reference vs. by value

My understanding is that this is actually very simple:

  • Javascript is always pass by value, but when a variable refers to an object (including arrays), the "value" is a reference to the object.
  • Changing the value of a variable never changes the underlying primitive or object, it just points the variable to a new primitive or object.
  • However, changing a property of an object referenced by a variable does change the underlying object.

So, to work through some of your examples:

function f(a,b,c) {
    // Argument a is re-assigned to a new value.
    // The object or primitive referenced by the original a is unchanged.
    a = 3;
    // Calling b.push changes its properties - it adds
    // a new property b[b.length] with the value "foo".
    // So the object referenced by b has been changed.
    b.push("foo");
    // The "first" property of argument c has been changed.
    // So the object referenced by c has been changed (unless c is a primitive)
    c.first = false;
}

var x = 4;
var y = ["eeny", "miny", "mo"];
var z = {first: true};
f(x,y,z);
console.log(x, y, z.first); // 4, ["eeny", "miny", "mo", "foo"], false

Example 2:

var a = ["1", "2", {foo:"bar"}];
var b = a[1]; // b is now "2";
var c = a[2]; // c now references {foo:"bar"}
a[1] = "4";   // a is now ["1", "4", {foo:"bar"}]; b still has the value
              // it had at the time of assignment
a[2] = "5";   // a is now ["1", "4", "5"]; c still has the value
              // it had at the time of assignment, i.e. a reference to
              // the object {foo:"bar"}
console.log(b, c.foo); // "2" "bar"

CakePHP find method with JOIN

        $services = $this->Service->find('all', array(
            'limit' =>4,
            'fields' => array('Service.*','ServiceImage.*'),
            'joins' => array(
                array(
                        'table' => 'services_images',
                        'alias' => 'ServiceImage',
                        'type' => 'INNER',
                        'conditions' => array(
                        'ServiceImage.service_id' =>'Service.id'
                        )
                    ),
                ),
            )
        );

It goges to array is null.

SQL statement to get column type

In my case I needed to get the data type for Dynamic SQL (Shudder!) anyway here is a function that I created that returns the full data type. For example instead of returning 'decimal' it would return DECIMAL(18,4): dbo.GetLiteralDataType

Android getText from EditText field

You can simply get the text in editText by applying below code:

EditText editText=(EditText)findViewById(R.id.vnosZadeve);
String text=editText.getText().toString();

then you can toast string text!

Happy coding!

Python Script to convert Image into Byte array

This works for me

# Convert image to bytes
import PIL.Image as Image
pil_im = Image.fromarray(image)
b = io.BytesIO()
pil_im.save(b, 'jpeg')
im_bytes = b.getvalue()
return im_bytes

Tomcat: LifecycleException when deploying

I got stuck and problem solved Don't use the path that is "Map Network Drive", but use the \server\folder structure instead

Java - How to find the redirected url of a url?

Have a look at the HttpURLConnection class API documentation, especially setInstanceFollowRedirects().

Check if Internet Connection Exists with jQuery?

You can try by sending XHR Requests a few times, and then if you get errors it means there's a problem with the internet connection.

Edit: I found this JQuery script which is doing what you are asking for, I didn't test it though.

Update MySQL using HTML Form and PHP

Update query may have some issues

$query = "UPDATE anstalld SET mandag = '$mandag', tisdag = '$tisdag', onsdag = '$onsdag', torsdag = '$torsdag', fredag = '$fredag' WHERE namn = '$namn' ";
echo $query;

Please make sure that, your variable not having values with qoutes ( ' ), May be the query is breaking somewhere.

echo the query and try to execute in phpmyadmin itself. Then you can find the issues.

Check if the file exists using VBA

Use the Office FileDialog object to have the user pick a file from the filesystem. Add a reference in your VB project or in the VBA editor to Microsoft Office Library and look in the help. This is much better than having people enter full paths.

Here is an example using msoFileDialogFilePicker to allow the user to choose multiple files. You could also use msoFileDialogOpen.

