Programs & Examples On #Viewexpiredexception

An exception type that is commonly thrown by the JavaServer Faces (JSF) framework

javax.faces.application.ViewExpiredException: View could not be restored

Avoid multipart forms in Richfaces:

<h:form enctype="multipart/form-data">
    <a4j:poll id="poll" interval="10000"/>

If you are using Richfaces, i have found that ajax requests inside of multipart forms return a new View ID on each request.

How to debug:

On each ajax request a View ID is returned, that is fine as long as the View ID is always the same. If you get a new View ID on each request, then there is a problem and must be fixed.

Display all post meta keys and meta values of the same post ID in wordpress

$myvals = get_post_meta( get_the_ID());
foreach($myvals as $key=>$val){
  foreach($val as $vals){
    if ($key=='Youtube'){
       echo $vals 

Key = Youtube videos all meta keys for youtube videos and value

HTML tag <a> want to add both href and onclick working

Use jQuery. You need to capture the click event and then go on to the website.

$("#myHref").on('click', function() {_x000D_
  alert("inside onclick");_x000D_
  window.location = "";_x000D_
<script src=""></script>_x000D_
<a href="#" id="myHref">Click me</a>

How to refresh an IFrame using Javascript?


If it in on same domain just :


will work.

Pull request vs Merge request

In my point of view, they mean the same activity but from different perspectives:

Think about that, Alice makes some commits on repository A, which was forked from Bob's repository B.

When Alice wants to "merge" her changes into B, she actually wants Bob to "pull" these changes from A.

Therefore, from Alice's point of view, it is a "merge request", while Bob views it as a "pull request".

Java. Implicit super constructor Employee() is undefined. Must explicitly invoke another constructor

Any constructor for any class as you know creates an object. So, the constructor should contain proper initialization code for its class. But if you have some class which extends another one (lets call it "parent") then constructor for the class cannot contain all the code needed for the initialization by definition (for example, you cannot define private fields of the parent). That's why constructor of the class has to call constructor of its parent. If you do not call it explicitly then the default parent constructor is called (which is without any parameter).

So, in your case, you can either implement default constructor in parent or directly call any constructor in the class.

Android check permission for LocationManager

Use my custome class to check or request permisson

public class Permissons {

        //Request Permisson
        public static void Request_STORAGE(Activity act,int code)

            ActivityCompat.requestPermissions(act, new
        public static void Request_CAMERA(Activity act,int code)
            ActivityCompat.requestPermissions(act, new
        public static void Request_FINE_LOCATION(Activity act,int code)
            ActivityCompat.requestPermissions(act, new
        public static void Request_READ_SMS(Activity act,int code)
            ActivityCompat.requestPermissions(act, new
        public static void Request_READ_CONTACTS(Activity act,int code)
            ActivityCompat.requestPermissions(act, new
        public static void Request_READ_CALENDAR(Activity act,int code)
            ActivityCompat.requestPermissions(act, new
        public static void Request_RECORD_AUDIO(Activity act,int code)
            ActivityCompat.requestPermissions(act, new

        //Check Permisson
        public static boolean Check_STORAGE(Activity act)
            int result = ContextCompat.checkSelfPermission(act,android.Manifest.permission.WRITE_EXTERNAL_STORAGE);
            return result == PackageManager.PERMISSION_GRANTED;
        public static boolean Check_CAMERA(Activity act)
            int result = ContextCompat.checkSelfPermission(act, Manifest.permission.CAMERA);
            return result == PackageManager.PERMISSION_GRANTED;
        public static boolean Check_FINE_LOCATION(Activity act)
            int result = ContextCompat.checkSelfPermission(act, Manifest.permission.ACCESS_FINE_LOCATION);
            return result == PackageManager.PERMISSION_GRANTED;
        public static boolean Check_READ_SMS(Activity act)
            int result = ContextCompat.checkSelfPermission(act, Manifest.permission.READ_SMS);
            return result == PackageManager.PERMISSION_GRANTED;
        public static boolean Check_READ_CONTACTS(Activity act)
            int result = ContextCompat.checkSelfPermission(act, Manifest.permission.READ_CONTACTS);
            return result == PackageManager.PERMISSION_GRANTED;
        public static boolean Check_READ_CALENDAR(Activity act)
            int result = ContextCompat.checkSelfPermission(act, Manifest.permission.READ_CALENDAR);
            return result == PackageManager.PERMISSION_GRANTED;
        public static boolean Check_RECORD_AUDIO(Activity act)
            int result = ContextCompat.checkSelfPermission(act, Manifest.permission.RECORD_AUDIO);
            return result == PackageManager.PERMISSION_GRANTED;


