Programs & Examples On #Scoping

What is lexical scope?

Scope defines the area, where functions, variables and such are available. The availability of a variable for example is defined within its the context, let's say the function, file, or object, they are defined in. We usually call these local variables.

The lexical part means that you can derive the scope from reading the source code.

Lexical scope is also known as static scope.

Dynamic scope defines global variables that can be called or referenced from anywhere after being defined. Sometimes they are called global variables, even though global variables in most programmin languages are of lexical scope. This means, it can be derived from reading the code that the variable is available in this context. Maybe one has to follow a uses or includes clause to find the instatiation or definition, but the code/compiler knows about the variable in this place.

In dynamic scoping, by contrast, you search in the local function first, then you search in the function that called the local function, then you search in the function that called that function, and so on, up the call stack. "Dynamic" refers to change, in that the call stack can be different every time a given function is called, and so the function might hit different variables depending on where it is called from. (see here)

To see an interesting example for dynamic scope see here.

For further details see here and here.

Some examples in Delphi/Object Pascal

Delphi has lexical scope.

unit Main;
uses aUnit;  // makes available all variables in interface section of aUnit

interface

  var aGlobal: string; // global in the scope of all units that use Main;
  type 
    TmyClass = class
      strict private aPrivateVar: Integer; // only known by objects of this class type
                                    // lexical: within class definition, 
                                    // reserved word private   
      public aPublicVar: double;    // known to everyboday that has access to a 
                                    // object of this class type
    end;

implementation

  var aLocalGlobal: string; // known to all functions following 
                            // the definition in this unit    

end.

The closest Delphi gets to dynamic scope is the RegisterClass()/GetClass() function pair. For its use see here.

Let's say that the time RegisterClass([TmyClass]) is called to register a certain class cannot be predicted by reading the code (it gets called in a button click method called by the user), code calling GetClass('TmyClass') will get a result or not. The call to RegisterClass() does not have to be in the lexical scope of the unit using GetClass();

Another possibility for dynamic scope are anonymous methods (closures) in Delphi 2009, as they know the variables of their calling function. It does not follow the calling path from there recursively and therefore is not fully dynamic.

Asynchronously wait for Task<T> to complete with timeout

A few variants of Andrew Arnott's answer:

  1. If you want to wait for an existing task and find out whether it completed or timed out, but don't want to cancel it if the timeout occurs:

    public static async Task<bool> TimedOutAsync(this Task task, int timeoutMilliseconds)
    {
        if (timeoutMilliseconds < 0 || (timeoutMilliseconds > 0 && timeoutMilliseconds < 100)) { throw new ArgumentOutOfRangeException(); }
    
        if (timeoutMilliseconds == 0) {
            return !task.IsCompleted; // timed out if not completed
        }
        var cts = new CancellationTokenSource();
        if (await Task.WhenAny( task, Task.Delay(timeoutMilliseconds, cts.Token)) == task) {
            cts.Cancel(); // task completed, get rid of timer
            await task; // test for exceptions or task cancellation
            return false; // did not timeout
        } else {
            return true; // did timeout
        }
    }
    
  2. If you want to start a work task and cancel the work if the timeout occurs:

    public static async Task<T> CancelAfterAsync<T>( this Func<CancellationToken,Task<T>> actionAsync, int timeoutMilliseconds)
    {
        if (timeoutMilliseconds < 0 || (timeoutMilliseconds > 0 && timeoutMilliseconds < 100)) { throw new ArgumentOutOfRangeException(); }
    
        var taskCts = new CancellationTokenSource();
        var timerCts = new CancellationTokenSource();
        Task<T> task = actionAsync(taskCts.Token);
        if (await Task.WhenAny(task, Task.Delay(timeoutMilliseconds, timerCts.Token)) == task) {
            timerCts.Cancel(); // task completed, get rid of timer
        } else {
            taskCts.Cancel(); // timer completed, get rid of task
        }
        return await task; // test for exceptions or task cancellation
    }
    
  3. If you have a task already created that you want to cancel if a timeout occurs:

    public static async Task<T> CancelAfterAsync<T>(this Task<T> task, int timeoutMilliseconds, CancellationTokenSource taskCts)
    {
        if (timeoutMilliseconds < 0 || (timeoutMilliseconds > 0 && timeoutMilliseconds < 100)) { throw new ArgumentOutOfRangeException(); }
    
        var timerCts = new CancellationTokenSource();
        if (await Task.WhenAny(task, Task.Delay(timeoutMilliseconds, timerCts.Token)) == task) {
            timerCts.Cancel(); // task completed, get rid of timer
        } else {
            taskCts.Cancel(); // timer completed, get rid of task
        }
        return await task; // test for exceptions or task cancellation
    }
    

Another comment, these versions will cancel the timer if the timeout does not occur, so multiple calls will not cause timers to pile up.

sjb

How to extract duration time from ffmpeg output?

In case of one request parameter it is simplier to use mediainfo and its output formatting like this (for duration; answer in milliseconds)

mediainfo --Output="General;%Duration%" ~/work/files/testfiles/+h263_aac.avi 

outputs

24840

"Gradle Version 2.10 is required." Error

Download the latest gradle-3.0-all.zip from

http://gradle.org/gradle-download/

download from Complete Distribution link

open in android studio file ->settings ->gradle

open the path and paste the downloaded zip folder gradle-3.0 in that folder

change your gradle 2.8 to gradle 3.0 in file ->settings ->gradle

Or you can change your gradle wrapper in the project

edit YourProject\gradle\wrapper\gradle-wrapper.properties file and edit the field distributionUrl in to

distributionUrl= https://services.gradle.org/distributions/gradle-3.0-all.zip

Get the last non-empty cell in a column in Google Sheets

This seems like the simplest solution that I've found to retrieve the last value in an ever-expanding column:

=INDEX(A:A,COUNTA(A:A),1)

Merge two objects with ES6

Another aproach is:

let result = { ...item, location : { ...response } }

But Object spread isn't yet standardized.

May also be helpful: https://stackoverflow.com/a/32926019/5341953

Font Awesome 5 font-family issue

I found a solution.

  • Integrate fontawesome-all.css
  • At the end of file Search the second @font-face and replace

    font-family: 'Font Awesome 5 Free';

With

font-family: 'Font Awesome 5 FreeR';

And replace:

.far {
  font-family: 'Font Awesome 5 Free';
  font-weight: 400; }

With

.far {
  font-family: 'Font Awesome 5 FreeR';
  font-weight: 400; }

How to get Text BOLD in Alert or Confirm box?

The alert() dialog is not rendered in HTML, and thus the HTML you have embedded is meaningless.

You'd need to use a custom modal to achieve that.

How do I center align horizontal <UL> menu?

.topmenu-design
{
    display: inline-table;
}

That all!

Check image width and height before upload with Javascript

function uploadfile(ctrl) {
    var validate = validateimg(ctrl);

    if (validate) {
        if (window.FormData !== undefined) {
            ShowLoading();
            var fileUpload = $(ctrl).get(0);
            var files = fileUpload.files;


            var fileData = new FormData();


            for (var i = 0; i < files.length; i++) {
                fileData.append(files[i].name, files[i]);
            }


            fileData.append('username', 'Wishes');

            $.ajax({
                url: 'UploadWishesFiles',
                type: "POST",
                contentType: false,
                processData: false,
                data: fileData,
                success: function(result) {
                    var id = $(ctrl).attr('id');
                    $('#' + id.replace('txt', 'hdn')).val(result);

                    $('#imgPictureEn').attr('src', '../Data/Wishes/' + result).show();

                    HideLoading();
                },
                error: function(err) {
                    alert(err.statusText);
                    HideLoading();
                }
            });
        } else {
            alert("FormData is not supported.");
        }

    }

Difference between binary semaphore and mutex

I think most of the answers here were confusing especially those saying that mutex can be released only by the process that holds it but semaphore can be signaled by ay process. The above line is kind of vague in terms of semaphore. To understand we should know that there are two kinds of semaphore one is called counting semaphore and the other is called a binary semaphore. In counting semaphore handles access to n number of resources where n can be defined before the use. Each semaphore has a count variable, which keeps the count of the number of resources in use, initially, it is set to n. Each process that wishes to uses a resource performs a wait() operation on the semaphore (thereby decrementing the count). When a process releases a resource, it performs a release() operation (incrementing the count). When the count becomes 0, all the resources are being used. After that, the process waits until the count becomes more than 0. Now here is the catch only the process that holds the resource can increase the count no other process can increase the count only the processes holding a resource can increase the count and the process waiting for the semaphore again checks and when it sees the resource available it decreases the count again. So in terms of binary semaphore, only the process holding the semaphore can increase the count, and count remains zero until it stops using the semaphore and increases the count and other process gets the chance to access the semaphore.

The main difference between binary semaphore and mutex is that semaphore is a signaling mechanism and mutex is a locking mechanism, but binary semaphore seems to function like mutex that creates confusion, but both are different concepts suitable for a different kinds of work.

Disable nginx cache for JavaScript files

Remember set sendfile off; or cache headers doesn't work. I use this snipped:

location / {

        index index.php index.html index.htm;
        try_files $uri $uri/ =404; #.s. el /index.html para html5Mode de angular

        #.s. kill cache. use in dev
        sendfile off;
        add_header Last-Modified $date_gmt;
        add_header Cache-Control 'no-store, no-cache, must-revalidate, proxy-revalidate, max-age=0';
        if_modified_since off;
        expires off;
        etag off;
        proxy_no_cache 1;
        proxy_cache_bypass 1; 
    }

How do I get the current mouse screen coordinates in WPF?

Mouse.GetPosition(mWindow) gives you the mouse position relative to the parameter of your choice. mWindow.PointToScreen() convert the position to a point relative to the screen.

So mWindow.PointToScreen(Mouse.GetPosition(mWindow)) gives you the mouse position relative to the screen, assuming that mWindow is a window(actually, any class derived from System.Windows.Media.Visual will have this function), if you are using this inside a WPF window class, this should work.

Difference between array_push() and $array[] =

explain: 1.the first one declare the variable in array.

2.the second array_push method is used to push the string in the array variable.

3.finally it will print the result.

4.the second method is directly store the string in the array.

5.the data is printed in the array values in using print_r method.

this two are same

TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received type undefined raised when starting react app

We ejected from react-scripts and so could not simply upgrade the package.json entry to fix this.

Instead, we did this: 1.) in a new directory, create a new project -> $> npx create-react-app foo-project 2.) and then eject it -> cd ./foo-project && npm run eject 3.) now copy the files from /foo-project/config into the config directory of our main app and fire up your dev server

hope this helps others in a similar bind.

hide/show a image in jquery

With image class name:

$('.img_class').hide(); // to hide image
$('.img_class').show(); // to show image

With image Id :

$('#img_id').hide(); // to hide image
$('#img_id').show(); // to show image

Kill a Process by Looking up the Port being used by it from a .BAT

Thank you all, just to add that some process wont close unless the /F force switch is also send with TaskKill. Also with /T switch, all secondary threads of the process will be closed.

C:\>FOR /F "tokens=5 delims= " %P IN ('netstat -a -n -o ^|
 findstr :2002') DO TaskKill.exe /PID %P /T /F

For services it will be necessary to get the name of the service and execute:

sc stop ServiceName

How to set limits for axes in ggplot2 R plots?

Quick note: if you're also using coord_flip() to flip the x and the y axis, you won't be able to set range limits using coord_cartesian() because those two functions are exclusive (see here).

Fortunately, this is an easy fix; set your limits within coord_flip() like so:

p + coord_flip(ylim = c(3,5), xlim = c(100, 400))

This just alters the visible range (i.e. doesn't remove data points).

What is the difference between .yaml and .yml extension?

File extensions do not have any bearing or impact on the content of the file. You can hold YAML content in files with any extension: .yml, .yaml or indeed anything else.

The (rather sparse) YAML FAQ recommends that you use .yaml in preference to .yml, but for historic reasons many Windows programmers are still scared of using extensions with more than three characters and so opt to use .yml instead.

So, what really matters is what is inside the file, rather than what its extension is.

How to remove Left property when position: absolute?

left: initial

This will also set left back to the browser default.

But important to know property: initial is not supported in IE.

C++, What does the colon after a constructor mean?

This is called an initialization list. It is for passing arguments to the constructor of a parent class. Here is a good link explaining it: Initialization Lists in C++

jQuery scrollTop() doesn't seem to work in Safari or Chrome (Windows)

The browser support status is this:

IE8, Firefox, Opera: $("html")

Chrome, Safari: $("body")

So this works:

bodyelem = $.browser.safari ? $("body") : $("html") ;
bodyelem.animate( {scrollTop: 0}, 500 );

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

Description of the possible values:

  • left: No floating elements allowed on the left side
  • right: No floating elements allowed on the right side
  • both: No floating elements allowed on either the left or the right side
  • none: Default. Allows floating elements on both sides
  • inherit: Specifies that the value of the clear property should be inherited from the parent element

Source: w3schools.com

Permission denied for relation

You should:

  1. connect to the database by means of the DBeaver with postgres user
  2. on the left tab open your database
  3. open Roles tab/dropdown
  4. select your user
  5. on the right tab press 'Permissions tab'
  6. press your schema tab
  7. press tables tab/dropdown
  8. select all tables
  9. select all required permissions checkboxes (or press Grant All)
  10. press Save

Illegal Character when trying to compile java code

That's a byte order mark, as everyone says.

javac does not understand the BOM, not even when you try something like

javac -encoding UTF8 Test.java

You need to strip the BOM or convert your source file to another encoding. Notepad++ can convert a single files encoding, I'm not aware of a batch utility on the Windows platform for this.

The java compiler will assume the file is in your platform default encoding, so if you use this, you don't have to specify the encoding.

How to get a Fragment to remove itself, i.e. its equivalent of finish()?

In the Activity/AppCompatActivity:

@Override
public void onBackPressed() {
    if (mDrawerLayout.isDrawerOpen(GravityCompat.START)) {
        // if you want to handle DrawerLayout
        mDrawerLayout.closeDrawer(GravityCompat.START);
    } else {
        if (getFragmentManager().getBackStackEntryCount() == 0) {
            super.onBackPressed();
        } else {
            getFragmentManager().popBackStack();
        }
    }
}

and then call in the fragment:

getActivity().onBackPressed();

or like stated in other answers, call this in the fragment:

getActivity().getSupportFragmentManager().beginTransaction().remove(this).commit();

Git Clone from GitHub over https with two-factor authentication

1st: Get personal access token. https://github.com/settings/tokens
2nd: Put account & the token. Example is here:

$ git push
Username for 'https://github.com':            # Put your GitHub account name
Password for 'https://{USERNAME}@github.com': # Put your Personal access token

Link on how to create a personal access token: https://help.github.com/en/github/authenticating-to-github/creating-a-personal-access-token-for-the-command-line

How to include JavaScript file or library in Chrome console?

var el = document.createElement("script"),
loaded = false;
el.onload = el.onreadystatechange = function () {
  if ((el.readyState && el.readyState !== "complete" && el.readyState !== "loaded") || loaded) {
    return false;
  }
  el.onload = el.onreadystatechange = null;
  loaded = true;
  // done!
};
el.async = true;
el.src = path;
var hhead = document.getElementsByTagName('head')[0];
hhead.insertBefore(el, hhead.firstChild);

How to execute logic on Optional if not present?

For those of you who want to execute a side-effect only if an optional is absent

i.e. an equivalent of ifAbsent() or ifNotPresent() here is a slight modification to the great answers already provided.

myOptional.ifPresentOrElse(x -> {}, () -> {
  // logic goes here
})

HTML select dropdown list

_x000D_
_x000D_
<select>_x000D_
    <option value="" style="display:none">Choose one provider</option>_x000D_
    <option value="1">One</option>_x000D_
    <option value="2">Two</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

This way the user cannot see this option, but it shows in the select box.

OS X: equivalent of Linux's wget

1) on your mac type

nano /usr/bin/wget

2) paste the following in

#!/bin/bash
curl -L $1 -o $2

3) close then make it executable

chmod 777 /usr/bin/wget

That's it.

Should I call Close() or Dispose() for stream objects?

The documentation says that these two methods are equivalent:

StreamReader.Close: This implementation of Close calls the Dispose method passing a true value.

StreamWriter.Close: This implementation of Close calls the Dispose method passing a true value.

Stream.Close: This method calls Dispose, specifying true to release all resources.