'Note: this is Excel VBA code
Public Sub LogReader()
    Dim Pos As Long
    Dim Dialog As Office.FileDialog
    Set Dialog = Application.FileDialog(msoFileDialogFilePicker)

    With Dialog
        .AllowMultiSelect = True
        .ButtonName = "C&onvert"
        .Filters.Clear
        .Filters.Add "Log Files", "*.log", 1
        .Title = "Convert Logs to Excel Files"
        .InitialFileName = "C:\InitialPath\"
        .InitialView = msoFileDialogViewList

        If .Show Then
            For Pos = 1 To .SelectedItems.Count
                LogRead .SelectedItems.Item(Pos) ' process each file
            Next
        End If
    End With
End Sub

There are lots of options, so you'll need to see the full help files to understand all that is possible. You could start with Office 2007 FileDialog object (of course, you'll need to find the correct help for the version you're using).

Windows service on Local Computer started and then stopped error

I have found it very handy to convert your existing windows service to a console by simply changing your program with the following. With this change you can run the program by debugging in visual studio or running the executable normally. But it will also work as a windows service. I also made a blog post about it

program.cs

class Program
{
    static void Main()
    {
        var program = new YOUR_PROGRAM();
        if (Environment.UserInteractive)
        {
            program.Start();
        }
        else
        {
            ServiceBase.Run(new ServiceBase[]
            {
                program
            });
        }
    }
}

YOUR_PROGRAM.cs

[RunInstallerAttribute(true)]
public class YOUR_PROGRAM : ServiceBase
{
    public YOUR_PROGRAM()
    {
        InitializeComponent();
    }

    protected override void OnStart(string[] args)
    {
        Start();
    }

    protected override void OnStop()
    {
        //Stop Logic Here
    }

    public void Start()
    {
        //Start Logic here
    }
}

TypeError: 'list' object cannot be interpreted as an integer

For me i was getting this error because i needed to put the arrays in paratheses. The error is a bit tricky in this case...

ie. concatenate((a, b)) is right

not concatenate(a, b)

hope that helps.

calling a function from class in python - different way

You need to have an instance of a class to use its methods. Or if you don't need to access any of classes' variables (not static parameters) then you can define the method as static and it can be used even if the class isn't instantiated. Just add @staticmethod decorator to your methods.

class MathsOperations:
    @staticmethod
    def testAddition (x, y):
        return x + y
    @staticmethod
    def testMultiplication (a, b):
        return a * b

docs: http://docs.python.org/library/functions.html#staticmethod

Is there an upside down caret character?

There's always a lowercase "v". But seriously, aside from Unicode, all I can find would be &darr, which looks like ↓.

Redirecting to a page after submitting form in HTML

What you could do is, a validation of the values, for example:

if the value of the input of fullanme is greater than some value length and if the value of the input of address is greater than some value length then redirect to a new page, otherwise shows an error for the input.

_x000D_
_x000D_
// We access to the inputs by their id's
let fullname = document.getElementById("fullname");
let address = document.getElementById("address");

// Error messages
let errorElement = document.getElementById("name_error");
let errorElementAddress = document.getElementById("address_error");

// Form
let contactForm = document.getElementById("form");

// Event listener
contactForm.addEventListener("submit", function (e) {
  let messageName = [];
  let messageAddress = [];
  
    if (fullname.value === "" || fullname.value === null) {
    messageName.push("* This field is required");
  }

  if (address.value === "" || address.value === null) {
    messageAddress.push("* This field is required");
  }

  // Statement to shows the errors
  if (messageName.length || messageAddress.length > 0) {
    e.preventDefault();
    errorElement.innerText = messageName;
    errorElementAddress.innerText = messageAddress;
  }
  
   // if the values length is filled and it's greater than 2 then redirect to this page
    if (
    (fullname.value.length > 2,
    address.value.length > 2)
  ) {
    e.preventDefault();
    window.location.assign("https://www.google.com");
  }

});
_x000D_
.error {
  color: #000;
}

.input-container {
  display: flex;
  flex-direction: column;
  margin: 1rem auto;
}
_x000D_
<html>
  <body>
    <form id="form" method="POST">
    <div class="input-container">
    <label>Full name:</label>
      <input type="text" id="fullname" name="fullname">
      <div class="error" id="name_error"></div>
      </div>
      
      <div class="input-container">
      <label>Address:</label>
      <input type="text" id="address" name="address">
      <div class="error" id="address_error"></div>
      </div>
      <button type="submit" id="submit_button" value="Submit request" >Submit</button>
    </form>
  </body>
</html>
_x000D_
_x000D_
_x000D_

Can't clone a github repo on Linux via HTTPS

As JERC said, make sure you have an updated version of git. If you are only using the default settings, when you try to install git you will get version 1.7.1. Other than manually downloading and installing the latest version of get, you can also accomplish this by adding a new repository to yum.