   //if not permisson granted so request permisson with request code

How to update an object in a List<> in C#

Can also try.

 _lstProductDetail.Where(S => S.ProductID == "")
        .Select(S => { S.ProductPcs = "Update Value" ; return S; }).ToList();


I got this same error when installing to an actual device. More information and a solution to loading the missing libraries to the device can be found at the following site:


To set this up correctly, there are 2 key files that need to be copied to the system:

These files are located in the any of these google app packs:

These links no longer work, but you can find the files in the android sdk if you have Google Maps API v1

After unzipping any of these files, you want to copy the files to your system, like-ah-so:

adb remount

adb push system/etc/permissions/ /system/etc/permissions

adb push system/framework/ /system/framework

adb reboot

How to use ArgumentCaptor for stubbing?

The line


would do the same as


So, using argumentCaptor.capture() when stubbing has no added value. Using Matchers.any() shows better what really happens and therefor is better for readability. With argumentCaptor.capture(), you can't read what arguments are really matched. And instead of using any(), you can use more specific matchers when you have more information (class of the expected argument), to improve your test.

And another problem: If using argumentCaptor.capture() when stubbing it becomes unclear how many values you should expect to be captured after verification. We want to capture a value during verification, not during stubbing because at that point there is no value to capture yet. So what does the argument captors capture method capture during stubbing? It capture anything because there is nothing to be captured yet. I consider it to be undefined behavior and I don't want to use undefined behavior.

Limit the size of a file upload (html input element)

Video file example (HTML + Javascript):

function upload_check()
    var upl = document.getElementById("file_id");
    var max = document.getElementById("max_id").value;

    if(upl.files[0].size > max)
       alert("File too big!");
       upl.value = "";
<form action="some_script" method="post" enctype="multipart/form-data">
    <input id="max_id" type="hidden" name="MAX_FILE_SIZE" value="250000000" />
    <input onchange="upload_check()" id="file_id" type="file" name="file_name" accept="video/*" />
    <input type="submit" value="Upload"/>

Jquery UI tooltip does not support html content

Replacing the \n or the escaped <br/> does the trick while keeping the rest of the HTML escaped:

    content: function() {
        var title = $(this).attr("title") || "";
        return $("<a>").text(title).html().replace(/&lt;br *\/?&gt;/, "<br/>");

PHP isset() with multiple parameters

The parameters of isset() should be separated by a comma sign (,) and not a dot sign (.). Your current code concatenates the variables into a single parameter, instead of passing them as separate parameters.

So the original code evaluates the variables as a unified string value:

isset($_POST['search_term'] . $_POST['postcode']) // Incorrect

While the correct form evaluates them separately as variables:

isset($_POST['search_term'], $_POST['postcode']) // Correct

Android - shadow on text?

 <style name="WhiteTextWithShadow" parent="@android:style/TextAppearance">
    <item name="android:shadowDx">1</item>
    <item name="android:shadowDy">1</item>
    <item name="android:shadowRadius">1</item>
    <item name="android:shadowColor">@android:color/black</item>
    <item name="android:textColor">@android:color/white</item>

then use as

            tools:text="Today, May 21"

How do I add a linker or compile flag in a CMake file?