So, both of these are equally valid:

/* Option 1, implicitly calling Dispose */
using (StreamWriter writer = new StreamWriter(filename)) { 
   // do something
} 

/* Option 2, explicitly calling Close */
StreamWriter writer = new StreamWriter(filename)
try {
    // do something
}
finally {
    writer.Close();
}

Personally, I would stick with the first option, since it contains less "noise".

python "TypeError: 'numpy.float64' object cannot be interpreted as an integer"

I came here with the same Error, though one with a different origin.

It is caused by unsupported float index in 1.12.0 and newer numpy versions even if the code should be considered as valid.

An int type is expected, not a np.float64

Solution: Try to install numpy 1.11.0

sudo pip install -U numpy==1.11.0.

How can I temporarily disable a foreign key constraint in MySQL?

In phpMyAdmin you can select multiple rows and can then click the delete action. You'll enter a screen which lists the delete queries. It looks like this:

enter image description here

Please uncheck the "Enable foreign key checks" checkbox, and click on Yes to execute them.

This will enable you to delete rows even if there is an ON DELETE restriction constraint.

How to fire an event when v-model changes?

Just to add to the correct answer above, in Vue.JS v1.0 you can write

<a v-on:click="doSomething">

So in this example it would be

 v-on:change="foo"

See: http://v1.vuejs.org/guide/syntax.html#Arguments

How to create tar.gz archive file in Windows?

tar.gz file is just a tar file that's been gzipped. Both tar and gzip are available for windows.

If you like GUIs (Graphical user interface), 7zip can pack with both tar and gzip.

Convert LocalDateTime to LocalDateTime in UTC

you can implement a helper doing something like that :

public static LocalDateTime convertUTCFRtoUTCZ(LocalDateTime dateTime) {
    ZoneId fr = ZoneId.of("Europe/Paris");
    ZoneId utcZ = ZoneId.of("Z");
    ZonedDateTime frZonedTime = ZonedDateTime.of(dateTime, fr);
    ZonedDateTime utcZonedTime = frZonedTime.withZoneSameInstant(utcZ);
    return utcZonedTime.toLocalDateTime();
}

Getting Google+ profile picture url with user_id

Google had changed their policy so the old way for getting the Google profile image will not work now, which was

https://plus.google.com/s2/photos/profile/(user_id)?sz=150

New Way for doing this is

Request URL

https://www.googleapis.com/plus/v1/people/115950284...320?fields=image&key={YOUR_API_KEY}

That will give the Google profile image url in json format as given below

Response :

{
    "image": 
    {
         "url": "https://lh3.googleusercontent.com/-OkM...AANA/ltpH4BFZ2as/photo.jpg?sz=50"
    }
}

More parameters can be found to send with URL which you may need from here

For more detail you can also check the given question where I have answered for same type of problem How to get user image through user id in Google plus?

Create or update mapping in elasticsearch

Please note that there is a mistake in the url provided in this answer:

For a PUT mapping request: the url should be as follows:

http://localhost:9200/name_of_index/_mappings/document_type

and NOT

http://localhost:9200/name_of_index/document_type/_mappings

How to check if an object is an array?

Since I don't like any Object.prototype-calls, I searched for another solution. Especially because the solutions of ChaosPandion won't always work, and the solution of MidnightTortoise with isArray() doesn't work with arrays coming from the DOM (like getElementsByTagName). And finally I found an easy and cross-browser solution, which probably also would have worked with Netscape 4. ;)

It's just these 4 lines (checking any object h):

function isArray(h){
    if((h.length!=undefined&&h[0]!=undefined)||(h.length===0&&h[0]===undefined)){
        return true;
    }
    else{ return false; }
}

I already tested these arrays (all return true):

1) array=d.getElementsByName('some_element'); //'some_element' can be a real or unreal element
2) array=[];
3) array=[10];
4) array=new Array();
5) array=new Array();
   array.push("whatever");

Can anybody confirm that this works for all cases? Or does anybody find a case where my solution don't work?

How to install PHP intl extension in Ubuntu 14.04

install it from terminal

sudo apt-get install php-intl

MySQL Daemon Failed to Start - centos 6

Reference here 2.10.2.1 Troubleshooting Problems Starting the MySQL Server.

1.Find the data directory ,it was configured in my.cnf.

[mysqld]
datadir=/var/lib/mysql

2. Check the err file,it log the error message about why mysql server start failed. the name of err file is related with your hostname.

cd /var/lib/mysql
ll
tail (hostname).err

3.If you find some messages like :

InnoDB: Error: log file ./ib_logfile0 is of different size 0 33554432 bytes
InnoDB: than specified in the .cnf file 0 5242880 bytes!
170513 14:25:22 [ERROR] Plugin 'InnoDB' init function returned error.
170513 14:25:22 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
170513 14:25:22 [ERROR] Unknown/unsupported storage engine: InnoDB
170513 14:25:22 [ERROR] Aborting

then

delete ib_logfile0 and ib_logfile1

, then,

/etc/init.d/mysqld start

How to call another controller Action From a controller in Mvc

This is exactly what I was looking for after finding that RedirectToAction() would not pass complex class objects.

As an example, I want to call the IndexComparison method in the LifeCycleEffectsResults controller and pass it a complex class object named model.

Here is the code that failed:

return RedirectToAction("IndexComparison", "LifeCycleEffectsResults", model);

Worth noting is that Strings, integers, etc were surviving the trip to this controller method, but generic list objects were suffering from what was reminiscent of C memory leaks.

As recommended above, here's the code I replaced it with:

var controller = DependencyResolver.Current.GetService<LifeCycleEffectsResultsController>();

var result = controller.IndexComparison(model);
return result;

All is working as intended now. Thank you for leading the way.

Convert 24 Hour time to 12 Hour plus AM/PM indication Oracle SQL

For the 24-hour time, you need to use HH24 instead of HH.

For the 12-hour time, the AM/PM indicator is written as A.M. (if you want periods in the result) or AM (if you don't). For example:

SELECT invoice_date,
       TO_CHAR(invoice_date, 'DD-MM-YYYY HH24:MI:SS') "Date 24Hr",
       TO_CHAR(invoice_date, 'DD-MM-YYYY HH:MI:SS AM') "Date 12Hr"
  FROM invoices
;

For more information on the format models you can use with TO_CHAR on a date, see http://docs.oracle.com/cd/E16655_01/server.121/e17750/ch4datetime.htm#NLSPG004.

Error:Execution failed for task ':app:transformClassesWithDexForDebug' in android studio

Just worth mentioning that while others suggest tempering with files, I was able to resolve this issue by installing a missing plugin (ionic framework)

Hopefully it helps someone.

cordova plugin add cordova-support-google-services --save

iPhone UILabel text soft shadow

Additionally to IIDan's answer: For some purposes it is necessary to set

label.layer.shouldRasterize = YES

I think this is due to the blend mode that is used to render the shadow. For example I had a dark background and white text on it and wanted to "highlight" the text using a black shadowy glow. It wasn't working until I set this property.

How can you create multiple cursors in Visual Studio Code

You can do the following per the Selection menu:

Screenshot of Selection menu in VS Code

Press/hold Alt+Ctrl+Up Arrow/Alt+Ctrl+Down Arrow as required to create sufficient cursors, then Ctrl+D can be used to expand the selections.

How to add an image to the "drawable" folder in Android Studio?

Copy the image then paste it to drawables in the resource folder of you project in android studio.Make sure the name of your image is not too long and does not have any spacial characters.Then click SRC(source) under properties and look for your image click on it then it will automatically get imported to you image view on you emulator.

Android Studio Gradle: Error:Execution failed for task ':app:processDebugGoogleServices'. > No matching client found for package

check that, in your "google-services.json" file your package_name is available or not

Remove items from one list in another

Here ya go..

    List<string> list = new List<string>() { "1", "2", "3" };
    List<string> remove = new List<string>() { "2" };

    list.ForEach(s =>
        {
            if (remove.Contains(s))
            {
                list.Remove(s);
            }
        });

Loop timer in JavaScript

Here the Automatic loop function with html code. I hope this may be useful for someone.

<!DOCTYPE html>
<html>
<head>
<style>
div {
position: relative;
background-color: #abc;
width: 40px;
height: 40px;
float: left;
margin: 5px;
}
</style>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p><button id="go">Run »</button></p>
<div class="block"></div>
<script>

function test() {
$(".block").animate({left: "+=50", opacity: 1}, 500 );
   setTimeout(mycode, 2000);
};
$( "#go" ).click(function(){
test();
});
</script>
</body>
</html>

Fiddle: DEMO

The module was expected to contain an assembly manifest

Check if the manifest is a valid xml file. I had the same problem by doing a DOS copy command at the end of the build, and it turns out that for some reason I can not understand "copy" was adding a strange character (->) at the end of the manifest files. The problem was solved by adding "/b" switch to force binary copy.

How to get First and Last record from a sql query?

-- Create a function that always returns the first non-NULL item
CREATE OR REPLACE FUNCTION public.first_agg ( anyelement, anyelement )
RETURNS anyelement LANGUAGE SQL IMMUTABLE STRICT AS $$
        SELECT $1;
$$;


-- And then wrap an aggregate around it
CREATE AGGREGATE public.FIRST (
        sfunc    = public.first_agg,
        basetype = anyelement,
        stype    = anyelement
);

-- Create a function that always returns the last non-NULL item
CREATE OR REPLACE FUNCTION public.last_agg ( anyelement, anyelement )
RETURNS anyelement LANGUAGE SQL IMMUTABLE STRICT AS $$
        SELECT $2;
$$;

-- And then wrap an aggregate around it
CREATE AGGREGATE public.LAST (
        sfunc    = public.last_agg,
        basetype = anyelement,
        stype    = anyelement
);

Got it from here: https://wiki.postgresql.org/wiki/First/last_(aggregate)

Returning multiple values from a C++ function

std::pair<int, int> divide(int dividend, int divisor)
{
   // :
   return std::make_pair(quotient, remainder);
}

std::pair<int, int> answer = divide(5,2);
 // answer.first == quotient
 // answer.second == remainder

std::pair is essentially your struct solution, but already defined for you, and ready to adapt to any two data types.

How to determine if a String has non-alphanumeric characters?

Using Apache Commons Lang:

!StringUtils.isAlphanumeric(String)

Alternativly iterate over String's characters and check with:

!Character.isLetterOrDigit(char)

You've still one problem left: Your example string "abcdefà" is alphanumeric, since à is a letter. But I think you want it to be considered non-alphanumeric, right?!

So you may want to use regular expression instead:

String s = "abcdefà";
Pattern p = Pattern.compile("[^a-zA-Z0-9]");
boolean hasSpecialChar = p.matcher(s).find();

Object Required Error in excel VBA

The Set statement is only used for object variables (like Range, Cell or Worksheet in Excel), while the simple equal sign '=' is used for elementary datatypes like Integer. You can find a good explanation for when to use set here.

The other problem is, that your variable g1val isn't actually declared as Integer, but has the type Variant. This is because the Dim statement doesn't work the way you would expect it, here (see example below). The variable has to be followed by its type right away, otherwise its type will default to Variant. You can only shorten your Dim statement this way:

Dim intColumn As Integer, intRow As Integer  'This creates two integers

For this reason, you will see the "Empty" instead of the expected "0" in the Watches window.

Try this example to understand the difference:

Sub Dimming()

  Dim thisBecomesVariant, thisIsAnInteger As Integer
  Dim integerOne As Integer, integerTwo As Integer

  MsgBox TypeName(thisBecomesVariant)  'Will display "Empty"
  MsgBox TypeName(thisIsAnInteger )  'Will display "Integer"
  MsgBox TypeName(integerOne )  'Will display "Integer"
  MsgBox TypeName(integerTwo )  'Will display "Integer"

  'By assigning an Integer value to a Variant it becomes Integer, too
  thisBecomesVariant = 0
  MsgBox TypeName(thisBecomesVariant)  'Will display "Integer"

End Sub

Two further notices on your code:

First remark: Instead of writing

'If g1val is bigger than the value in the current cell
If g1val > Cells(33, i).Value Then
  g1val = g1val   'Don't change g1val
Else
  g1val = Cells(33, i).Value  'Otherwise set g1val to the cell's value
End If

you could simply write

'If g1val is smaller or equal than the value in the current cell
If g1val <= Cells(33, i).Value Then
  g1val = Cells(33, i).Value  'Set g1val to the cell's value 
End If

Since you don't want to change g1val in the other case.

Second remark: I encourage you to use Option Explicit when programming, to prevent typos in your program. You will then have to declare all variables and the compiler will give you a warning if a variable is unknown.

ASP.NET 4.5 has not been registered on the Web server

Resolved it with VS update.

Follow this link (https://blogs.msdn.microsoft.com/webdev/2014/11/11/dialog-box-may-be-displayed-to-users-when-opening-projects-in-microsoft-visual-studio-after-installation-of-microsoft-net-framework-4-6/)

Resolution: Microsoft has published a fix for all impacted versions of Microsoft Visual Studio.

Visual Studio 2013 –

Download Visual Studio 2013 Update 4 For more information on the Visual Studio 2013 Update 4, please refer to: Visual Studio 2013 Update 4 KB Article Visual Studio 2012

An update to address this issue for Microsoft Visual Studio 2012 has been published: KB3002339 To install this update directly from the Microsoft Download Center, here Visual Studio 2010 SP1

An update to address this issue for Microsoft Visual Studio 2010 SP1 has been published: KB3002340 This update is available from Windows Update To install this update directly from the Microsoft Download Center, here

String comparison in Objective-C

You can compare string with below functions.

NSString *first = @"abc";
NSString *second = @"abc";
NSString *third = [[NSString alloc] initWithString:@"abc"];
NSLog(@"%d", (second == third))  
NSLog(@"%d", (first == second)); 
NSLog(@"%d", [first isEqualToString:second]); 
NSLog(@"%d", [first isEqualToString:third]); 

Output will be :-
    0
    1
    1
    1

setup.py examples?

Here you will find the simplest possible example of using distutils and setup.py:

https://docs.python.org/2/distutils/introduction.html#distutils-simple-example

This assumes that all your code is in a single file and tells how to package a project containing a single module.

What underlies this JavaScript idiom: var self = this?

See this article on alistapart.com. (Ed: The article has been updated since originally linked)

self is being used to maintain a reference to the original this even as the context is changing. It's a technique often used in event handlers (especially in closures).

Edit: Note that using self is now discouraged as window.self exists and has the potential to cause errors if you are not careful.

What you call the variable doesn't particularly matter. var that = this; is fine, but there's nothing magic about the name.

Functions declared inside a context (e.g. callbacks, closures) will have access to the variables/function declared in the same scope or above.

For example, a simple event callback:

_x000D_
_x000D_
function MyConstructor(options) {_x000D_
  let that = this;_x000D_
_x000D_
  this.someprop = options.someprop || 'defaultprop';_x000D_
_x000D_
  document.addEventListener('click', (event) => {_x000D_
    alert(that.someprop);_x000D_
  });_x000D_
}_x000D_
_x000D_
new MyConstructor({_x000D_
  someprop: "Hello World"_x000D_
});
_x000D_
_x000D_
_x000D_

How do you wait for input on the same Console.WriteLine() line?

Use Console.Write instead, so there's no newline written:

Console.Write("What is your name? ");
var name = Console.ReadLine();

Including an anchor tag in an ASP.NET MVC Html.ActionLink

My solution will work if you apply the ActionFilter to the Subcategory action method, as long as you always want to redirect the user to the same bookmark:

http://spikehd.blogspot.com/2012/01/mvc3-redirect-action-to-html-bookmark.html

It modifies the HTML buffer and outputs a small piece of javascript to instruct the browser to append the bookmark.

You could modify the javascript to manually scroll, instead of using a bookmark in the URL, of course!

Hope it helps :)

Explanation of JSONB introduced by PostgreSQL

First, hstore is a contrib module, which only allows you to store key => value pairs, where keys and values can only be texts (however values can be sql NULLs too).

Both json & jsonb allows you to store a valid JSON value (defined in its spec).

F.ex. these are valid JSON representations: null, true, [1,false,"string",{"foo":"bar"}], {"foo":"bar","baz":[null]} - hstore is just a little subset compared to what JSON is capable (but if you only need this subset, it's fine).