From tecadmin.net:

Download and install the rpmforge repository:

# use this for 64-bit
rpm -i 'http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm'
# use this for 32-bit
rpm -i 'http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.i686.rpm'

# then run this in either case
rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt

Then you need to enable the rpmforge-extras. Edit /etc/yum.repos.d/rpmforge.repo and change enabled = 0 to enabled = 1 under [rpmforge-extras]. The file looks like this:

### Name: RPMforge RPM Repository for RHEL 6 - dag
### URL: http://rpmforge.net/
[rpmforge]
name = RHEL $releasever - RPMforge.net - dag
baseurl = http://apt.sw.be/redhat/el6/en/$basearch/rpmforge
mirrorlist = http://mirrorlist.repoforge.org/el6/mirrors-rpmforge
#mirrorlist = file:///etc/yum.repos.d/mirrors-rpmforge
enabled = 1
protect = 0
gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-rpmforge-dag
gpgcheck = 1

[rpmforge-extras]
name = RHEL $releasever - RPMforge.net - extras
baseurl = http://apt.sw.be/redhat/el6/en/$basearch/extras
mirrorlist = http://mirrorlist.repoforge.org/el6/mirrors-rpmforge-extras
#mirrorlist = file:///etc/yum.repos.d/mirrors-rpmforge-extras
enabled = 0 ####### CHANGE THIS LINE TO "enabled = 1" #############
protect = 0
gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-rpmforge-dag
gpgcheck = 1

[rpmforge-testing]
name = RHEL $releasever - RPMforge.net - testing
baseurl = http://apt.sw.be/redhat/el6/en/$basearch/testing
mirrorlist = http://mirrorlist.repoforge.org/el6/mirrors-rpmforge-testing
#mirrorlist = file:///etc/yum.repos.d/mirrors-rpmforge-testing
enabled = 0
protect = 0
gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-rpmforge-dag
gpgcheck = 1

Once you've done this, then you can update git with

yum update git

I'm not sure why, but they then suggest disabling rpmforge-extras (change back to enabled = 0) and then running yum clean all.

Most likely you'll need to use sudo for these commands.

c++ string array initialization

In C++11 you can. A note beforehand: Don't new the array, there's no need for that.

First, string[] strArray is a syntax error, that should either be string* strArray or string strArray[]. And I assume that it's just for the sake of the example that you don't pass any size parameter.

#include <string>

void foo(std::string* strArray, unsigned size){
  // do stuff...
}

template<class T>
using alias = T;

int main(){
  foo(alias<std::string[]>{"hi", "there"}, 2);
}

Note that it would be better if you didn't need to pass the array size as an extra parameter, and thankfully there is a way: Templates!

template<unsigned N>
void foo(int const (&arr)[N]){
  // ...
}

Note that this will only match stack arrays, like int x[5] = .... Or temporary ones, created by the use of alias above.

int main(){
  foo(alias<int[]>{1, 2, 3});
}

Serialize an object to string

My 2p...

        string Serialise<T>(T serialisableObject)
        {
            var xmlSerializer = new XmlSerializer(serialisableObject.GetType());

            using (var ms = new MemoryStream())
            {
                using (var xw = XmlWriter.Create(ms, 
                    new XmlWriterSettings()
                        {
                            Encoding = new UTF8Encoding(false),
                            Indent = true,
                            NewLineOnAttributes = true,
                        }))
                {
                    xmlSerializer.Serialize(xw,serialisableObject);
                    return Encoding.UTF8.GetString(ms.ToArray());
                }
            }
        }

Filter Pyspark dataframe column with None value

To obtain entries whose values in the dt_mvmt column are not null we have

df.filter("dt_mvmt is not NULL")

and for entries which are null we have

df.filter("dt_mvmt is NULL")