In newer versions of CMake you can set compiler and linker flags for a single target with target_compile_options and target_link_libraries respectively (yes, the latter sets linker options too):

target_compile_options(first-test PRIVATE -fexceptions)

The advantage of this method is that you can control propagation of options to other targets that depend on this one via PUBLIC and PRIVATE.

As of CMake 3.13 you can also use target_link_options to add linker options which makes the intent more clear.

Replace non-ASCII characters with a single space

For you the get the most alike representation of your original string I recommend the unidecode module:

from unidecode import unidecode
def remove_non_ascii(text):
    return unidecode(unicode(text, encoding = "utf-8"))

Then you can use it in a string:


How to force a list to be vertical using html css

I would add this to the LI's CSS

    float: left;
    clear: left;

Is right click a Javascript event?

Easiest way to get right click done is using

 $('classx').on('contextmenu', function (event) {


However this is not cross browser solution, browsers behave differently for this event especially firefox and IE. I would recommend below for a cross browser solution

$('classx').on('mousedown', function (event) {
    var keycode = ( event.keyCode ? event.keyCode : event.which );
    if (keycode === 3) {
       //your right click code goes here      

Converting a PDF to PNG

Try to extract a single page.

$page = 4

gs -sDEVICE=pngalpha -dFirstPage="$page" -dLastPage="$page" -o thumb.png -r144 input.pdf

Open a workbook using FileDialog and manipulate it in Excel VBA

Unless I misunderstand your question, you can just open a file read only. Here is a simply example, without any checks.

To get the file path from the user use this function:

Private Function get_user_specified_filepath() As String
    'or use the other code example here.
    Dim fd As Office.FileDialog
    Set fd = Application.FileDialog(msoFileDialogFilePicker)
    fd.AllowMultiSelect = False
    fd.Title = "Please select the file."
    get_user_specified_filepath = fd.SelectedItems(1)
End Function

Then just open the file read only and assign it to a variable:

dim wb as workbook
set wb = Workbooks.Open(get_user_specified_filepath(), ReadOnly:=True)

How to convert an array into an object using stdClass()

or you can use this thing

$arr = [1,2,3];
$obj = json_decode(json_encode($arr));

Ubuntu - Run command on start-up with "sudo"

Nice answers. You could also set Jobs (i.e., commands) with "Crontab" for more flexibility (which provides different options to run scripts, loggin the outputs, etc.), although it requires more time to be understood and set properly:

Using '@reboot' you can Run a command once, at startup.

Wrapping up: run $ sudo crontab -e -u root

And add a line at the end of the file with your command as follows:

@reboot sudo searchd

error: Error parsing XML: not well-formed (invalid token) ...?

I tried everything on my end and ended up with the following.

I had the first line as:


And I was missing two spaces there, and it should be:

<?xml version="1.0" encoding="utf-8"?>

Before the version and before the encoding there should be a space.

Multiple REPLACE function in Oracle

In case all your source and replacement strings are just one character long, you can simply use the TRANSLATE function:

  SELECT translate('THIS IS UPPERCASE', 'THISUP', 'thisup') 

See the Oracle documentation for details.

Youtube API Limitations

A little bit late, but you can request a higher quote here:

Java: Most efficient method to iterate over all elements in a org.w3c.dom.Document?

I also stumbled over this problem recently. Here is my solution. I wanted to avoid recursion, so I used a while loop.

Because of the adds and removes in arbitrary places on the list, I went with the LinkedList implementation.

/* traverses tree starting with given node */
  private static List<Node> traverse(Node n)
    return traverse(Arrays.asList(n));

  /* traverses tree starting with given nodes */
  private static List<Node> traverse(List<Node> nodes)
    List<Node> open = new LinkedList<Node>(nodes);
    List<Node> visited = new LinkedList<Node>();

    ListIterator<Node> it = open.listIterator();
    while (it.hasNext() || it.hasPrevious())
      Node unvisited;
      if (it.hasNext())
        unvisited =;
        unvisited = it.previous();


      List<Node> children = getChildren(unvisited);
      for (Node child : children)


    return visited;

  private static List<Node> getChildren(Node n)
    List<Node> children = asList(n.getChildNodes());
    Iterator<Node> it = children.iterator();
    while (it.hasNext())
      if ( != Node.ELEMENT_NODE)
    return children;

  private static List<Node> asList(NodeList nodes)
    List<Node> list = new ArrayList<Node>(nodes.getLength());
    for (int i = 0, l = nodes.getLength(); i < l; i++)
    return list;

Mercurial undo last commit

after you have pulled and updated your workspace do a thg and right click on the change set you want to get rid of and then click modify history -> strip, it will remove the change set and you will point to default tip.