The only difference between json & jsonb is their storage:

  • json is stored in its plain text format, while
  • jsonb is stored in some binary representation

There are 3 major consequences of this:

  • jsonb usually takes more disk space to store than json (sometimes not)
  • jsonb takes more time to build from its input representation than json
  • json operations take significantly more time than jsonb (& parsing also needs to be done each time you do some operation at a json typed value)

When jsonb will be available with a stable release, there will be two major use cases, when you can easily select between them:

  1. If you only work with the JSON representation in your application, PostgreSQL is only used to store & retrieve this representation, you should use json.
  2. If you do a lot of operations on the JSON value in PostgreSQL, or use indexing on some JSON field, you should use jsonb.

Why do I need to do `--set-upstream` all the time?

By the way, the shortcut to pushing the current branch to a remote with the same name:

$ git push -u origin HEAD

Download history stock prices automatically from yahoo finance in python

It's trivial when you know how:

import yfinance as yf
df = yf.download('CVS', '2015-01-01')
df.to_csv('cvs-health-corp.csv')

If you wish to plot it:

import finplot as fplt
fplt.candlestick_ochl(df[['Open','Close','High','Low']])
fplt.show()

enter image description here

How do I run Redis on Windows?

MS Open Tech recently made a version of Redis available for download on Github. They say that it isn't production ready yet, but keep an eye on it.

Github repo

Download releases as MSIs

Hiding a form and showing another when a button is clicked in a Windows Forms application

Anything after Application.Run( ) will only be executed when the main form closes.

What you could do is handle the VisibleChanged event as follows:

static Form1 form1;
static Form2 form2;

static void Main()
{

    Application.EnableVisualStyles();
    Application.SetCompatibleTextRenderingDefault(false);
    form2 = new Form2();
    form1 = new Form1();
    form2.Hide();
    form1.VisibleChanged += OnForm1Changed;
    Application.Run(form1);

}

static void OnForm1Changed( object sender, EventArgs args )
{
    if ( !form1.Visible )
    {
        form2.Show( );
    }
}

Working with time DURATION, not time of day

The best way I found to resolve this issue was by using a combination of the above. All my cells were entered as a Custom Format to only show "HH:MM" - if I entered in "4:06" (being 4 minutes and 6 seconds) the field would show the numbers I entered correctly - but the data itself would represent HH:MM in the background.

Fortunately time is based on factors of 60 (60 seconds = 60 minutes). So 7H:15M / 60 = 7M:15S - I hope you can see where this is going. Accordingly, if I take my 4:06 and divide by 60 when working with the data (eg. to total up my total time or average time across 100 cells I would use the normal SUM or AVERAGE formulas and then divide by 60 in the formula.

Example =(SUM(A1:A5))/60. If my data was across the 5 time tracking fields was the 4:06, 3:15, 9:12, 2:54, 7:38 (representing MM:SS for us, but the data in the background is actually HH:MM) then when I work out the sum of those 5 fields are, what I want should be 27M:05S but what shows instead is 1D:03H:05M:00S. As mentioned above, 1D:3H:5M divided by 60 = 27M:5S ... which is the sum I am looking for.

Further examples of this are: =(SUM(G:G))/60 and =(AVERAGE(B2:B90)/60) and =MIN(C:C) (this is a direct check so no /60 needed here!).

Note that your "formula" or "calculation" fields (average, total time, etc) MUST have the custom format of MM:SS once you have divided by 60 as Excel's default thinking is in HH:MM (hence this issue). Your data fields where you are entering in your times should need to be changed from "General" or "Number" format to the custom format of HH:MM.

This process is still a little bit cumbersome to use - but it does mean that your data entry is still entered in very easy and is "correctly" displayed on screen as 4:06 (which most people would view as minutes:seconds when under a "Minutes" header). Generally there will only be a couple of fields needing to be used for formulas such as "best time", "average time", "total time" etc when tracking times and they will not usually be changed once the formula is entered so this will be a "one off" process - I use this for my call tracking sheet at work to track "average call", "total call time for day".

How do I get unique elements in this array?

Have you looked at this page?

http://www.mongodb.org/display/DOCS/Aggregation#Aggregation-Distinct

That might save you some time?

eg db.addresses.distinct("zip-code");

are there dictionaries in javascript like python?

Use JavaScript objects. You can access their properties like keys in a dictionary. This is the foundation of JSON. The syntax is similar to Python dictionaries. See: JSON.org

Deleting row from datatable in C#

If you want to remove the entire row from DataTable ,

try this

DataTable dt = new DataTable();  //User DataTable
DataRow[] rows;
rows = dt.Select("Student=' " + id + " ' ");
foreach (DataRow row in rows)
     dt.Rows.Remove(row);

How do I check CPU and Memory Usage in Java?

JMX, The MXBeans (ThreadMXBean, etc) provided will give you Memory and CPU usages.

OperatingSystemMXBean operatingSystemMXBean = (OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean();
operatingSystemMXBean.getSystemCpuLoad();

How to put comments in Django templates

This way can be helpful if you want to comment some Django Template format Code.

{#% include 'file.html' %#} (Right Way)

Following code still executes if commented with HTML Comment.

<!-- {% include 'file.html' %} --> (Wrong Way)

What's the difference between Git Revert, Checkout and Reset?

  • git checkout modifies your working tree,
  • git reset modifies which reference the branch you're on points to,
  • git revert adds a commit undoing changes.

What are invalid characters in XML

For Java folks, Apache has a utility class (StringEscapeUtils) that has a helper method escapeXml which can be used for escaping characters in a string using XML entities.

Replace line break characters with <br /> in ASP.NET MVC Razor view

Applying the DRY principle to Omar's solution, here's an HTML Helper extension:

using System.Web.Mvc;
using System.Text.RegularExpressions;

namespace System.Web.Mvc.Html {
    public static class MyHtmlHelpers {
        public static MvcHtmlString EncodedReplace(this HtmlHelper helper, string input, string pattern, string replacement) {
            return new MvcHtmlString(Regex.Replace(helper.Encode(input), pattern, replacement));
        }
    }
}

Usage (with improved regex):

@Html.EncodedReplace(Model.CommentText, "[\n\r]+", "<br />")

This also has the added benefit of putting less onus on the Razor View developer to ensure security from XSS vulnerabilities.


My concern with Jacob's solution is that rendering the line breaks with CSS breaks the HTML semantics.

Update Rows in SSIS OLEDB Destination

Well, found a solution to my problem; Updating all rows using a SQL query and a SQL Task in SSIS Like Below. May help others if they face same challenge in future.

update Original 
set Original.Vaal= t.vaal 
from Original join (select * from staging1  union   select * from staging2) t 
on Original.id=t.id

How to make a jquery function call after "X" seconds

You can just use the normal setTimeout method in JavaScript.

ie...

setTimeout( function(){ 
    // Do something after 1 second 
  }  , 1000 );

In your example, you might want to use showStickySuccessToast directly.

Hex-encoded String to Byte Array

That should do the trick :

byte[] bytes = toByteArray(Str.toCharArray());

public static byte[] toByteArray(char[] array) {
    return toByteArray(array, Charset.defaultCharset());
}

public static byte[] toByteArray(char[] array, Charset charset) {
    CharBuffer cbuf = CharBuffer.wrap(array);
    ByteBuffer bbuf = charset.encode(cbuf);
    return bbuf.array();
}

ASP.NET Web API session or something?

You can use cookies if the data is small enough and does not present a security concern. The same HttpContext.Current based approach should work.

Request and response HTTP headers can also be used to pass information between service calls.

Set Jackson Timezone for Date deserialization

I am using Jackson 1.9.7 and I found that doing the following does not solve my serialization/deserialization timezone issue:

DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'hh:mm:ss.SSSZ");
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
objectMapper.setDateFormat(dateFormat);

Instead of "2014-02-13T20:09:09.859Z" I get "2014-02-13T08:09:09.859+0000" in the JSON message which is obviously incorrect. I don't have time to step through the Jackson library source code to figure out why this occurs, however I found that if I just specify the Jackson provided ISO8601DateFormat class to the ObjectMapper.setDateFormat method the date is correct.

Except this doesn't put the milliseconds in the format which is what I want so I sub-classed the ISO8601DateFormat class and overrode the format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition) method.

/**
 * Provides a ISO8601 date format implementation that includes milliseconds
 *
 */
public class ISO8601DateFormatWithMillis extends ISO8601DateFormat {

  /**
   * For serialization
   */
  private static final long serialVersionUID = 2672976499021731672L;


  @Override
  public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition)
  {
      String value = ISO8601Utils.format(date, true);
      toAppendTo.append(value);
      return toAppendTo;
  }
}

ROW_NUMBER() in MySQL

SELECT 
    @i:=@i+1 AS iterator, 
    t.*
FROM 
    tablename AS t,
    (SELECT @i:=0) AS foo

HTML5 Canvas background image

Theres a few ways you can do this. You can either add a background to the canvas you are currently working on, which if the canvas isn't going to be redrawn every loop is fine. Otherwise you can make a second canvas underneath your main canvas and draw the background to it. The final way is to just use a standard <img> element placed under the canvas. To draw a background onto the canvas element you can do something like the following:

Live Demo

var canvas = document.getElementById("canvas"),
    ctx = canvas.getContext("2d");

canvas.width = 903;
canvas.height = 657;


var background = new Image();
background.src = "http://www.samskirrow.com/background.png";

// Make sure the image is loaded first otherwise nothing will draw.
background.onload = function(){
    ctx.drawImage(background,0,0);   
}

// Draw whatever else over top of it on the canvas.

MySQL - UPDATE query with LIMIT

You can do it with a LIMIT, just not with a LIMIT and an OFFSET.

Material UI and Grid system

Below is made by purely MUI Grid system,

MUI - Grid Layout

With the code below,

// MuiGrid.js

import React from "react";
import { makeStyles } from "@material-ui/core/styles";
import Paper from "@material-ui/core/Paper";
import Grid from "@material-ui/core/Grid";

const useStyles = makeStyles(theme => ({
  root: {
    flexGrow: 1
  },
  paper: {
    padding: theme.spacing(2),
    textAlign: "center",
    color: theme.palette.text.secondary,
    backgroundColor: "#b5b5b5",
    margin: "10px"
  }
}));

export default function FullWidthGrid() {
  const classes = useStyles();

  return (
    <div className={classes.root}>
      <Grid container spacing={0}>
        <Grid item xs={12}>
          <Paper className={classes.paper}>xs=12</Paper>
        </Grid>
        <Grid item xs={12} sm={6}>
          <Paper className={classes.paper}>xs=12 sm=6</Paper>
        </Grid>
        <Grid item xs={12} sm={6}>
          <Paper className={classes.paper}>xs=12 sm=6</Paper>
        </Grid>
        <Grid item xs={6} sm={3}>
          <Paper className={classes.paper}>xs=6 sm=3</Paper>
        </Grid>
        <Grid item xs={6} sm={3}>
          <Paper className={classes.paper}>xs=6 sm=3</Paper>
        </Grid>
        <Grid item xs={6} sm={3}>
          <Paper className={classes.paper}>xs=6 sm=3</Paper>
        </Grid>
        <Grid item xs={6} sm={3}>
          <Paper className={classes.paper}>xs=6 sm=3</Paper>
        </Grid>
      </Grid>
    </div>
  );
}

↓ CodeSandbox ↓

Edit MUI-Grid system

How to write a shell script that runs some commands as superuser and some commands not as superuser, without having to babysit it?

You should run your entire script as superuser. If you want to run some command as non-superuser, use "-u" option of sudo:

#!/bin/bash

sudo -u username command1
command2
sudo -u username command3
command4

When running as root, sudo doesn't ask for a password.

CKEditor automatically strips classes from div

if you're using ckeditor 4.x you can try

config.allowedContent = true;

if you're using ckeditor 3.x you may be having this issue.

try putting the following line in config.js

config.ignoreEmptyParagraph = false;

Iterating over dictionaries using 'for' loops

Iterating over a dict iterates through its keys in no particular order, as you can see here:

(This is no longer the case in Python 3.6, but note that it's not guaranteed behaviour yet.)

>>> d = {'x': 1, 'y': 2, 'z': 3}
>>> list(d)
['y', 'x', 'z']
>>> d.keys()
['y', 'x', 'z']

For your example, it is a better idea to use dict.items():

>>> d.items()
[('y', 2), ('x', 1), ('z', 3)]

This gives you a list of tuples. When you loop over them like this, each tuple is unpacked into k and v automatically:

for k,v in d.items():
    print(k, 'corresponds to', v)

Using k and v as variable names when looping over a dict is quite common if the body of the loop is only a few lines. For more complicated loops it may be a good idea to use more descriptive names:

for letter, number in d.items():
    print(letter, 'corresponds to', number)

It's a good idea to get into the habit of using format strings:

for letter, number in d.items():
    print('{0} corresponds to {1}'.format(letter, number))

How does facebook, gmail send the real time notification?

One important issue with long polling is error handling. There are two types of errors:

  1. The request might timeout in which case the client should reestablish the connection immediately. This is a normal event in long polling when no messages have arrived.

  2. A network error or an execution error. This is an actual error which the client should gracefully accept and wait for the server to come back on-line.

The main issue is that if your error handler reestablishes the connection immediately also for a type 2 error, the clients would DOS the server.

Both answers with code sample miss this.

function longPoll() { 
        var shouldDelay = false;

        $.ajax({
            url: 'poll.php',
            async: true,            // by default, it's async, but...
            dataType: 'json',       // or the dataType you are working with
            timeout: 10000,          // IMPORTANT! this is a 10 seconds timeout
            cache: false

        }).done(function (data, textStatus, jqXHR) {
             // do something with data...

        }).fail(function (jqXHR, textStatus, errorThrown ) {
            shouldDelay = textStatus !== "timeout";

        }).always(function() {
            // in case of network error. throttle otherwise we DOS ourselves. If it was a timeout, its normal operation. go again.
            var delay = shouldDelay ? 10000: 0;
            window.setTimeout(longPoll, delay);
        });
}
longPoll(); //fire first handler

Binning column with python pandas

You can use pandas.cut:

bins = [0, 1, 5, 10, 25, 50, 100]
df['binned'] = pd.cut(df['percentage'], bins)
print (df)
   percentage     binned
0       46.50   (25, 50]
1       44.20   (25, 50]
2      100.00  (50, 100]
3       42.12   (25, 50]

bins = [0, 1, 5, 10, 25, 50, 100]
labels = [1,2,3,4,5,6]
df['binned'] = pd.cut(df['percentage'], bins=bins, labels=labels)
print (df)
   percentage binned
0       46.50      5
1       44.20      5
2      100.00      6
3       42.12      5

Or numpy.searchsorted:

bins = [0, 1, 5, 10, 25, 50, 100]
df['binned'] = np.searchsorted(bins, df['percentage'].values)
print (df)
   percentage  binned
0       46.50       5
1       44.20       5
2      100.00       6
3       42.12       5

...and then value_counts or groupby and aggregate size:

s = pd.cut(df['percentage'], bins=bins).value_counts()
print (s)
(25, 50]     3
(50, 100]    1
(10, 25]     0
(5, 10]      0
(1, 5]       0
(0, 1]       0
Name: percentage, dtype: int64

s = df.groupby(pd.cut(df['percentage'], bins=bins)).size()
print (s)
percentage
(0, 1]       0
(1, 5]       0
(5, 10]      0
(10, 25]     0
(25, 50]     3
(50, 100]    1
dtype: int64

By default cut return categorical.

Series methods like Series.value_counts() will use all categories, even if some categories are not present in the data, operations in categorical.

PHP Fatal error: Call to undefined function json_decode()

Solution for LAMP users:

apt-get install php5-json
service apache2 restart

Source

Split string into string array of single characters

Convert the message to a character array, then use a for loop to change it to a string

string message = "This Is A Test";
string[] result = new string[message.Length];
char[] temp = new char[message.Length];

temp = message.ToCharArray();

for (int i = 0; i < message.Length - 1; i++)
{
     result[i] = Convert.ToString(temp[i]);
}

How to enable GZIP compression in IIS 7.5

If anyone runs across this and is looking for a bit more up-to-date answer or copy-paste answer or answer targeting multiple versions than JC Raja's post, here's what I've found:

Google's got a pretty solid, easy-to-understand introduction to how this works and what is advantageous and not. https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/optimize-encoding-and-transfer They recommend the HTML5 Boilerplate project, which has solutions for different versions of IIS:

  • .NET version 3
  • .NET version 4
  • .NET version 4.5 / MVC 5

Available here: https://github.com/h5bp/server-configs-iis They have web.configs that you can copy and paste changes from theirs to yours and see the changes, much easier than digging through a bunch of blog posts.