Error LNK2019 unresolved external symbol _main referenced in function "int __cdecl invoke_main(void)" (?invoke_main@@YAHXZ)

I got the same error because I created a new object from a templated class using the template name without specifying the type explicitly like this:

int main()
{

    MyClass<T> Test2(5.60, 6.6); <- This is wrong
           ^^^
    return 0;
}

The correct way to do it was to specify exactly what T was like this:

int main()
{

    MyClass<double> Test2(5.60, 6.6); <- This is right
            ^^^^^^
    return 0;
}

How to get named excel sheets while exporting from SSRS

The Rectangle method

The simplest and most reliable way I've found of achieving worksheets/page-breaks is with use of the rectangle tool.

Group your page within rectangles or a single rectangle that fills the page in a sub-report, as follows:

  • The quickest way I've found of placing the rectangle is to draw it around the objects you wish to place in the rectangle.

  • Right click and in the layout menu, send the rectangle to back.

  • Select all your objects and drag them slightly, but be sure they land in the same place they were. They will all now be in the rectangle.

In the rectangle properties you can set the page-break to occur at the start or end of the rectangle and name of the page can be based on an expression.

The worksheets will be named the same as the name of the page.

Duplicate names will have a number in brackets suffix.

Note: Ensure that the names are valid worksheet names.

Laravel-5 how to populate select box from database with id value and name value

For Laravel 5 :

$items = Items::lists('name', 'id');

Push an item onto the beginning of the collection.

$items->prepend($value, $key = null);

Printing a java map Map<String, Object> - How?

You may use Map.entrySet() method:

for (Map.Entry entry : objectSet.entrySet())
{
    System.out.println("key: " + entry.getKey() + "; value: " + entry.getValue());
}

iPhone - Get Position of UIView within entire UIWindow

Swift 5+:

let globalPoint = aView.superview?.convert(aView.frame.origin, to: nil)

Uninstall all installed gems, in OSX?

The only command helped me to cleanup all gems and ignores default gems, which can't be uninstalled

for x in `gem list --no-versions`; do gem uninstall $x -a -x -I; done

Convert a PHP script into a stand-alone windows executable

Peachpie

http://www.peachpie.io

https://github.com/iolevel/peachpie

Peachpie is PHP 7 compiler based on Roslyn by Microsoft and drawing from popular Phalanger. It allows PHP to be executed within the .NET/.NETCore by compiling the PHP code to pure MSIL.

Phalanger

http://v4.php-compiler.net/

http://wiki.php-compiler.net/Phalanger_Wiki

https://github.com/devsense/phalanger

Phalanger is a project which was started at Charles University in Prague and was supported by Microsoft. It compiles source code written in the PHP scripting language into CIL (Common Intermediate Language) byte-code. It handles the beginning of a compiling process which is completed by the JIT compiler component of the .NET Framework. It does not address native code generation nor optimization. Its purpose is to compile PHP scripts into .NET assemblies, logical units containing CIL code and meta-data.

Bambalam

https://github.com/xZero707/Bamcompile/

Bambalam PHP EXE Compiler/Embedder is a free command line tool to convert PHP applications to standalone Windows .exe applications. The exe files produced are totally standalone, no need for php dlls etc. The php code is encoded using the Turck MMCache Encode library so it's a perfect solution if you want to distribute your application while protecting your source code. The converter is also suitable for producing .exe files for windowed PHP applications (created using for example the WinBinder library). It's also good for making stand-alone PHP Socket servers/clients (using the php_sockets.dll extension). It's NOT really a compiler in the sense that it doesn't produce native machine code from PHP sources, but it works!

ZZEE PHPExe

http://www.zzee.com/phpexe/

ZZEE PHPExe compiles PHP, HTML, Javascript, Flash and other web files into Windows GUI exes. You can rapidly develop Windows GUI applications by employing the familiar PHP web paradigm. You can use the same code for online and Windows applications with little or no modification. It is a Commercial product.

phc-win

http://wiki.swiftlytilting.com/Phc-win

The PHP extension bcompiler is used to compile PHP script code into PHP bytecode. This bytecode can be included just like any php file as long as the bcompiler extension is loaded. Once all the bytecode files have been created, a modified Embeder is used to pack all of the project files into the program exe.