ASP.NET Identity's default Password Hasher - How does it work and is it secure?

Here is how the default implementation (ASP.NET Framework or ASP.NET Core) works. It uses a Key Derivation Function with random salt to produce the hash. The salt is included as part of the output of the KDF. Thus, each time you "hash" the same password you will get different hashes. To verify the hash the output is split back to the salt and the rest, and the KDF is run again on the password with the specified salt. If the result matches to the rest of the initial output the hash is verified.


public static string HashPassword(string password)
    byte[] salt;
    byte[] buffer2;
    if (password == null)
        throw new ArgumentNullException("password");
    using (Rfc2898DeriveBytes bytes = new Rfc2898DeriveBytes(password, 0x10, 0x3e8))
        salt = bytes.Salt;
        buffer2 = bytes.GetBytes(0x20);
    byte[] dst = new byte[0x31];
    Buffer.BlockCopy(salt, 0, dst, 1, 0x10);
    Buffer.BlockCopy(buffer2, 0, dst, 0x11, 0x20);
    return Convert.ToBase64String(dst);


public static bool VerifyHashedPassword(string hashedPassword, string password)
    byte[] buffer4;
    if (hashedPassword == null)
        return false;
    if (password == null)
        throw new ArgumentNullException("password");
    byte[] src = Convert.FromBase64String(hashedPassword);
    if ((src.Length != 0x31) || (src[0] != 0))
        return false;
    byte[] dst = new byte[0x10];
    Buffer.BlockCopy(src, 1, dst, 0, 0x10);
    byte[] buffer3 = new byte[0x20];
    Buffer.BlockCopy(src, 0x11, buffer3, 0, 0x20);
    using (Rfc2898DeriveBytes bytes = new Rfc2898DeriveBytes(password, dst, 0x3e8))
        buffer4 = bytes.GetBytes(0x20);
    return ByteArraysEqual(buffer3, buffer4);

SqlException: DB2 SQL error: SQLCODE: -302, SQLSTATE: 22001, SQLERRMC: null

To get the definition of the SQL codes, the easiest way is to use db2 cli!

at the unix or dos command prompt, just type

db2 "? SQL302"

this will give you the required explanation of the particular SQL code that you normally see in the java exception or your db2 sql output :)

hope this helped.

How to check whether a str(variable) is empty or not?

string = "TEST"
  if str(string):
     print "good string"
except NameError:
     print "bad string"

how to concatenate two dictionaries to create a new one in Python?

You can use the update() method to build a new dictionary containing all the items:

dall = {}

Or, in a loop:

dall = {}
for d in [d1, d2, d3]:

How to remove td border with html?

To remove borders between cells, while retaining the border around the table, add the attribute rules=none to the table tag.

There is no way in HTML to achieve the rendering specified in the last figure of the question. There are various tricky workarounds that are based on using some other markup structure.

Instant run in Android Studio 2.0 (how to turn off)

I tried all above but nothing helps, at last i just figured out that under setting >> apps, device still has an entry for uninstalled application as disabled, i just uninstalled from there and it starts working.