Here's the web.config settings for .NET version 4.5: https://github.com/h5bp/server-configs-iis/blob/master/dotnet%204.5/MVC5/Web.config

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <appSettings>
    <add key="webpages:Version" value="3.0.0.0" />
    <add key="webpages:Enabled" value="false" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />
  </appSettings>
  <system.web>
    <!--
            Set compilation debug="true" to insert debugging
            symbols into the compiled page. Because this
            affects performance, set this value to true only
            during development.
    -->
    <compilation debug="true" targetFramework="4.5" />

    <!-- Security through obscurity, removes  X-AspNet-Version HTTP header from the response -->
    <!-- Allow zombie DOS names to be captured by ASP.NET (/con, /com1, /lpt1, /aux, /prt, /nul, etc) -->
    <httpRuntime targetFramework="4.5" requestValidationMode="2.0" requestPathInvalidCharacters="" enableVersionHeader="false" relaxedUrlToFileSystemMapping="true" />

    <!-- httpCookies httpOnlyCookies setting defines whether cookies 
             should be exposed to client side scripts
             false (Default): client side code can access cookies
             true: client side code cannot access cookies
             Require SSL is situational, you can also define the 
             domain of cookies with optional "domain" property -->
    <httpCookies httpOnlyCookies="true" requireSSL="false" />

    <trace writeToDiagnosticsTrace="false" enabled="false" pageOutput="false" localOnly="true" />
  </system.web>


  <system.webServer>
    <!-- GZip static file content.  Overrides the server default which only compresses static files over 2700 bytes -->
    <httpCompression directory="%SystemDrive%\websites\_compressed" minFileSizeForComp="1024">
      <scheme name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" />
      <staticTypes>
        <add mimeType="text/*" enabled="true" />
        <add mimeType="message/*" enabled="true" />
        <add mimeType="application/javascript" enabled="true" />
        <add mimeType="application/json" enabled="true" />
        <add mimeType="*/*" enabled="false" />
      </staticTypes>
    </httpCompression>

    <httpErrors existingResponse="PassThrough" errorMode="Custom">
      <!-- Catch IIS 404 error due to paths that exist but shouldn't be served (e.g. /controllers, /global.asax) or IIS request filtering (e.g. bin, web.config, app_code, app_globalresources, app_localresources, app_webreferences, app_data, app_browsers) -->
      <remove statusCode="404" subStatusCode="-1" />
      <error statusCode="404" subStatusCode="-1" path="/notfound" responseMode="ExecuteURL" />
      <remove statusCode="500" subStatusCode="-1" />
      <error statusCode="500" subStatusCode="-1" path="/error" responseMode="ExecuteURL" />
    </httpErrors>

    <directoryBrowse enabled="false" />
    <validation validateIntegratedModeConfiguration="false" />

    <!-- Microsoft sets runAllManagedModulesForAllRequests to true by default
             You should handle this according to need but consider the performance hit.
             Good source of reference on this matter: http://www.west-wind.com/weblog/posts/2012/Oct/25/Caveats-with-the-runAllManagedModulesForAllRequests-in-IIS-78
        -->
    <modules runAllManagedModulesForAllRequests="false" />

    <urlCompression doStaticCompression="true" doDynamicCompression="true" />
    <staticContent>
      <!-- Set expire headers to 30 days for static content-->
      <clientCache cacheControlMode="UseMaxAge" cacheControlMaxAge="30.00:00:00" />
      <!-- use utf-8 encoding for anything served text/plain or text/html -->
      <remove fileExtension=".css" />
      <mimeMap fileExtension=".css" mimeType="text/css" />
      <remove fileExtension=".js" />
      <mimeMap fileExtension=".js" mimeType="text/javascript" />
      <remove fileExtension=".json" />
      <mimeMap fileExtension=".json" mimeType="application/json" />
      <remove fileExtension=".rss" />
      <mimeMap fileExtension=".rss" mimeType="application/rss+xml; charset=UTF-8" />
      <remove fileExtension=".html" />
      <mimeMap fileExtension=".html" mimeType="text/html; charset=UTF-8" />
      <remove fileExtension=".xml" />
      <mimeMap fileExtension=".xml" mimeType="application/xml; charset=UTF-8" />
      <!-- HTML5 Audio/Video mime types-->
      <remove fileExtension=".mp3" />
      <mimeMap fileExtension=".mp3" mimeType="audio/mpeg" />
      <remove fileExtension=".mp4" />
      <mimeMap fileExtension=".mp4" mimeType="video/mp4" />
      <remove fileExtension=".ogg" />
      <mimeMap fileExtension=".ogg" mimeType="audio/ogg" />
      <remove fileExtension=".ogv" />
      <mimeMap fileExtension=".ogv" mimeType="video/ogg" />
      <remove fileExtension=".webm" />
      <mimeMap fileExtension=".webm" mimeType="video/webm" />
      <!-- Proper svg serving. Required for svg webfonts on iPad -->
      <remove fileExtension=".svg" />
      <mimeMap fileExtension=".svg" mimeType="image/svg+xml" />
      <remove fileExtension=".svgz" />
      <mimeMap fileExtension=".svgz" mimeType="image/svg+xml" />
      <!-- HTML4 Web font mime types -->
      <!-- Remove default IIS mime type for .eot which is application/octet-stream -->
      <remove fileExtension=".eot" />
      <mimeMap fileExtension=".eot" mimeType="application/vnd.ms-fontobject" />
      <remove fileExtension=".ttf" />
      <mimeMap fileExtension=".ttf" mimeType="application/x-font-ttf" />
      <remove fileExtension=".ttc" />
      <mimeMap fileExtension=".ttc" mimeType="application/x-font-ttf" />
      <remove fileExtension=".otf" />
      <mimeMap fileExtension=".otf" mimeType="font/opentype" />
      <remove fileExtension=".woff" />
      <mimeMap fileExtension=".woff" mimeType="application/font-woff" />
      <remove fileExtension=".crx" />
      <mimeMap fileExtension=".crx" mimeType="application/x-chrome-extension" />
      <remove fileExtension=".xpi" />
      <mimeMap fileExtension=".xpi" mimeType="application/x-xpinstall" />
      <remove fileExtension=".safariextz" />
      <mimeMap fileExtension=".safariextz" mimeType="application/octet-stream" />
      <!-- Flash Video mime types-->
      <remove fileExtension=".flv" />
      <mimeMap fileExtension=".flv" mimeType="video/x-flv" />
      <remove fileExtension=".f4v" />
      <mimeMap fileExtension=".f4v" mimeType="video/mp4" />
      <!-- Assorted types -->
      <remove fileExtension=".ico" />
      <mimeMap fileExtension=".ico" mimeType="image/x-icon" />
      <remove fileExtension=".webp" />
      <mimeMap fileExtension=".webp" mimeType="image/webp" />
      <remove fileExtension=".htc" />
      <mimeMap fileExtension=".htc" mimeType="text/x-component" />
      <remove fileExtension=".vcf" />
      <mimeMap fileExtension=".vcf" mimeType="text/x-vcard" />
      <remove fileExtension=".torrent" />
      <mimeMap fileExtension=".torrent" mimeType="application/x-bittorrent" />
      <remove fileExtension=".cur" />
      <mimeMap fileExtension=".cur" mimeType="image/x-icon" />
      <remove fileExtension=".webapp" />
      <mimeMap fileExtension=".webapp" mimeType="application/x-web-app-manifest+json; charset=UTF-8" />
    </staticContent>
    <httpProtocol>
      <customHeaders>

        <!--#### SECURITY Related Headers ###
            More information: https://www.owasp.org/index.php/List_of_useful_HTTP_headers
        -->
        <!--
                # Access-Control-Allow-Origin
                The 'Access Control Allow Origin' HTTP header is used to control which
                sites are allowed to bypass same-origin policies and send cross-origin requests.

                Secure configuration: Either do not set this header or return the 'Access-Control-Allow-Origin'
                header restricting it to only a trusted set of sites.
                http://enable-cors.org/

                <add name="Access-Control-Allow-Origin" value="*" />
                -->

        <!--
                # Cache-Control
                The 'Cache-Control' response header controls how pages can be cached
                either by proxies or the user's browser.
                This response header can provide enhanced privacy by not caching
                sensitive pages in the user's browser cache.

                <add name="Cache-Control" value="no-store, no-cache"/>
                -->

        <!--
                # Strict-Transport-Security
                The HTTP Strict Transport Security header is used to control
                if the browser is allowed to only access a site over a secure connection
                and how long to remember the server response for, forcing continued usage.
                Note* Currently a draft standard which only Firefox and Chrome support. But is supported by sites like PayPal.
                <add name="Strict-Transport-Security" value="max-age=15768000"/>
                -->

        <!--
                # X-Frame-Options
                The X-Frame-Options header indicates whether a browser should be allowed
                to render a page within a frame or iframe.
                The valid options are DENY (deny allowing the page to exist in a frame)
                or SAMEORIGIN (allow framing but only from the originating host)
                Without this option set, the site is at a higher risk of click-jacking.

                <add name="X-Frame-Options" value="SAMEORIGIN" />
                -->

        <!--
                # X-XSS-Protection
                The X-XSS-Protection header is used by Internet Explorer version 8+
                The header instructs IE to enable its inbuilt anti-cross-site scripting filter.
                If enabled, without 'mode=block', there is an increased risk that
                otherwise, non-exploitable cross-site scripting vulnerabilities may potentially become exploitable

                <add name="X-XSS-Protection" value="1; mode=block"/>
                -->

        <!--    
                # MIME type sniffing security protection
                Enabled by default as there are very few edge cases where you wouldn't want this enabled.
                Theres additional reading below; but the tldr, it reduces the ability of the browser (mostly IE) 
                being tricked into facilitating driveby attacks.
                http://msdn.microsoft.com/en-us/library/ie/gg622941(v=vs.85).aspx
                http://blogs.msdn.com/b/ie/archive/2008/07/02/ie8-security-part-v-comprehensive-protection.aspx
        -->
        <add name="X-Content-Type-Options" value="nosniff" />

        <!-- A little extra security (by obscurity), removings fun but adding your own is better -->
        <remove name="X-Powered-By" />
        <add name="X-Powered-By" value="My Little Pony" />

        <!--
                 With Content Security Policy (CSP) enabled (and a browser that supports it (http://caniuse.com/#feat=contentsecuritypolicy),
         you can tell the browser that it can only download content from the domains you explicitly allow
         CSP can be quite difficult to configure, and cause real issues if you get it wrong
         There is website that helps you generate a policy here http://cspisawesome.com/
         <add name="Content-Security-Policy" "default-src 'self'; style-src 'self' 'unsafe-inline'; script-src 'self' https://www.google-analytics.com;" />
                -->

        <!--//#### SECURITY Related Headers ###-->

        <!--
                Force the latest IE version, in various cases when it may fall back to IE7 mode
                github.com/rails/rails/commit/123eb25#commitcomment-118920
                Use ChromeFrame if it's installed for a better experience for the poor IE folk
                -->
        <add name="X-UA-Compatible" value="IE=Edge,chrome=1" />
        <!--
                Allow cookies to be set from iframes (for IE only)
                If needed, uncomment and specify a path or regex in the Location directive

                <add name="P3P" value="policyref=&quot;/w3c/p3p.xml&quot;, CP=&quot;IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT&quot;" />
                -->

      </customHeaders>
    </httpProtocol>

    <!--
        <rewrite>
            <rules>

            Remove/force the WWW from the URL.
            Requires IIS Rewrite module http://learn.iis.net/page.aspx/460/using-the-url-rewrite-module/
            Configuration lifted from http://nayyeri.net/remove-www-prefix-from-urls-with-url-rewrite-module-for-iis-7-0

            NOTE* You need to install the IIS URL Rewriting extension (Install via the Web Platform Installer)
            http://www.microsoft.com/web/downloads/platform.aspx

            ** Important Note
            using a non-www version of a webpage will set cookies for the whole domain making cookieless domains
            (eg. fast CD-like access to static resources like CSS, js, and images) impossible.

            # IMPORTANT: THERE ARE TWO RULES LISTED. NEVER USE BOTH RULES AT THE SAME TIME!

                <rule name="Remove WWW" stopProcessing="true">
                    <match url="^(.*)$" />
                    <conditions>
                        <add input="{HTTP_HOST}" pattern="^(www\.)(.*)$" />
                    </conditions>
                    <action type="Redirect" url="http://example.com{PATH_INFO}" redirectType="Permanent" />
                </rule>
                <rule name="Force WWW" stopProcessing="true">
                    <match url=".*" />
                    <conditions>
                        <add input="{HTTP_HOST}" pattern="^example.com$" />
                    </conditions>
                    <action type="Redirect" url="http://www.example.com/{R:0}" redirectType="Permanent" />
                </rule>


                # E-TAGS
                E-Tags are actually quite useful in cache management especially if you have a front-end caching server such as Varnish. http://en.wikipedia.org/wiki/HTTP_ETag / http://developer.yahoo.com/performance/rules.html#etags
                But in load balancing and simply most cases ETags are mishandled in IIS, and it can be advantageous to remove them.
        # removed as in https://stackoverflow.com/questions/7947420/iis-7-5-remove-etag-headers-from-response

        <rewrite>
           <outboundRules>
              <rule name="Remove ETag">
                 <match serverVariable="RESPONSE_ETag" pattern=".+" />
                 <action type="Rewrite" value="" />
              </rule>
           </outboundRules>
        </rewrite>

            -->
    <!--
            ### Built-in filename-based cache busting

            In a managed language such as .net, you should really be using the internal bundler for CSS + js
            or get cassette or similar.

            If you're not using the build script to manage your filename version revving,
            you might want to consider enabling this, which will route requests for
            /css/style.20110203.css to /css/style.css

            To understand why this is important and a better idea than all.css?v1231,
            read: github.com/h5bp/html5-boilerplate/wiki/Version-Control-with-Cachebusting

                <rule name="Cachebusting">
                    <match url="^(.+)\.\d+(\.(js|css|png|jpg|gif)$)" />
                    <action type="Rewrite" url="{R:1}{R:2}" />
                </rule>

            </rules>
        </rewrite>-->

  </system.webServer>

  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-5.0.0.0" newVersion="5.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Optimization" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="1.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.5.2.14234" newVersion="1.5.2.14234" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

Edit: One update if you need Gzip compression on WebAPI responses. I wasn't aware our WebAPI wasn't returning Gzipped responses until recently and scratched my head for a while because we had dynamic and static compression turned on in web.config. We looked at writing our own compression services and response handlers (still on WebAPI 2 not on .NET Core where it's easier now), but that was too cumbersome for what seemed like something we should just be able to turn on.

(If you're interested here's what we were looking at for our own compression service https://krzysztofjakielaszek.com/2017/03/26/webapi2-response-compression-gzip-brotli-deflate/ EDIT: Link is now offline, but you can view the code/content here: https://web.archive.org/web/20190608161201/https://krzysztofjakielaszek.com/2017/03/26/webapi2-response-compression-gzip-brotli-deflate/ )

Instead, we found this great post by Ben Foster (http://benfoster.io/blog/aspnet-web-api-compression) If you can modify applicationHost.config (running your own servers), you can pop that config file open and add the mimeTypes you want to compress (I pulled the relevant ones based on what our API was returning to clients from our Web.Config). Save that file, IIS will pickup your changes, recycle app pools, and your WebAPI will start returning gzip compressed responses to clients who request it.

If you don't see gzipped responses, check the response content type with Fiddler or Chrome/Firefox Dev Tools, and ensure it matches what you added. I had to change the view mode (use large request rows) in Chrome Dev Tools to ensure it showed the total size vs transferred size. If everything validates, try rebooting the server once to just ensure it was properly applied. I did have one syntax error where when I opened up the site in IIS, IIS poppped open a message about a parsing error that I had to fix in the config file.

<httpCompression directory="%TEMP%\iisexpress\IIS Temporary Compressed Files">
    <scheme name="gzip" dll="%IIS_BIN%\gzip.dll" />
    <dynamicTypes>
        ...