Requires

  • php5ts.dll
  • php_win32std.dll
  • php_bcompiler.dll
  • php-embed.ini

ExeOutput

http://www.exeoutput.com/

Commercial

WinBinder

http://winbinder.org/

WinBinder is an open source extension to PHP, the script programming language. It allows PHP programmers to easily build native Windows applications, producing quick and rewarding results with minimum effort. Even short scripts with a few dozen lines can generate a useful program, thanks to the power and flexibility of PHP.

PHPDesktop

https://github.com/cztomczak/phpdesktop

PHP Desktop is an open source project founded by Czarek Tomczak in 2012 to provide a way for developing native desktop applications using web technologies such as PHP, HTML5, JavaScript & SQLite. This project is more than just a PHP to EXE compiler, it embeds a web-browser (Internet Explorer or Chrome embedded), a Mongoose web-server and a PHP interpreter. The development workflow you are used to remains the same, the step of turning an existing website into a desktop application is basically a matter of copying it to "www/" directory. Using SQLite database is optional, you could embed mysql/postgresql database in application's installer.

PHP Nightrain

https://github.com/kjellberg/nightrain

Using PHP Nightrain you will be able to deploy and run HTML, CSS, JavaScript and PHP web applications as a native desktop application on Windows, Mac and the Linux operating systems. Popular PHP Frameworks (e.g. CakePHP, Laravel, Drupal, etc…) are well supported!

phc-win "fork"

https://github.com/RDashINC/phc-win

A more-or-less forked version of phc-win, it uses the same techniques as phc-win but supports almost all modern PHP versions. (5.3, 5.4, 5.5, 5.6, etc) It also can use Enigma VB to combine the php5ts.dll with your exe, aswell as UPX compress it. Lastly, it has win32std and winbinder compilied statically into PHP.

EDIT

Another option is to use

http://www.appcelerator.com/products/titanium-cross-platform-application-development/

an online compiler that can build executables for a number of different platforms, from a number of different languages including PHP

TideSDK

http://www.tidesdk.org/

TideSDK is actually the renamed Titanium Desktop project. Titanium remained focused on mobile, and abandoned the desktop version, which was taken over by some people who have open sourced it and dubbed it TideSDK.

Generally, TideSDK uses HTML, CSS and JS to render applications, but it supports scripted languages like PHP, as a plug-in module, as well as other scripting languages like Python and Ruby.

Read CSV file column by column

Finds all files in folder and write that data to ArrayList row.

Initialize

ArrayList<ArrayList<String>> row=new ArrayList<ArrayList<String>>();
BufferedReader br=null;

For Accessing row

for(ArrayList<String> data:row){
data.get(col no); 
}
or row.get(0).get(0) // getting first row first col

Functions that reads all files from folders and concatenate them row.

static void readData(){
String path="C:\\Users\\Galaxy Computers\\Desktop\\Java project\\Nasdaq\\";
File files=new File(path);
String[] list=files.list();

try {
        String sCurrentLine;
       char check;
       for(String filename:list){ 
        br = new BufferedReader(new FileReader(path+filename));
        br.readLine();//If file contains uneccessary first line.
        while ((sCurrentLine = br.readLine()) != null) {

           row.add(splitLine(sCurrentLine));
        }
        }
        }

    } catch (IOException e) {
        e.printStackTrace();
    } 
        try {
            if (br != null)br.close();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }


   static ArrayList<String> splitLine(String line){
   String[] ar=line.split(",");
   ArrayList<String> d=new ArrayList<String>();
   for(String data:ar){
    d.add(data);
   }

   return d; 
   } 

Get clicked item and its position in RecyclerView

Use below code:-

public class SergejAdapter extends RecyclerView.Adapter<SergejAdapter.MyViewHolder>{

...

class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{


    @Override
    public void onClick(View v) {
        // here you use position
        int position = getAdapterPosition();
        ...

    }
}
}

What's the "Content-Length" field in HTTP header?