:) might be useful for someone

How to bind DataTable to Datagrid

In cs file:

    private DataTable _dataTable;

    public DataTable DataTable
        get { return _dataTable; }
        set { _dataTable = value; }

    private void Window_Loaded(object sender, RoutedEventArgs e)
        this._dataTable = new DataTable("table");


        this._dataTable.Rows.Add("data00", "data01", "data02");
        this._dataTable.Rows.Add("data10", "data11", "data22");
        this._dataTable.Rows.Add("data20", "data21", "data22");

        this.grid1.DataContext = this;


In Xaml file:

<DataGrid x:Name="grid1"
          ItemsSource="{Binding Path=DataTable, Mode=TwoWay}" />

Cannot deserialize the JSON array (e.g. [1,2,3]) into type ' ' because type requires JSON object (e.g. {"name":"value"}) to deserialize correctly

var objResponse1 = 


Multiple types were found that match the controller named 'Home'

Even though you are not using areas, you can still specify in your RouteMap which namespace to use

    new { controller = "Home", action = "Index" },
    new[] { "NameSpace.OfYour.Controllers" }

But it sounds like the actual issue is the way your two apps are set up in IIS

ASP.NET Setting width of DataBound column in GridView

hey recently i figured it out how to set width if your gridview databound with sql dataset.first set these control RowStyle-Wrap="false" HeaderStyle-Wrap="false" and then you can set the column width as much as you like. ex : ItemStyle-Width="150px" HeaderStyle-Width="150px"

Convert Python program to C/C++ code?

I realize that an answer on a quite new solution is missing. If Numpy is used in the code, I would advice to try Pythran:

For the functions I tried, Pythran gives extremely good results. The resulting functions are as fast as well written Fortran code (or only slightly slower) and a little bit faster than the (quite optimized) Cython solution.

The advantage compared to Cython is that you just have to use Pythran on the Python function optimized for Numpy, meaning that you do not have to expand the loops and add types for all variables in the loop. Pythran takes its time to analyse the code so it understands the operations on numpy.ndarray.

It is also a huge advantage compared to Numba or other projects based on just-in-time compilation for which (to my knowledge), you have to expand the loops to be really efficient. And then the code with the loops becomes very very inefficient using only CPython and Numpy...

A drawback of Pythran: no classes! But since only the functions that really need to be optimized have to be compiled, it is not very annoying.

Another point: Pythran supports well (and very easily) OpenMP parallelism. But I don't think mpi4py is supported...

PHP Warning: include_once() Failed opening '' for inclusion (include_path='.;C:\xampp\php\PEAR')

This should work if current file is located in same directory where initcontrols is:

$base_dir = realpath(dirname(__FILE__)  . $ds . '..') . $ds;
$file = "{$base_dir}initcontrols{$ds}header_myworks.php"; 
echo $plHeader;?>   

Java Could not reserve enough space for object heap error

Go to StartControl PanelSystemAdvanced system settingsadvanced(tab)Environment VariablesSystem VariablesNew:

Variable name: _JAVA_OPTIONS
Variable value: -Xmx512M

JSON Stringify changes time of date because of UTC

JavaScript normally convert local timezone to UTC .

date = new Date();

convert UIImage to NSData

- (void) imageConvert
     UIImage *snapshot = self.myImageView.image;
     [self encodeImageToBase64String:snapshot];

call this method for image convert in base 64 
    -(NSString *)encodeImageToBase64String:(UIImage *)image
        return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];

Laravel 5 How to switch from Production mode

What you could also have a look at is the exposed method Application->loadEnvironmentFrom($file)

I needed one application to run on multiple subdomains. So in bootstrap/app.php I added something like:

$envFile = '.env';
// change $envFile conditionally here

PowerShell: Store Entire Text File Contents in Variable

Get-Content grabs data and dumps it into an array, line by line. Assuming there aren't other special requirements than you listed, you could just save your content into a variable?

$file = Get-Content c:\file\whatever.txt

Running just $file will return the full contents. Then you can just do $file.Count (because arrays already have a count method built in) to get the total # of lines.

Hope this helps! I'm not a scripting wiz, but this seemed easier to me than a lot of the stuff above.

How can I enter latitude and longitude in Google Maps?

You don't need to convert to decimal; you can also enter 46 23S, 115 22E. You can add seconds after the minutes, also separated by a space.