        <!-- compress JSON responses from Web API -->           
        <add mimeType="application/json" enabled="true" /> 

        ...
    </dynamicTypes>
    <staticTypes>
        ...
    </staticTypes>
</httpCompression>

Add Keypair to existing EC2 instance

You can just add a new key to the instance by the following command:

ssh-copy-id -i ~/.ssh/id_rsa.pub domain_alias

You can configure domain_alias in ~/.ssh config

host domain_alias
  User ubuntu
  Hostname domain.com
  IdentityFile ~/.ssh/ec2.pem

Ruby on Rails: Where to define global constants?

Some options:

Using a constant:

class Card
  COLOURS = ['white', 'blue', 'black', 'red', 'green', 'yellow'].freeze
end

Lazy loaded using class instance variable:

class Card
  def self.colours
    @colours ||= ['white', 'blue', 'black', 'red', 'green', 'yellow'].freeze
  end
end

If it is a truly global constant (avoid global constants of this nature, though), you could also consider putting a top-level constant in config/initializers/my_constants.rb for example.

How do you plot bar charts in gnuplot?

plot "data.dat" using 2: xtic(1) with histogram

Here data.dat contains data of the form

title 1
title2 3
"long title" 5

Can I use library that used android support with Androidx projects.

Add the lines in the gradle.properties file

android.useAndroidX=true
android.enableJetifier=true

enter image description here enter image description here Refer also https://developer.android.com/jetpack/androidx

How to get status code from webclient?

You can check if the error is of type WebException and then inspect the response code;

if (e.Error.GetType().Name == "WebException")
{
   WebException we = (WebException)e.Error;
   HttpWebResponse response = (System.Net.HttpWebResponse)we.Response;
   if (response.StatusCode==HttpStatusCode.NotFound)
      System.Diagnostics.Debug.WriteLine("Not found!");
}

or

try
{
    // send request
}
catch (WebException e)
{
    // check e.Status as above etc..
}

Elasticsearch query to return all records

elasticsearch(ES) supports both a GET or a POST request for getting the data from the ES cluster index.

When we do a GET:

http://localhost:9200/[your index name]/_search?size=[no of records you want]&q=*:*

When we do a POST:

http://localhost:9200/[your_index_name]/_search
{
  "size": [your value] //default 10
  "from": [your start index] //default 0
  "query":
   {
    "match_all": {}
   }
}   

I would suggest to use a UI plugin with elasticsearch http://mobz.github.io/elasticsearch-head/ This will help you get a better feeling of the indices you create and also test your indices.

How to change row color in datagridview?

You can Change Backcolor row by row using your condition.and this function call after applying Datasource of DatagridView.

Here Is the function for that. Simply copy that and put it after Databind

private void ChangeRowColor()
{
    for (int i = 0; i < gvItem.Rows.Count; i++)
    {
        if (BindList[i].MainID == 0 && !BindList[i].SchemeID.HasValue)
            gvItem.Rows[i].DefaultCellStyle.BackColor = ColorTranslator.FromHtml("#C9CADD");
        else if (BindList[i].MainID > 0 && !BindList[i].SchemeID.HasValue)
            gvItem.Rows[i].DefaultCellStyle.BackColor = ColorTranslator.FromHtml("#DDC9C9");
        else if (BindList[i].MainID > 0)
            gvItem.Rows[i].DefaultCellStyle.BackColor = ColorTranslator.FromHtml("#D5E8D7");
        else
            gvItem.Rows[i].DefaultCellStyle.BackColor = Color.White;
    }
}

How do I format a number with commas in T-SQL?

SELECT REPLACE(CONVERT(varchar(20), (CAST(9876543 AS money)), 1), '.00', '')

output= 9,876,543

and you can replace 9876543 by your column name.

Git Bash won't run my python files?

Tried multiple of these, I switched to Cygwin instead which fixed python and some other problems I was having on Windows:

https://www.cygwin.com/

Push eclipse project to GitHub with EGit

I have the same issue and solved it by reading this post, while solving it, I hitted a problem: auth failed.

And I finally solved it by using a ssh key way to authorize myself. I found the EGit offical guide very useful and I configured the ssh way successfully by refer to the Eclipse SSH Configuration section in the link provided.

Hope it helps.

How can I center text (horizontally and vertically) inside a div block?

Common techniques as of 2014:


  • Approach 1 - transform translateX/translateY:

    Example Here / Full Screen Example

    In supported browsers (most of them), you can use top: 50%/left: 50% in combination with translateX(-50%) translateY(-50%) to dynamically vertically/horizontally center the element.

    .container {
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translateX(-50%) translateY(-50%);
    }
    

  • Approach 2 - Flexbox method:

    Example Here / Full Screen Example

    In supported browsers, set the display of the targeted element to flex and use align-items: center for vertical centering and justify-content: center for horizontal centering. Just don't forget to add vendor prefixes for additional browser support (see example).

    html, body, .container {
        height: 100%;
    }
    .container {
        display: flex;
        align-items: center;
        justify-content: center;
    }
    

  • Approach 3 - table-cell/vertical-align: middle:

    Example Here / Full Screen Example

    In some cases, you will need to ensure that the html/body element's height is set to 100%.

    For vertical alignment, set the parent element's width/height to 100% and add display: table. Then for the child element, change the display to table-cell and add vertical-align: middle.

    For horizontal centering, you could either add text-align: center to center the text and any other inline children elements. Alternatively, you could use margin: 0 auto assuming the element is block level.

    html, body {
        height: 100%;
    }
    .parent {
        width: 100%;
        height: 100%;
        display: table;
        text-align: center;
    }
    .parent > .child {
        display: table-cell;
        vertical-align: middle;
    }
    

  • Approach 4 - Absolutely positioned 50% from the top with displacement:

    Example Here / Full Screen Example

    This approach assumes that the text has a known height - in this instance, 18px. Just absolutely position the element 50% from the top, relative to the parent element. Use a negative margin-top value that is half of the element's known height, in this case - -9px.

    html, body, .container {
        height: 100%;
    }
    .container {
        position: relative;
        text-align: center;
    }
    .container > p {
        position: absolute;
        top: 50%;
        left: 0;
        right: 0;
        margin-top: -9px;
    }
    

  • Approach 5 - The line-height method (Least flexible - not suggested):

    Example Here

    In some cases, the parent element will have a fixed height. For vertical centering, all you have to do is set a line-height value on the child element equal to the fixed height of the parent element.

    Though this solution will work in some cases, it's worth noting that it won't work when there are multiple lines of text - like this.

    .parent {
        height: 200px;
        width: 400px;
        text-align: center;
    }
    .parent > .child {
        line-height: 200px;
    }
    

Methods 4 and 5 aren't the most reliable. Go with one of the first 3.

How do I link a JavaScript file to a HTML file?

this is demo code but it will help 

<!DOCTYPE html>
<html>
<head>
<title>APITABLE 3</title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script>


$(document).ready(function(){

$.ajax({
    type: "GET",
    url: "https://reqres.in/api/users/",

    data: '$format=json',

    dataType: 'json',
    success: function (data) {
 $.each(data.data,function(d,results){
     console.log(data);

 $("#apiData").append(
                        "<tr>"
                          +"<td>"+results.first_name+"</td>"
                          +"<td>"+results.last_name+"</td>"
                          +"<td>"+results.id+"</td>"
                          +"<td>"+results.email+"</td>"
  +"<td>"+results.bentrust+"</td>"
                        +"</tr>" )
                    })
 } 

});

});


</script>
</head>
<body>


    <table id="apiTable">

        <thead>
            <tr>
            <th>Id</th>
            <br>
            <th>Email</th>
            <br>
            <th>Firstname</th>
            <br>
            <th>Lastname</th>
        </tr>
        </thead>
        <tbody id="apiData"></tbody>    





</body>
</html> 

SQL Server - inner join when updating

This should do it:

UPDATE ProductReviews
SET    ProductReviews.status = '0'
FROM   ProductReviews
       INNER JOIN products
         ON ProductReviews.pid = products.id
WHERE  ProductReviews.id = '17190'
       AND products.shopkeeper = '89137'

How to print an exception in Python 3?

I've use this :

except (socket.timeout, KeyboardInterrupt) as e:
    logging.debug("Exception : {}".format(str(e.__str__).split(" ")[3]))
    break

Let me know if it does not work for you !!

No visible cause for "Unexpected token ILLEGAL"

When running OS X, the filesystem creates hidden forks of basically all your files, if they are on a hard drive that doesn't support HFS+. This can sometimes (happened to me just now) lead to your JavaScript engine tries to run the data-fork instead of the code you intend it to run. When this happens, you will also receive

SyntaxError: Unexpected token ILLEGAL

because the data fork of your file will contain the Unicode U+200B character. Removing the data fork file will make your script run your actual, intended code, instead of a binary data fork of your code.

.whatever : These files are created on volumes that don't natively support full HFS file characteristics (e.g. ufs volumes, Windows fileshares, etc). When a Mac file is copied to such a volume, its data fork is stored under the file's regular name, and the additional HFS information (resource fork, type & creator codes, etc) is stored in a second file (in AppleDouble format), with a name that starts with ".". (These files are, of course, invisible as far as OS-X is concerned, but not to other OS's; this can sometimes be annoying...)

error code 1292 incorrect date value mysql

I happened to be working in localhost , in windows 10, using WAMP, as it turns out, Wamp has a really accessible configuration interface to change the MySQL configuration. You just need to go to the Wamp panel, then to MySQL, then to settings and change the mode to sql-mode: none.(essentially disabling the strict mode) The following picture illustrates this.

enter image description here

Unable to start MySQL server

You should start by checking the error log and/or the startup message log when managing the instance using MySQL Workbench. There could be clues as to what is going wrong, which may be different than this scenario.

When I had this issue, it was because I used a space in the service name during installation. While it is technically valid, you should not do that. It seems that the MySQL Installer (and MySQL Notifier) does not put the name in quotes which causes it to use an incorrect service name later on. There are two ways to fix the problem (all commands should be run from an elevated command prompt).

Reinstall the server

The first is to simply reinstall MySQL Server 5.6 using the default, no-space service name MySQL56.

The installer uses the same value for the service name and service display name. The name that I had originally specified was for a display name, when it should have been a simple service name. After installation, if you so choose, the display name can safely be changed to use spaces and other characters by using:

sc config MySQL56 DisplayName= "MySQL 5.6"

Recreate the service

If you don't want to reinstall the server however, you will have to recreate the service. Start by removing the old service:

mysqld --remove "service_name"

Now install the replacement. You can use --install to create a service that starts with the system automatically, or --install-manual to create a service that requires you to start it.

mysqld --install-manual "service_name" --local-service --defaults-file="C:\path\to\mysql\my.ini"

This creates a service that runs as the LocalService account which presents anonymous credentials on the network however. Under most circumstances this is fine, but if you want to use the NetworkService account (which is what the installer creates the service as) you can change it using the Services administrative tool.

Convert String to Type in C#

Try:

Type type = Type.GetType(inputString); //target type
object o = Activator.CreateInstance(type); // an instance of target type
YourType your = (YourType)o;

Jon Skeet is right as usually :)

Update: You can specify assembly containing target type in various ways, as Jon mentioned, or:

YourType your = (YourType)Activator.CreateInstance("AssemblyName", "NameSpace.MyClass");

How to serialize Joda DateTime with Jackson JSON processor?

I'm using Java 8 and this worked for me.

Add the dependency on pom.xml

<dependency>
    <groupId>com.fasterxml.jackson.datatype</groupId>
    <artifactId>jackson-datatype-jsr310</artifactId>
    <version>2.4.0</version>
</dependency>

and add JodaModule on your ObjectMapper

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JodaModule());

How to create Windows EventLog source from command line?

However the cmd/batch version works you can run into an issue when you want to define an eventID which is higher then 1000. For event creation with an eventID of 1000+ i'll use powershell like this:

$evt=new-object System.Diagnostics.Eventlog(“Define Logbook”)
$evt.Source=”Define Source”
$evtNumber=Define Eventnumber
$evtDescription=”Define description”
$infoevent=[System.Diagnostics.EventLogEntryType]::Define error level
$evt.WriteEntry($evtDescription,$infoevent,$evtNumber) 

Sample:

$evt=new-object System.Diagnostics.Eventlog(“System”)
$evt.Source=”Tcpip”
$evtNumber=4227
$evtDescription=”This is a Test Event”
$infoevent=[System.Diagnostics.EventLogEntryType]::Warning
$evt.WriteEntry($evtDescription,$infoevent,$evtNumber)

do <something> N times (declarative syntax)

TypeScript Implementation:

For those of you who are interested in how to implement String.times and Number.times in a way that is type safe and works with the thisArg, here ya go:

declare global {
    interface Number {
        times: (callbackFn: (iteration: number) => void, thisArg?: any) => void;
    }
    interface String {
        times: (callbackFn: (iteration: number) => void, thisArg?: any) => void;
    }
}

Number.prototype.times = function (callbackFn, thisArg) {
    const num = this.valueOf()
    if (typeof callbackFn !== "function" ) {
        throw new TypeError("callbackFn is not a function")
    }
    if (num < 0) {
        throw new RangeError('Must not be negative')
    }
    if (!isFinite(num)) {
        throw new RangeError('Must be Finite')
    }
    if (isNaN(num)) {
        throw new RangeError('Must not be NaN')
    }

    [...Array(num)].forEach((_, i) => callbackFn.bind(thisArg, i + 1)())
    // Other elegant solutions
    // new Array<null>(num).fill(null).forEach(() => {})
    // Array.from({length: num}).forEach(() => {})
}

String.prototype.times = function (callbackFn, thisArg) {
    let num = parseInt(this.valueOf())
    if (typeof callbackFn !== "function" ) {
        throw new TypeError("callbackFn is not a function")
    }
    if (num < 0) {
        throw new RangeError('Must not be negative')
    }
    if (!isFinite(num)) {
        throw new RangeError('Must be Finite')
    }
    // num is NaN if `this` is an empty string 
    if (isNaN(num)) {
        num = 0
    }

    [...Array(num)].forEach((_, i) => callbackFn.bind(thisArg, i + 1)())
    // Other elegant solutions
    // new Array<null>(num).fill(null).forEach(() => {})
    // Array.from({length: num}).forEach(() => {})
}

A link to the TypeScript Playground with some examples can be found here

This post implements solutions posted by: Andreas Bergström, vinyll, Ozay Duman, & SeregPie

Netbeans - Error: Could not find or load main class

Possible Fixes:

Fix 1

  1. Go to project properties (right click on the folder of your project in netbeans)
  2. On left tab where it shows the categories, click on the "Run" selection
  3. Then click on Browse to find the Main class you use on your project

Fix 2

  1. Go to C:\Users\name\AppData\Local\Netbeans
  2. delete the Cache folder.
  3. Rebuild and Run

Fix 3 Download most recent version of Netbeans

Fix 4 Download most recent version of JDK and configure Netbeans to use that

How can I check if a string is null or empty in PowerShell?

You can use the IsNullOrEmpty static method:

[string]::IsNullOrEmpty(...)

Using the last-child selector

If you find yourself frequently wanting CSS3 selectors, you can always use the selectivizr library on your site:

http://selectivizr.com/

It's a JS script that adds support for almost all of the CSS3 selectors to browsers that wouldn't otherwise support them.

Throw it into your <head> tag with an IE conditional:

<!--[if (gte IE 6)&(lte IE 8)]>
  <script src="/js/selectivizr-min.js" type="text/javascript"></script>
<![endif]-->

How to solve privileges issues when restore PostgreSQL Database

AWS RDS users if you are getting this it is because you are not a superuser and according to aws documentation you cannot be one. I have found I have to ignore these errors.

htons() function in socket programing

It has to do with the order in which bytes are stored in memory. The decimal number 5001 is 0x1389 in hexadecimal, so the bytes involved are 0x13 and 0x89. Many devices store numbers in little-endian format, meaning that the least significant byte comes first. So in this particular example it means that in memory the number 5001 will be stored as

0x89 0x13

The htons() function makes sure that numbers are stored in memory in network byte order, which is with the most significant byte first. It will therefore swap the bytes making up the number so that in memory the bytes will be stored in the order

0x13 0x89

On a little-endian machine, the number with the swapped bytes is 0x8913 in hexadecimal, which is 35091 in decimal notation. Note that if you were working on a big-endian machine, the htons() function would not need to do any swapping since the number would already be stored in the right way in memory.

The underlying reason for all this swapping has to do with the network protocols in use, which require the transmitted packets to use network byte order.

How do I use a C# Class Library in a project?