From this page

The most common use of POST, by far, is to submit HTML form data to CGI scripts. In this case, the Content-Type: header is usually application/x-www-form-urlencoded, and the Content-Length: header gives the length of the URL-encoded form data (here's a note on URL-encoding). The CGI script receives the message body through STDIN, and decodes it. Here's a typical form submission, using POST:

POST /path/script.cgi HTTP/1.0
From: [email protected]
User-Agent: HTTPTool/1.0
Content-Type: application/x-www-form-urlencoded
Content-Length: 32

Can I pass variable to select statement as column name in SQL Server

You can't use variable names to bind columns or other system objects, you need dynamic sql

DECLARE @value varchar(10)  
SET @value = 'intStep'  
DECLARE @sqlText nvarchar(1000); 

SET @sqlText = N'SELECT ' + @value + ' FROM dbo.tblBatchDetail'
Exec (@sqlText)

Change windows hostname from command line

I don't know of a command to do this, but you could do it in VBScript or something similar. Somthing like:

sNewName = "put new name here" 

Set oShell = CreateObject ("WSCript.shell" ) 

sCCS = "HKLM\SYSTEM\CurrentControlSet\" 
sTcpipParamsRegPath = sCCS & "Services\Tcpip\Parameters\" 
sCompNameRegPath = sCCS & "Control\ComputerName\" 

With oShell 
.RegDelete sTcpipParamsRegPath & "Hostname" 
.RegDelete sTcpipParamsRegPath & "NV Hostname" 

.RegWrite sCompNameRegPath & "ComputerName\ComputerName", sNewName 
.RegWrite sCompNameRegPath & "ActiveComputerName\ComputerName", sNewName 
.RegWrite sTcpipParamsRegPath & "Hostname", sNewName 
.RegWrite sTcpipParamsRegPath & "NV Hostname", sNewName 
End With ' oShell 

MsgBox "Computer name changed, please reboot your computer" 

Original

How to remove carriage return and newline from a variable in shell script

yet another solution uses tr:

echo $testVar | tr -d '\r'
cat myscript | tr -d '\r'

the option -d stands for delete.

How to make an autocomplete address field with google maps api?

Drifting a bit, but it would be relatively easy to autofill the US City/State or CA City/Provence when the user enters her postal code using a lookup table.

Here's how you could do it if you could force people to bend to your will:

  1. User enters: postal (zip) code

    You fill: state, city (province, for Canada)

  2. User starts to enter: streetname

    You: autofill

  3. You display: a range of allowed address numbers

    User: enters the number

Done.

Here's how it is natural for people to do it:

  1. User enters: address number

    You: do nothing

  2. User starts to enter: street name

    You: autofill, drawing from a massive list of every street in the country

  3. User enters: city

    You: autofill

  4. User enters: state/provence

    You: is it worth autofilling a few chars?

  5. You: autofill postal (zip) code, if you can (because some codes straddle cities).


Now you know why people charge $$$ to do this. :)

For the street address, consider there are two parts: numeric and streetname. If you have the zip code, then you can narrow down the available streets, but most people enter the numeric part first, which is backwa

What characters are allowed in an email address?

A good read on the matter.

Excerpt:

These are all valid email addresses!

"Abc\@def"@example.com
"Fred Bloggs"@example.com
"Joe\\Blow"@example.com
"Abc@def"@example.com
customer/[email protected]
\[email protected]
!def!xyz%[email protected]
[email protected]

AngularJS access scope from outside js function

You can also try:

function change() {
    var scope = angular.element( document.getElementById('outer') ).scope();
    scope.$apply(function(){
        scope.msg = 'Superhero';
    })
}

An "and" operator for an "if" statement in Bash

Try this:

if [ $STATUS -ne 200 -a "$STRING" != "$VALUE" ]; then

How to change the timeout on a .NET WebClient object

As Sohnee says, using System.Net.HttpWebRequest and set the Timeout property instead of using System.Net.WebClient.

You can't however set an infinite timeout value (it's not supported and attempting to do so will throw an ArgumentOutOfRangeException).

I'd recommend first performing a HEAD HTTP request and examining the Content-Length header value returned to determine the number of bytes in the file you're downloading and then setting the timeout value accordingly for subsequent GET request or simply specifying a very long timeout value that you would never expect to exceed.