There are necessary steps that are missing in the above answers to work for all levels of devs:

  1. compile your class library project
  2. the dll file will be available in the bin folder
  3. in another project, right click ProjectName and select "Add" => "Existing Item"
  4. Browser to the bin folder of the class library project and select the dll file (3 & 4 steps are important if you plan to ship your app to other machines)
  5. as others mentioned, add reference to the dll file you "just" added to your project
  6. as @Adam mentioned, just call the library name from anywhere in your program, you do not need a using statement

HTTP error 403 in Python 3 Web Scraping

Definitely it's blocking because of your use of urllib based on the user agent. This same thing is happening to me with OfferUp. You can create a new class called AppURLopener which overrides the user-agent with Mozilla.

import urllib.request

class AppURLopener(urllib.request.FancyURLopener):
    version = "Mozilla/5.0"

opener = AppURLopener()
response = opener.open('http://httpbin.org/user-agent')

Source

Why should you use strncpy instead of strcpy?

The strncpy() function is the safer one: you have to pass the maximum length the destination buffer can accept. Otherwise it could happen that the source string is not correctly 0 terminated, in which case the strcpy() function could write more characters to destination, corrupting anything which is in the memory after the destination buffer. This is the buffer-overrun problem used in many exploits

Also for POSIX API functions like read() which does not put the terminating 0 in the buffer, but returns the number of bytes read, you will either manually put the 0, or copy it using strncpy().

In your example code, index is actually not an index, but a count - it tells how many characters at most to copy from source to destination. If there is no null byte among the first n bytes of source, the string placed in destination will not be null terminated

How can I get browser to prompt to save password?

I have been struggling with this myself, and I finally was able to track down the issue and what was causing it to fail.

It all stemmed from the fact that my login form was being dynamically injected into the page (using backbone.js). As soon as I embed my login form directly into my index.html file, everything worked like a charm.

I think this is because the browser has to be aware that there is an existing login form, but since mine was being dynamically injected into the page, it didn't know that a "real" login form ever existed.

Converting rows into columns and columns into rows using R

Here is a tidyverse option that might work depending on the data, and some caveats on its usage:

library(tidyverse)

starting_df %>% 
  rownames_to_column() %>% 
  gather(variable, value, -rowname) %>% 
  spread(rowname, value)

rownames_to_column() is necessary if the original dataframe has meaningful row names, otherwise the new column names in the new transposed dataframe will be integers corresponding to the orignal row number. If there are no meaningful row names you can skip rownames_to_column() and replace rowname with the name of the first column in the dataframe, assuming those values are unique and meaningful. Using the tidyr::smiths sample data would be:

smiths %>% 
    gather(variable, value, -subject) %>% 
    spread(subject, value)

Using the example starting_df with the tidyverse approach will throw a warning message about dropping attributes. This is related to converting columns with different attribute types into a single character column. The smiths data will not give that warning because all columns except for subject are doubles.

The earlier answer using as.data.frame(t()) will convert everything to a factor if there are mixed column types unless stringsAsFactors = FALSE is added, whereas the tidyverse option converts everything to a character by default if there are mixed column types.

What are the differences between if, else, and else if?

if (numOptions == 1)
    return "if";
else if (numOptions > 2)
    return "else if";
else 
    return "else";

Specifying row names when reading in a file

If you used read.table() (or one of it's ilk, e.g. read.csv()) then the easy fix is to change the call to:

read.table(file = "foo.txt", row.names = 1, ....)

where .... are the other arguments you needed/used. The row.names argument takes the column number of the data file from which to take the row names. It need not be the first column. See ?read.table for details/info.

If you already have the data in R and can't be bothered to re-read it, or it came from another route, just set the rownames attribute and remove the first variable from the object (assuming obj is your object)

rownames(obj) <- obj[, 1]  ## set rownames
obj <- obj[, -1]           ## remove the first variable

Is true == 1 and false == 0 in JavaScript?

When compare something with Boolean it works like following

Step 1: Convert boolean to Number Number(true) // 1 and Number(false) // 0

Step 2: Compare both sides

boolean == someting 
-> Number(boolean) === someting

If compare 1 and 2 with true you will get the following results

true == 1
-> Number(true) === 1
-> 1 === 1
-> true

And

true == 2
-> Number(true) === 1
-> 1 === 2
-> false

ASP.NET MVC Custom Error Handling Application_Error Global.asax?

I found a solution for ajax issue noted by Lion_cl.

global.asax:

protected void Application_Error()
    {           
        if (HttpContext.Current.Request.IsAjaxRequest())
        {
            HttpContext ctx = HttpContext.Current;
            ctx.Response.Clear();
            RequestContext rc = ((MvcHandler)ctx.CurrentHandler).RequestContext;
            rc.RouteData.Values["action"] = "AjaxGlobalError";

            // TODO: distinguish between 404 and other errors if needed
            rc.RouteData.Values["newActionName"] = "WrongRequest";

            rc.RouteData.Values["controller"] = "ErrorPages";
            IControllerFactory factory = ControllerBuilder.Current.GetControllerFactory();
            IController controller = factory.CreateController(rc, "ErrorPages");
            controller.Execute(rc);
            ctx.Server.ClearError();
        }
    }

ErrorPagesController

public ActionResult AjaxGlobalError(string newActionName)
    {
        return new AjaxRedirectResult(Url.Action(newActionName), this.ControllerContext);
    }

AjaxRedirectResult

public class AjaxRedirectResult : RedirectResult
{
    public AjaxRedirectResult(string url, ControllerContext controllerContext)
        : base(url)
    {
        ExecuteResult(controllerContext);
    }

    public override void ExecuteResult(ControllerContext context)
    {
        if (context.RequestContext.HttpContext.Request.IsAjaxRequest())
        {
            JavaScriptResult result = new JavaScriptResult()
            {
                Script = "try{history.pushState(null,null,window.location.href);}catch(err){}window.location.replace('" + UrlHelper.GenerateContentUrl(this.Url, context.HttpContext) + "');"
            };

            result.ExecuteResult(context);
        }
        else
        {
            base.ExecuteResult(context);
        }
    }
}

AjaxRequestExtension

public static class AjaxRequestExtension
{
    public static bool IsAjaxRequest(this HttpRequest request)
    {
        return (request.Headers["X-Requested-With"] != null && request.Headers["X-Requested-With"] == "XMLHttpRequest");
    }
}

How do I check if a string contains a specific word?

I think that a good idea is to use mb_stpos:

$haystack = 'How are you?';
$needle = 'are';

if (mb_strpos($haystack, $needle) !== false) {

    echo 'true';
}

Because this solution is case sensitive and safe for all Unicode characters.


But you can also do it like this (sauch response was not yet):

if (count(explode($needle, $haystack)) > 1) {

    echo 'true';
}

This solution is also case sensitive and safe for Unicode characters.

In addition you do not use the negation in the expression, which increases the readability of the code.


Here is other solution using function:

function isContainsStr($haystack, $needle) {

    return count(explode($needle, $haystack)) > 1;
}

if (isContainsStr($haystack, $needle)) {

    echo 'true';
}

HTTPS connections over proxy servers

If it's still of interest, here is an answer to a similar question: Convert HTTP Proxy to HTTPS Proxy in Twisted

To answer the second part of the question:

If yes, what kind of proxy server allows this?

Out of the box, most proxy servers will be configured to allow HTTPS connections only to port 443, so https URIs with custom ports wouldn't work. This is generally configurable, depending on the proxy server. Squid and TinyProxy support this, for example.

Using LINQ to remove elements from a List<T>

Well, it would be easier to exclude them in the first place:

authorsList = authorsList.Where(x => x.FirstName != "Bob").ToList();

However, that would just change the value of authorsList instead of removing the authors from the previous collection. Alternatively, you can use RemoveAll:

authorsList.RemoveAll(x => x.FirstName == "Bob");

If you really need to do it based on another collection, I'd use a HashSet, RemoveAll and Contains:

var setToRemove = new HashSet<Author>(authors);
authorsList.RemoveAll(x => setToRemove.Contains(x));

for each loop in groovy

This one worked for me:

def list = [1,2,3,4]
for(item in list){
    println item
}

Source: Wikia.

Setting network adapter metric priority in Windows 7

I had the same problem on Windows 7 64-bit Pro. I adjusted network adapters binding using Control panel but nothing changed. Also metrics where showing that Win should use Ethernet adapter as primary, but it didn't.

Then a tried to uninstall Ethernet adapter driver and then install it again (without restart) and then I checked metrics for sure.

After this, Windows started prioritize Ethernet adapter.

How to add text inside the doughnut chart using Chart.js?

@Cmyker, great solution for chart.js v2

One little enhancement: It makes sense to check for the appropriate canvas id, see the modified snippet below. Otherwise the text (i.e. 75%) is also rendered in middle of other chart types within the page.

  Chart.pluginService.register({
    beforeDraw: function(chart) {
      if (chart.canvas.id === 'doghnutChart') {
        let width = chart.chart.width,
            height = chart.chart.outerRadius * 2,
            ctx = chart.chart.ctx;

        rewardImg.width = 40;
        rewardImg.height = 40;
        let imageX = Math.round((width - rewardImg.width) / 2),
            imageY = (height - rewardImg.height ) / 2;

        ctx.drawImage(rewardImg, imageX, imageY, 40, 40);
        ctx.save();
      }
    }
  });

Since a legend (see: http://www.chartjs.org/docs/latest/configuration/legend.html) magnifies the chart height, the value for height should be obtained by the radius.

What are the advantages and disadvantages of recursion?

Recursion gets a bad rep, I'm always surprised by the number of developers that wont even touch recursion because someone told them it was evil incarnate.

I've learned through trial and error that when done properly recursion can be one of the fastest ways to iterate over something, it is not a steadfast rule and each language/ compiler/ engine has it's own quirks so mileage will vary.

In javascript I can reliably speed up almost any iterative process by introducing recursion with the added benefit of reducing side effects and making the code more clear concise and reusable. Also pro tip its possible to get around the stack overflow issue (and no you dont disable the warning).

My personal Pros & Cons:

Pros:

- Reduces side effects.
- Makes code more concise and easier to reason about.
- Reduces system resource usage and performs better than the traditional for loop.

Cons:

- Can lead to stack overflow.
- More complicated to setup than a traditional for loop.

Mileage will vary depending on language/ complier/ engine.

How to insert a text at the beginning of a file?

echo -n "text to insert " ;tac filename.txt| tac > newfilename.txt

The first tac pipes the file backwards (last line first) so the "text to insert" appears last. The 2nd tac wraps it once again so the inserted line is at the beginning and the original file is in its original order.

What is the path for the startup folder in windows 2008 server

SHGetKnownFolderPath:

Retrieves the full path of a known folder identified by the folder's KNOWNFOLDERID.

And, FOLDERID_CommonStartup:

Default Path %ALLUSERSPROFILE%\Microsoft\Windows\Start Menu\Programs\StartUp

There are also managed equivalents, but you haven't told us what you're programming in.

Div not expanding even with content inside

You didn't typed the closingtag from the div with id="infohold.

Passing Multiple route params in Angular2

Two Methods for Passing Multiple route params in Angular

Method-1

In app.module.ts

Set path as component2.

imports: [
 RouterModule.forRoot(
 [ {path: 'component2/:id1/:id2', component: MyComp2}])
]

Call router to naviagte to MyComp2 with multiple params id1 and id2.

export class MyComp1 {
onClick(){
    this._router.navigate( ['component2', "id1","id2"]);
 }
}

Method-2

In app.module.ts

Set path as component2.

imports: [
 RouterModule.forRoot(
 [ {path: 'component2', component: MyComp2}])
]

Call router to naviagte to MyComp2 with multiple params id1 and id2.

export class MyComp1 {
onClick(){
    this._router.navigate( ['component2', {id1: "id1 Value", id2: 
    "id2  Value"}]);
 }
}

How to "scan" a website (or page) for info, and bring it into my program?

JSoup solution is great, but if you need to extract just something really simple it may be easier to use regex or String.indexOf

As others have already mentioned the process is called scraping

Getting error "No such module" using Xcode, but the framework is there

Ok, how the same problem was resolved for me was to set the derived data location relative to the workspace directory rather than keeping it default. Go to preferences in xcode. Go to locations tab in preferences and set Derived data to Relative. Hope it helps.

Jupyter Notebook not saving: '_xsrf' argument missing from post

The easiest way I found is this:

https://github.com/nteract/hydrogen/issues/922#issuecomment-405456346

Just open another (non-running, existing) notebook on the same kernel, and the issue is magically gone; you can again save the notebooks that were previously showing the _xsrf error.

If you have already closed the Jupyter home page, you can find a link to it on the terminal from which Jupyter was started.

How to determine the screen width in terms of dp or dip at runtime in Android?

Try this:

Display display   = getWindowManager().getDefaultDisplay();
Point displaySize = new Point();
display.getSize(displaySize);
int width  = displaySize.x;
int height = displaySize.y;

How to round a floating point number up to a certain decimal place?

If you round 8.8333333333339 to 2 decimals, the correct answer is 8.83, not 8.84. The reason you got 8.83000000001 is because 8.83 is a number that cannot be correctly reprecented in binary, and it gives you the closest one. If you want to print it without all the zeros, do as VGE says:

print "%.2f" % 8.833333333339   #(Replace number with the variable?)

Converting xml to string using C#

There's a much simpler way to convert your XmlDocument to a string; use the OuterXml property. The OuterXml property returns a string version of the xml.

public string GetXMLAsString(XmlDocument myxml)
{
    return myxml.OuterXml;
}

endsWith in JavaScript

@chakrit's accepted answer is a solid way to do it yourself. If, however, you're looking for a packaged solution, I recommend taking a look at underscore.string, as @mlunoe pointed out. Using underscore.string, the code would be:

function endsWithHash(str) {
  return _.str.endsWith(str, '#');
}

Can you do a For Each Row loop using MySQL?

Not a for each exactly, but you can do nested SQL

SELECT 
    distinct a.ID, 
    a.col2, 
    (SELECT 
        SUM(b.size) 
    FROM 
        tableb b 
    WHERE 
        b.id = a.col3)
FROM
    tablea a

How do I download/extract font from chrome developers tools?

If you are on a unixoid operating system and want to extract just a single file you can try the following. The structure of the chrome://cache pages is URL, parsed HTTP header, hex dump of the HTTP header and then hex dump of the payload.

To extract a file copy all payload lines from a Chrome cache page to the clipboard (starting at the second 00000000: ... line), paste them into a text editor and save them as a plain text file (e.g. file.txt). If the payload is a gzipped WOFF file use xxd -r file.txt > file.woff.gz to convert it back to a binary file and gunzip file.woff.gz for decompression.

You can then use woff2otf to convert WOFF files to the OTF format or woff2 to convert WOFF 2.0 files to the TTF format. For batch processing this workflow should obviously be scripted.

How to compile a c++ program in Linux?

For simple test project, g++ or make standalone are good options as already answered:

g++ -o hi hi.cpp

or

make hi

For real projects, however, the usage of a project manager is required. At the time I write this answer, the most used and open-source is cmake (an alternative could be QT qmake ).

Following is a simple CMake example:

Make sure you installed cmake on your linux distribution apt-get install cmake or yum install cmake.

Create a file CMakeLists.txt (the name is important) together with your source hi.cpp

project("hi")

add_executable( hi hi.cpp )

Then compile and run as:

cmake .
make
./hi

This allows the project to scale easily with libraries, sources, and much more. It also makes most IDEs to understand the project properly (Most IDEs accept CMake natively, like kdevelop, qtCreator, etc..)

Example of CMake integration with Qt-Creator

You could also generate Visual-Studio or XCode projects from CMake, in case you decide to port the software to other platforms in the future.

cmake -G Xcode . #will generate `hi.xcodeproj` you can load on macOS

How to parse JSON data with jQuery / JavaScript?

Try following code, it works in my project:

//start ajax request
$.ajax({
    url: "data.json",
    //force to handle it as text
    dataType: "text",
    success: function(data) {

        //data downloaded so we call parseJSON function 
        //and pass downloaded data
        var json = $.parseJSON(data);
        //now json variable contains data in json format
        //let's display a few items
        for (var i=0;i<json.length;++i)
        {
            $('#results').append('<div class="name">'+json[i].name+'</>');
        }
    }
});

How can I know if a process is running?

Process.GetProcesses() is the way to go. But you may need to use one or more different criteria to find your process, depending on how it is running (i.e. as a service or a normal app, whether or not it has a titlebar).

Select All distinct values in a column using LINQ

Interestingly enough I tried both of these in LinqPad and the variant using group from Dmitry Gribkov by appears to be quicker. (also the final distinct is not required as the result is already distinct.

My (somewhat simple) code was:

public class Pair 
{ 
    public int id {get;set;}
    public string Arb {get;set;}
}

void Main()
{

    var theList = new List<Pair>();
    var randomiser = new Random();
    for (int count = 1; count < 10000; count++)
    {
        theList.Add(new Pair 
        {
            id = randomiser.Next(1, 50),
            Arb = "not used"
        });
    }

    var timer = new Stopwatch();
    timer.Start();
    var distinct = theList.GroupBy(c => c.id).Select(p => p.First().id);
    timer.Stop();
    Debug.WriteLine(timer.Elapsed);

    timer.Start();
    var otherDistinct = theList.Select(p => p.id).Distinct();
    timer.Stop();
    Debug.WriteLine(timer.Elapsed);
}

Print debugging info from stored procedure in MySQL

One workaround is just to use select without any other clauses.

http://lists.mysql.com/mysql/197901

React Native: JAVA_HOME is not set and no 'java' command could be found in your PATH

Windows 10:

Android Studio -> File -> Other Settings -> Default Project Structure... -> JDK location:

copy string shown, such as:

C:\Program Files\Android\Android Studio\jre

In file locator directory window, right-click on "This PC" ->

Properties -> Advanced System Settings -> Environment Variables... -> System Variables

click on the New... button under System Variables, then type and paste respectively:

.......Variable name: JAVA_HOME

.......Variable value: C:\Program Files\Android\Android Studio\jre

and hit OK buttons to close out.

Some installations may require JRE_HOME to be set as well, the same way.

To check, open a NEW black console window, then type echo %JAVA_HOME% . You should get back the full path you typed into the system variable. Windows 10 seems to support spaces in the filename paths for system variables very well, and does not seem to need ~tilde eliding.

How to do select from where x is equal to multiple values?

You can try using parentheses around the OR expressions to make sure your query is interpreted correctly, or more concisely, use IN:

SELECT ads.*, location.county 
FROM ads
LEFT JOIN location ON location.county = ads.county_id
WHERE ads.published = 1 
AND ads.type = 13
AND ads.county_id IN (2,5,7,9)

I can't find my git.exe file in my Github folder

The path for the latest version of Git is changed, In my laptop, I found it in

C:\Users\Anum Sheraz\AppData\Local\Programs\Git\bin\git.exe

This resolved my issue of path. Hope that helps to someone :)

MySQL table is marked as crashed and last (automatic?) repair failed

I got myisamchk: error: myisam_sort_buffer_size is too small as error.

The solution

myisamchk -r -v mysql/<DB_NAME>/<TABLE_NAME> --sort_buffer_size=2G

How do I make WRAP_CONTENT work on a RecyclerView

From Android Support Library 23.2.1 update, all WRAP_CONTENT should work correctly.

Please update version of a library in gradle file OR to further :

compile 'com.android.support:recyclerview-v7:23.2.1'

solved some issue like Fixed bugs related to various measure-spec methods

Check http://developer.android.com/tools/support-library/features.html#v7-recyclerview

you can check Support Library revision history

UnexpectedRollbackException: Transaction rolled back because it has been marked as rollback-only

This is the normal behavior and the reason is that your sqlCommandHandlerService.persist method needs a TX when being executed (because it is marked with @Transactional annotation). But when it is called inside processNextRegistrationMessage, because there is a TX available, the container doesn't create a new one and uses existing TX. So if any exception occurs in sqlCommandHandlerService.persist method, it causes TX to be set to rollBackOnly (even if you catch the exception in the caller and ignore it).

To overcome this you can use propagation levels for transactions. Have a look at this to find out which propagation best suits your requirements.

Update; Read this!

Well after a colleague came to me with a couple of questions about a similar situation, I feel this needs a bit of clarification.
Although propagations solve such issues, you should be VERY careful about using them and do not use them unless you ABSOLUTELY understand what they mean and how they work. You may end up persisting some data and rolling back some others where you don't expect them to work that way and things can go horribly wrong.


EDIT Link to current version of the documentation

Tooltips for cells in HTML table (no Javascript)

An evolution of what BioData41 added...

Place what follows in CSS style

     <style>

        .CellWithComment{position:relative;}

        .CellComment
        {
            visibility: hidden;
            width: auto;
            position:absolute; 
            z-index:100;
            text-align: Left;
            opacity: 0.4;
            transition: opacity 2s;
            border-radius: 6px;
            background-color: #555;
            padding:3px;
            top:-30px; 
            left:0px;
        }   
        .CellWithComment:hover span.CellComment {visibility: visible;opacity: 1;}
</style>

Then, use it like this:

        <table>
            <tr>
                <th class="CellWithComment">Category<span class="CellComment">"Ciaooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo"</span></th>
                <th class="CellWithComment">Code<span class="CellComment">"Ciaooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo"</span></th>
                <th>Opened</th>
                <th>Event</th>
                <th>Severity</th>           
                <th>Id</th>
                <th>Component Name</th>
            </tr>
            <tr>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
            </tr>
            <tr>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
                <td>Table cell</td>
            </tr>
        </table>

jQuery get html of container including the container itself

var x = $($('div').html($('#container').clone())).html();

Take a screenshot via a Python script on Linux

You can use this

import os
os.system("import -window root screen_shot.png")

C# cannot convert method to non delegate type

To execute a method you need to add parentheses, even if the method does not take arguments.

So it should be:

string t = obj.getTitle();

Compare two folders which has many files inside contents

Diff command in Unix is used to find the differences between files(all types). Since directory is also a type of file, the differences between two directories can easily be figure out by using diff commands. For more option use man diff on your unix box.

 -b              Ignores trailing blanks  (spaces  and  tabs)
                 and   treats  other  strings  of  blanks  as
                 equivalent.

 -i              Ignores the case of  letters.  For  example,
                 `A' will compare equal to `a'.
 -t              Expands <TAB> characters  in  output  lines.
                 Normal or -c output adds character(s) to the
                 front of each line that may adversely affect
                 the indentation of the original source lines
                 and  make  the  output  lines  difficult  to
                 interpret.  This  option  will  preserve the
                 original source's indentation.

 -w              Ignores all blanks (<SPACE> and <TAB>  char-
                 acters)  and  treats  all  other  strings of
                 blanks   as   equivalent.    For    example,
                 `if ( a == b )'   will   compare   equal  to
                 `if(a==b)'.

and there are many more.

Vue.js img src concatenate variable and text

If it helps, I am using the following to get a gravatar image:

<img
        :src="`https://www.gravatar.com/avatar/${this.gravatarHash(email)}?s=${size}&d=${this.defaultAvatar(email)}`"
        class="rounded-circle"
        :width="size"
    />

How to fix "The ConnectionString property has not been initialized"

You get this error when a datasource attempts to bind to data but cannot because it cannot find the connection string. In my experience, this is not usually due to an error in the web.config (though I am not 100% sure of this).

If you are programmatically assigning a datasource (such as a SqlDataSource) or creating a query (i.e. using a SqlConnection/SqlCommand combination), make sure you assigned it a ConnectionString.

var connection = new SqlConnection(ConfigurationManager.ConnectionStrings[nameOfString].ConnectionString);

If you are hooking up a databound element to a datasource (i.e. a GridView or ComboBox to a SqlDataSource), make sure the datasource is assigned to one of your connection strings.

Post your code (for the databound element and the web.config to be safe) and we can take a look at it.

EDIT: I think the problem is that you are trying to get the Connection String from the AppSettings area, and programmatically that is not where it exists. Try replacing that with ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString (if ConnectionString is the name of your connection string.)

How do I translate an ISO 8601 datetime string into a Python datetime object?

Arrow looks promising for this:

>>> import arrow
>>> arrow.get('2014-11-13T14:53:18.694072+00:00').datetime
datetime.datetime(2014, 11, 13, 14, 53, 18, 694072, tzinfo=tzoffset(None, 0))

Arrow is a Python library that provides a sensible, intelligent way of creating, manipulating, formatting and converting dates and times. Arrow is simple, lightweight and heavily inspired by moment.js and requests.

Using global variables between files?

Your 2nd attempt will work perfectly, and is actually a really good way to handle variable names that you want to have available globally. But you have a name error in the last line. Here is how it should be:

# ../myproject/main.py

# Import globfile    
import globfile

# Save myList into globfile
globfile.myList = []

# Import subfile
import subfile

# Do something
subfile.stuff()
print(globfile.myList[0])

See the last line? myList is an attr of globfile, not subfile. This will work as you want.

Mike

How do I tell if a regular file does not exist in Bash?

You can also group multiple commands in the one liner

[ -f "filename" ] || ( echo test1 && echo test2 && echo test3 )

or

[ -f "filename" ] || { echo test1 && echo test2 && echo test3 ;}

If filename doesn't exit, the output will be

test1
test2
test3

Note: ( ... ) runs in a subshell, { ... ;} runs in the same shell. The curly bracket notation works in bash only.

MySQL Great Circle Distance (Haversine formula)

I have had to work this out in some detail, so I'll share my result. This uses a zip table with latitude and longitude tables. It doesn't depend on Google Maps; rather you can adapt it to any table containing lat/long.

SELECT zip, primary_city, 
       latitude, longitude, distance_in_mi
  FROM (
SELECT zip, primary_city, latitude, longitude,r,
       (3963.17 * ACOS(COS(RADIANS(latpoint)) 
                 * COS(RADIANS(latitude)) 
                 * COS(RADIANS(longpoint) - RADIANS(longitude)) 
                 + SIN(RADIANS(latpoint)) 
                 * SIN(RADIANS(latitude)))) AS distance_in_mi
 FROM zip
 JOIN (
        SELECT  42.81  AS latpoint,  -70.81 AS longpoint, 50.0 AS r
   ) AS p 
 WHERE latitude  
  BETWEEN latpoint  - (r / 69) 
      AND latpoint  + (r / 69)
   AND longitude 
  BETWEEN longpoint - (r / (69 * COS(RADIANS(latpoint))))
      AND longpoint + (r / (69 * COS(RADIANS(latpoint))))
  ) d
 WHERE distance_in_mi <= r
 ORDER BY distance_in_mi
 LIMIT 30

Look at this line in the middle of that query:

    SELECT  42.81  AS latpoint,  -70.81 AS longpoint, 50.0 AS r

This searches for the 30 nearest entries in the zip table within 50.0 miles of the lat/long point 42.81/-70.81 . When you build this into an app, that's where you put your own point and search radius.

If you want to work in kilometers rather than miles, change 69 to 111.045 and change 3963.17 to 6378.10 in the query.

Here's a detailed writeup. I hope it helps somebody. http://www.plumislandmedia.net/mysql/haversine-mysql-nearest-loc/

How to get file URL using Storage facade in laravel 5?

If you need absolute URL of the file, use below code:

$file_path = \Storage::url($filename);
$url = asset($file_path);
// Output: http://example.com/storage/filename.jpg

Regex to get NUMBER only from String

\d+

\d represents any digit, + for one or more. If you want to catch negative numbers as well you can use -?\d+.

Note that as a string, it should be represented in C# as "\\d+", or @"\d+"

Shell script to check if file exists

One approach:

(
  shopt -s nullglob
  files=(/home/edward/bank1/fiche/Test*)
  if [[ "${#files[@]}" -gt 0 ]] ; then
    echo found one
  else
    echo found none
  fi
)

Explanation:

  • shopt -s nullglob will cause /home/edward/bank1/fiche/Test* to expand to nothing if no file matches that pattern. (Without it, it will be left intact.)
  • ( ... ) sets up a subshell, preventing shopt -s nullglob from "escaping".
  • files=(/home/edward/bank1/fiche/Test*) puts the file-list in an array named files. (Note that this is within the subshell only; files will not be accessible after the subshell exits.)
  • "${#files[@]}" is the number of elements in this array.

Edited to address subsequent question ("What if i also need to check that these files have data in them and are not zero byte files"):

For this version, we need to use -s (as you did in your question), which also tests for the file's existence, so there's no point using shopt -s nullglob anymore: if no file matches the pattern, then -s on the pattern will be false. So, we can write:

(
  found_nonempty=''
  for file in /home/edward/bank1/fiche/Test* ; do
    if [[ -s "$file" ]] ; then
      found_nonempty=1
    fi
  done
  if [[ "$found_nonempty" ]] ; then
    echo found one
  else
    echo found none
  fi
)

(Here the ( ... ) is to prevent file and found_file from "escaping".)

How can I see if a Perl hash already has a certain key?

I guess that this code should answer your question:

use strict;
use warnings;

my @keys = qw/one two three two/;
my %hash;
for my $key (@keys)
{
    $hash{$key}++;
}

for my $key (keys %hash)
{
   print "$key: ", $hash{$key}, "\n";
}

Output:

three: 1
one: 1
two: 2

The iteration can be simplified to:

$hash{$_}++ for (@keys);

(See $_ in perlvar.) And you can even write something like this:

$hash{$_}++ or print "Found new value: $_.\n" for (@keys);

Which reports each key the first time it’s found.

How to get a reference to an iframe's window object inside iframe's onload handler created from parent window

You're declaring everything in the parent page. So the references to window and document are to the parent page's. If you want to do stuff to the iframe's, use iframe || iframe.contentWindow to access its window, and iframe.contentDocument || iframe.contentWindow.document to access its document.

There's a word for what's happening, possibly "lexical scope": What is lexical scope?

The only context of a scope is this. And in your example, the owner of the method is doc, which is the iframe's document. Other than that, anything that's accessed in this function that uses known objects are the parent's (if not declared in the function). It would be a different story if the function were declared in a different place, but it's declared in the parent page.

This is how I would write it:

(function () {
  var dom, win, doc, where, iframe;

  iframe = document.createElement('iframe');
  iframe.src = "javascript:false";

  where = document.getElementsByTagName('script')[0];
  where.parentNode.insertBefore(iframe, where);

  win = iframe.contentWindow || iframe;
  doc = iframe.contentDocument || iframe.contentWindow.document;

  doc.open();
  doc._l = (function (w, d) {
    return function () {
      w.vanishing_global = new Date().getTime();

      var js = d.createElement("script");
      js.src = 'test-vanishing-global.js?' + w.vanishing_global;

      w.name = "foobar";
      d.foobar = "foobar:" + Math.random();
      d.foobar = "barfoo:" + Math.random();
      d.body.appendChild(js);
    };
  })(win, doc);
  doc.write('<body onload="document._l();"></body>');
  doc.close();
})();

The aliasing of win and doc as w and d aren't necessary, it just might make it less confusing because of the misunderstanding of scopes. This way, they are parameters and you have to reference them to access the iframe's stuff. If you want to access the parent's, you still use window and document.

I'm not sure what the implications are of adding methods to a document (doc in this case), but it might make more sense to set the _l method on win. That way, things can be run without a prefix...such as <body onload="_l();"></body>

How to remove an app with active device admin enabled on Android?

Enter vault password and inside vault right top corner options icon is there. Press on it. In that ->settings->vault admin rites to be unselected. Work done. U can uninstall app now.

TypeError: Can't convert 'int' object to str implicitly

You cannot concatenate a string with an int. You would need to convert your int to a string using the str function, or use formatting to format your output.

Change: -

print("Ok. Your balance is now at " + balanceAfterStrength + " skill points.")

to: -

print("Ok. Your balance is now at {} skill points.".format(balanceAfterStrength))

or: -

print("Ok. Your balance is now at " + str(balanceAfterStrength) + " skill points.")

or as per the comment, use , to pass different strings to your print function, rather than concatenating using +: -

print("Ok. Your balance is now at ", balanceAfterStrength, " skill points.")

How can I use regex to get all the characters after a specific character, e.g. comma (",")

.+,(.+)

Explanation:

.+,

will search for everything before the comma, including the comma.

(.+) 

will search for everything after the comma, and depending on your regex environment,

\1

is the reference for the first parentheses captured group that you need, in this example, everything after the comma.

How different is Objective-C from C++?

Obj-C has much more dynamic capabilities in the language itself, whereas C++ is more focused on compile-time capabilities with some dynamic capabilities.

In, C++ parametric polymorphism is checked at compile-time, whereas in Obj-C, parametric polymorphism is achieved through dynamic dispatch and is not checked at compile-time.