What is the meaning of CTOR?

Usually this region should contains the constructors of the class

How to unnest a nested list

Use reduce function

reduce(lambda x, y: x + y, A, [])

Or sum

sum(A, [])

AngularJS ui-router login authentication

I Created this module to help make this process piece of cake

You can do things like:

$routeProvider
  .state('secret',
    {
      ...
      permissions: {
        only: ['admin', 'god']
      }
    });

Or also

$routeProvider
  .state('userpanel',
    {
      ...
      permissions: {
        except: ['not-logged-in']
      }
    });

It's brand new but worth checking out!

https://github.com/Narzerus/angular-permission

Spring: return @ResponseBody "ResponseEntity<List<JSONObject>>"

Now I return Object. I don't know better solution, but it works.

@RequestMapping(value="", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody ResponseEntity<Object> getAll() {
    List<Entity> entityList = entityManager.findAll();

    List<JSONObject> entities = new ArrayList<JSONObject>();
    for (Entity n : entityList) {
        JSONObject Entity = new JSONObject();
        entity.put("id", n.getId());
        entity.put("address", n.getAddress());
        entities.add(entity);
    }
    return new ResponseEntity<Object>(entities, HttpStatus.OK);
}

Explanation of JSONB introduced by PostgreSQL

A simple explanation of the difference between json and jsonb (original image by PostgresProfessional):

SELECT '{"c":0,   "a":2,"a":1}'::json, '{"c":0,   "a":2,"a":1}'::jsonb;

          json          |        jsonb 
------------------------+--------------------- 
 {"c":0,   "a":2,"a":1} | {"a": 1, "c": 0} 
(1 row)
  • json: textual storage «as is»
  • jsonb: no whitespaces
  • jsonb: no duplicate keys, last key win
  • jsonb: keys are sorted

More in speech video and slide show presentation by jsonb developers. Also they introduced JsQuery, pg.extension provides powerful jsonb query language

What is the javascript filename naming convention?

I'm not aware of any particular convention for javascript files as they aren't really unique on the web versus css files or html files or any other type of file like that. There are some "safe" things you can do that make it less likely you will accidentally run into a cross platform issue:

  1. Use all lowercase filenames. There are some operating systems that are not case sensitive for filenames and using all lowercase prevents inadvertently using two files that differ only in case that might not work on some operating systems.
  2. Don't use spaces in the filename. While this technically can be made to work there are lots of reasons why spaces in filenames can lead to problems.
  3. A hyphen is OK for a word separator. If you want to use some sort of separator for multiple words instead of a space or camelcase as in various-scripts.js, a hyphen is a safe and useful and commonly used separator.
  4. Think about using version numbers in your filenames. When you want to upgrade your scripts, plan for the effects of browser or CDN caching. The simplest way to use long term caching (for speed and efficiency), but immediate and safe upgrades when you upgrade a JS file is to include a version number in the deployed filename or path (like jQuery does with jquery-1.6.2.js) and then you bump/change that version number whenever you upgrade/change the file. This will guarantee that no page that requests the newer version is ever served the older version from a cache.

Merge PDF files

from PyPDF2 import PdfFileMerger
import webbrowser
import os
dir_path = os.path.dirname(os.path.realpath(__file__))

def list_files(directory, extension):
    return (f for f in os.listdir(directory) if f.endswith('.' + extension))

pdfs = list_files(dir_path, "pdf")

merger = PdfFileMerger()

for pdf in pdfs:
    merger.append(open(pdf, 'rb'))

with open('result.pdf', 'wb') as fout:
    merger.write(fout)

webbrowser.open_new('file://'+ dir_path + '/result.pdf')

Git Repo: https://github.com/mahaguru24/Python_Merge_PDF.git

Write HTML string in JSON

You should escape the characters like double quotes in the html string by adding "\"

eg: <h2 class=\"fg-white\">

What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?

When a assembly' s AssemblyVersion is changed, If it has strong name, the referencing assemblies need to be recompiled, otherwise the assembly does not load! If it does not have strong name, if not explicitly added to project file, it will not be copied to output directory when build so you may miss depending assemblies, especially after cleaning the output directory.