Obj-C is very dynamic in nature. You can add methods to a class during run-time. Also, it has introspection at run-time to look at classes. In C++, the definition of class can't change, and all introspection must be done at compile-time. Although, the dynamic nature of Obj-C could be achieved in C++ using a map of functions(or something like that), it is still more verbose than in Obj-C.

In C++, there is a lot more checks that can be done at compile time. For example, using a variant type(like a union) the compiler can enforce that all cases are written or handled. So you don't forget about handling the edge cases of a problem. However, all these checks come at a price when compiling. Obj-C is much faster at compiling than C++.

How to reduce the image file size using PIL

The main image manager in PIL is PIL's Image module.

from PIL import Image
import math

foo = Image.open("path\\to\\image.jpg")
x, y = foo.size
x2, y2 = math.floor(x-50), math.floor(y-20)
foo = foo.resize((x2,y2),Image.ANTIALIAS)
foo.save("path\\to\\save\\image_scaled.jpg",quality=95)

You can add optimize=True to the arguments of you want to decrease the size even more, but optimize only works for JPEG's and PNG's. For other image extensions, you could decrease the quality of the new saved image. You could change the size of the new image by just deleting a bit of code and defining the image size and you can only figure out how to do this if you look at the code carefully. I defined this size:

x, y = foo.size
x2, y2 = math.floor(x-50), math.floor(y-20)

just to show you what is (almost) normally done with horizontal images. For vertical images you might do:

x, y = foo.size
x2, y2 = math.floor(x-20), math.floor(y-50)

. Remember, you can still delete that bit of code and define a new size.

usr/bin/ld: cannot find -l<nameOfTheLibrary>

During compilation with g++ via make define LIBRARY_PATH if it may not be appropriate to change the Makefile with the -Loption. I had put my extra library in /opt/lib so I did:

$ export LIBRARY_PATH=/opt/lib/

and then ran make for successful compilation and linking.

To run the program with a shared library define:

$ export LD_LIBRARY_PATH=/opt/lib/

before executing the program.

JSON Naming Convention (snake_case, camelCase or PascalCase)

There is no SINGLE standard, but I have seen 3 styles you mention ("Pascal/Microsoft", "Java" (camelCase) and "C" (underscores, snake_case)) -- as well as at least one more, kebab-case like longer-name).

It mostly seems to depend on what background developers of the service in question had; those with c/c++ background (or languages that adopt similar naming, which includes many scripting languages, ruby etc) often choose underscore variant; and rest similarly (Java vs .NET). Jackson library that was mentioned, for example, assumes Java bean naming convention (camelCase)

UPDATE: my definition of "standard" is a SINGLE convention. So while one could claim "yes, there are many standards", to me there are multiple Naming Conventions, none of which is "The" standard overall. One of them could be considered the standard for specific platform, but given that JSON is used for interoperability between platforms that may or may not make much sense.

How to get the type of a variable in MATLAB?

Another related function is whos. It will list all sorts of information (dimensions, byte size, type) for the variables in a given workspace.

>> a = [0 0 7];
>> whos a
  Name      Size            Bytes  Class     Attributes

  a         1x3                24  double              

>> b = 'James Bond';
>> whos b
  Name      Size            Bytes  Class    Attributes

  b         1x10               20  char 

Cut Corners using CSS

You can use clip-path, as Stewartside and Sviatoslav Oleksiv mentioned. To make things easy, I created a sass mixin:

@mixin cut-corners ($left-top, $right-top: 0px, $right-bottom: 0px, $left-bottom: 0px) {
  clip-path: polygon($left-top 0%, calc(100% - #{$right-top}) 0%, 100% $right-top, 100% calc(100% - #{$right-bottom}), calc(100% - #{$right-bottom}) 100%, $left-bottom 100%, 0% calc(100% - #{$left-bottom}), 0% $left-top);
}

.cut-corners {
  @include cut-corners(10px, 0, 25px, 50px);
}

Why is "npm install" really slow?

I was having the same problem, i am on the nodejs version: 8.9.4 and npm version: 5.6.0. I tried a lot solutions online, including the ones on this post, none worked for me, then i found about yarn package manager which solved the problem for me, so if all fails, i think "yarn" is worth checking out.

EDIT:

It seems npm has problems when it is outdated, updating it has helped me as well.

How to re-render flatlist?

If we want the FlatList to know the data change both prop and state,we can construct an object referencing both prop and state and refresh the flatlist.

const hasPropOrStateChange = { propKeyToWatch: this.props, ...this.state};
<FlatList data={...} extraData={this.hasPropOrStateChange} .../>

Docs: https://facebook.github.io/react-native/docs/flatlist#extradata

Can I use jQuery with Node.js?

Not that I know of. The DOM is a client side thing (jQuery doesn't parse the HTML, but the DOM).

Here are some current Node.js projects:

https://github.com/ry/node/wiki (https://github.com/nodejs/node)

And SimonW's djangode is pretty damn cool...

How to calculate difference in hours (decimal) between two dates in SQL Server?

Declare @date1 datetime
Declare @date2 datetime

Set @date1 = '11/20/2009 11:00:00 AM'
Set @date2 = '11/20/2009 12:00:00 PM'

Select Cast(DateDiff(hh, @date1, @date2) as decimal(3,2)) as HoursApart

Result = 1.00

How do I declare a namespace in JavaScript?

The Module pattern was originally defined as a way to provide both private and public encapsulation for classes in conventional software engineering.

When working with the Module pattern, we may find it useful to define a simple template that we use for getting started with it. Here's one that covers name-spacing, public and private variables.

In JavaScript, the Module pattern is used to further emulate the concept of classes in such a way that we're able to include both public/private methods and variables inside a single object, thus shielding particular parts from the global scope. What this results in is a reduction in the likelihood of our function names conflicting with other functions defined in additional scripts on the page.

var myNamespace = (function () {

  var myPrivateVar, myPrivateMethod;

  // A private counter variable
  myPrivateVar = 0;

  // A private function which logs any arguments
  myPrivateMethod = function( foo ) {
      console.log( foo );
  };

  return {

    // A public variable
    myPublicVar: "foo",

    // A public function utilizing privates
    myPublicFunction: function( bar ) {

      // Increment our private counter
      myPrivateVar++;

      // Call our private method using bar
      myPrivateMethod( bar );

    }
  };

})();

Advantages

why is the Module pattern a good choice? For starters, it's a lot cleaner for developers coming from an object-oriented background than the idea of true encapsulation, at least from a JavaScript perspective.

Secondly, it supports private data - so, in the Module pattern, public parts of our code are able to touch the private parts, however the outside world is unable to touch the class's private parts.

Disadvantages

The disadvantages of the Module pattern are that as we access both public and private members differently, when we wish to change visibility, we actually have to make changes to each place the member was used.

We also can't access private members in methods that are added to the object at a later point. That said, in many cases the Module pattern is still quite useful and when used correctly, certainly has the potential to improve the structure of our application.

The Revealing Module Pattern

Now that we're a little more familiar with the module pattern, let’s take a look at a slightly improved version - Christian Heilmann’s Revealing Module pattern.

The Revealing Module pattern came about as Heilmann was frustrated with the fact that he had to repeat the name of the main object when we wanted to call one public method from another or access public variables.He also disliked the Module pattern’s requirement for having to switch to object literal notation for the things he wished to make public.

The result of his efforts was an updated pattern where we would simply define all of our functions and variables in the private scope and return an anonymous object with pointers to the private functionality we wished to reveal as public.

An example of how to use the Revealing Module pattern can be found below

var myRevealingModule = (function () {

        var privateVar = "Ben Cherry",
            publicVar = "Hey there!";

        function privateFunction() {
            console.log( "Name:" + privateVar );
        }

        function publicSetName( strName ) {
            privateVar = strName;
        }

        function publicGetName() {
            privateFunction();
        }


        // Reveal public pointers to
        // private functions and properties

        return {
            setName: publicSetName,
            greeting: publicVar,
            getName: publicGetName
        };

    })();

myRevealingModule.setName( "Paul Kinlan" );

Advantages

This pattern allows the syntax of our scripts to be more consistent. It also makes it more clear at the end of the module which of our functions and variables may be accessed publicly which eases readability.

Disadvantages

A disadvantage of this pattern is that if a private function refers to a public function, that public function can't be overridden if a patch is necessary. This is because the private function will continue to refer to the private implementation and the pattern doesn't apply to public members, only to functions.

Public object members which refer to private variables are also subject to the no-patch rule notes above.

What is the .idea folder?

There is no problem in deleting this. It's not only the WebStorm IDE creating this file, but also PhpStorm and all other of JetBrains' IDEs.

It is safe to delete it but if your project is from GitLab or GitHub then you will see a warning.

Windows 8.1 gets Error 720 on connect VPN

Since I can't find a complete or clear answer on this issue, and since it's the second time that I use this post to fix my problems, I post my solution:

why 720? 720 is the error code for connection attempt fail, because your computer and the remote computer could not agree on PPP control protocol, I don't know exactly why it happens, but I think that is all about registry permission for installers and multiple miniport driver install made by vpn installers that are not properly programmed for win 8.1.

Solution:

  1. check write permissions on registers

    a. download a Process Monitor http://technet.microsoft.com/en-us//sysinternals/bb896645.aspx and run it

    b. Use registry as target and set the filters to check witch registers aren't writable for netsh: "Process Name is 'netsh.exe'" and "result is 'ACCESS DENIED'", then get a command prompt with admin permissions and type netsh int ipv4 reset reset.log

    c. for each registry key logged by the process monitor as not accessible, go to registers using regedit anche change these permissions to "complete access"

    d. run the following command netsh int ipv6 reset reset.log and repeat step c)

  2. unistall all not-working miniports

    a. go to device managers (windows+x -> device manager)

    b. for each not-working miniport (the ones with yellow mark): update driver -> show non-compatible driver -> select another driver (eg. generic broadband adapter)

    c. unistall these not working devices

    d. reboot your computer

    e. Repeat steps a) - d) until you will not see any yellow mark on miniports

  3. delete your vpn connection and create a new one.

that worked for me (2 times, one after my first vpn connection on win 8.1, then when I reinstalled a cisco client and tried to use windows vpn again)

references:

http://en.remontka.pro/error-720-windows-8-and-8-1-solved/

https://forums.lenovo.com/t5/Windows-8-and-8-1/SOLVED-WAN-Miniport-2-yellow-exclamation-mark-in-Device-Manager/td-p/1051981

cURL equivalent in Node.js?

Since looks like node-curl is dead, I've forked it, renamed, and modified to be more curl like and to compile under Windows.

node-libcurl

Usage example:

var Curl = require( 'node-libcurl' ).Curl;

var curl = new Curl();

curl.setOpt( Curl.option.URL, 'www.google.com' );
curl.setOpt( 'FOLLOWLOCATION', true );

curl.on( 'end', function( statusCode, body, headers ) {

    console.info( statusCode );
    console.info( '---' );
    console.info( body.length );
    console.info( '---' );
    console.info( headers );
    console.info( '---' );
    console.info( this.getInfo( Curl.info.TOTAL_TIME ) );

    this.close();
});

curl.on( 'error', function( err, curlErrorCode ) {

    console.error( err.message );
    console.error( '---' );
    console.error( curlErrorCode );

    this.close();

});

curl.perform();

Perform is async, and there is no way to use it synchronous currently (and probably will never have).

It's still in alpha, but this is going to change soon, and help is appreciated.

Now it's possible to use Easy handle directly for sync requests, example:

var Easy = require( 'node-libcurl' ).Easy,
    Curl = require( 'node-libcurl' ).Curl,
    url = process.argv[2] || 'http://www.google.com',
    ret, ch;

ch = new Easy();

ch.setOpt( Curl.option.URL, url );

ch.setOpt( Curl.option.HEADERFUNCTION, function( buf, size, nmemb ) {

    console.log( buf );

    return size * nmemb;
});

ch.setOpt( Curl.option.WRITEFUNCTION, function( buf, size, nmemb ) {

    console.log( arguments );

    return size * nmemb;
});

// this call is sync!
ret = ch.perform();

ch.close();

console.log( ret, ret == Curl.code.CURLE_OK, Easy.strError( ret ) );

Also, the project is stable now!

ASP.NET MVC Razor render without encoding

@(new HtmlString(myString))

Replace a string in shell script using a variable

To let your shell expand the variable, you need to use double-quotes like

sed -i "s#12345678#$replace#g" file.txt

This will break if $replace contain special sed characters (#, \). But you can preprocess $replace to quote them:

replace_quoted=$(printf '%s' "$replace" | sed 's/[#\]/\\\0/g')
sed -i "s#12345678#$replace_quoted#g" file.txt

javascript regex - look behind alternative?

Below is a positive lookbehind JavaScript alternative showing how to capture the last name of people with 'Michael' as their first name.

1) Given this text:

const exampleText = "Michael, how are you? - Cool, how is John Williamns and Michael Jordan? I don't know but Michael Johnson is fine. Michael do you still score points with LeBron James, Michael Green Miller and Michael Wood?";

get an array of last names of people named Michael. The result should be: ["Jordan","Johnson","Green","Wood"]

2) Solution:

function getMichaelLastName2(text) {
  return text
    .match(/(?:Michael )([A-Z][a-z]+)/g)
    .map(person => person.slice(person.indexOf(' ')+1));
}

// or even
    .map(person => person.slice(8)); // since we know the length of "Michael "

3) Check solution

console.log(JSON.stringify(    getMichaelLastName(exampleText)    ));
// ["Jordan","Johnson","Green","Wood"]

Demo here: http://codepen.io/PiotrBerebecki/pen/GjwRoo

You can also try it out by running the snippet below.

_x000D_
_x000D_
const inputText = "Michael, how are you? - Cool, how is John Williamns and Michael Jordan? I don't know but Michael Johnson is fine. Michael do you still score points with LeBron James, Michael Green Miller and Michael Wood?";_x000D_
_x000D_
_x000D_
_x000D_
function getMichaelLastName(text) {_x000D_
  return text_x000D_
    .match(/(?:Michael )([A-Z][a-z]+)/g)_x000D_
    .map(person => person.slice(8));_x000D_
}_x000D_
_x000D_
console.log(JSON.stringify(    getMichaelLastName(inputText)    ));
_x000D_
_x000D_
_x000D_

Resolving MSB3247 - Found conflicts between different versions of the same dependent assembly

I found that (at least in Visual Studio 2010) you need to set the output verbosity to at least Detailed to be able to spot the problem.

It might be that my problem was a reference that was previously a GAC reference, but that was no longer the case after my machine's reinstall.

How to convert a string into double and vice versa?

olliej's rounding method is wrong for negative numbers

  • 2.4 rounded is 2 (olliej's method gets this right)
  • -2.4 rounded is -2 (olliej's method returns -1)

Here's an alternative

  int myInt = (int)(myDouble + (myDouble>0 ? 0.5 : -0.5))

You could of course use a rounding function from math.h

Test iOS app on device without apple developer program or jailbreak

It's worth the buck to apply for the Apple developer program. You will be able to use ad-hoc provisioning to distribute your app to testers and test devices. You're allowed to add 100 ad-hoc provisioning devices to your developer program.

jquery getting post action url

Clean and Simple:

$('#signup').submit(function(event) {

      alert(this.action);
});

How to get all count of mongoose model?

As said before, you code will not work the way it is. A solution to that would be using a callback function, but if you think it would carry you to a 'Callback hell', you can search for "Promisses".

A possible solution using a callback function:

//DECLARE  numberofDocs OUT OF FUNCTIONS
     var  numberofDocs;
     userModel.count({}, setNumberofDocuments); //this search all DOcuments in a Collection

if you want to search the number of documents based on a query, you can do this:

 userModel.count({yourQueryGoesHere}, setNumberofDocuments);

setNumberofDocuments is a separeted function :

var setNumberofDocuments = function(err, count){ 
        if(err) return handleError(err);

        numberofDocs = count;

      };

Now you can get the number of Documents anywhere with a getFunction:

     function getNumberofDocs(){
           return numberofDocs;
        }
 var number = getNumberofDocs();

In addition , you use this asynchronous function inside a synchronous one by using a callback, example:

function calculateNumberOfDoc(someParameter, setNumberofDocuments){

       userModel.count({}, setNumberofDocuments); //this search all DOcuments in a Collection

       setNumberofDocuments(true);


} 

Hope it can help others. :)