Sequelize OR condition object

For Sequelize 4


SELECT * FROM Student WHERE LastName='Doe' 
AND (FirstName = "John" or FirstName = "Jane") AND Age BETWEEN 18 AND 24 

Syntax with Operators

const Op = require('Sequelize').Op;

var r = await to (Student.findAll(
  where: {
    LastName: "Doe",
    FirstName: {
      [Op.or]: ["John", "Jane"]
    Age: {
      // []: 18
      [Op.between]: [18, 24]


  • For better security Sequelize recommends dropping alias operators $ (e.g $and, $or ...)
  • Unless you have {freezeTableName: true} set in the table model then Sequelize will query against the plural form of its name ( Student -> Students )

Split Spark Dataframe string column into multiple columns

pyspark.sql.functions.split() is the right approach here - you simply need to flatten the nested ArrayType column into multiple top-level columns. In this case, where each array only contains 2 items, it's very easy. You simply use Column.getItem() to retrieve each part of the array as a column itself:

split_col = pyspark.sql.functions.split(df['my_str_col'], '-')
df = df.withColumn('NAME1', split_col.getItem(0))
df = df.withColumn('NAME2', split_col.getItem(1))

The result will be:

col1 | my_str_col | NAME1 | NAME2
  18 |  856-yygrm |   856 | yygrm
 201 |  777-psgdg |   777 | psgdg

I am not sure how I would solve this in a general case where the nested arrays were not the same size from Row to Row.

How to count frequency of characters in a string?

*import java.util.ArrayList;
import java.util.Collections;

public class Freq {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String temp="zsaaqaaaaaaaabbbbbcc";
    List<String> temp1= new ArrayList<String> ();
    ArrayList<Integer>freq=new ArrayList<Integer>();
    for(int i=0;i<temp.length()-1;i++)
    Set<String> uniqset=new HashSet<String>(temp1);
    for(String s:uniqset)
        freq.add(Collections.frequency(temp1, s));
        System.out.println(s+" -->>"+Collections.frequency(temp1, s));

       a -->>10
       b -->>5
       c -->>1
       q -->>1
       s -->>1
       z -->>1

Use collections frequency method to count frequency of char*

Are there any naming convention guidelines for REST APIs?

If you authenticate your clients with Oauth2 I think you will need underscore for at least two of your parameter names:

  • client_id
  • client_secret

I have used camelCase in my (not yet published) REST API. While writing the API documentation I have been thinking of changing everything to snake_case so I don't have to explain why the Oauth params are snake_case while other params are not.


How to split a string by spaces in a Windows batch file?

If someone need to split a string with any delimiter and store values in separate variables, here is the script I built,

FOR /F "tokens=1,2 delims=x" %i in ("1920x1080") do (
  set w=%i
  set h=%j
echo %w%
echo %h%

Explanation: 'tokens' defines what elements you need to pass to the body of FOR, with token delimited by character 'x'. So after delimiting, the first and second token are passed to the body. In the body %i refers to first token and %j refers to second token. We can take %k to refer to 3rd token and so on..

Please also type HELP FOR in cmd to get a detailed explanation.

forward declaration of a struct in C?

Try this

#include <stdio.h>

struct context;

struct funcptrs{
  void (*func0)(struct context *ctx);
  void (*func1)(void);

struct context{
    struct funcptrs fps;

void func1 (void) { printf( "1\n" ); }
void func0 (struct context *ctx) { printf( "0\n" ); }

void getContext(struct context *con){
    con->fps.func0 = func0;  
    con->fps.func1 = func1;  

int main(int argc, char *argv[]){
 struct context c;
   c.fps.func0 = func0;
   c.fps.func1 = func1;
   return 0;

ERROR Error: No value accessor for form control with unspecified name attribute on switch

In my case i used directive, but hadn't imported it in my module.ts file. Import fixed it.

Best way to encode text data for XML

System.XML handles the encoding for you, so you don't need a method like this.

Stacking DIVs on top of each other?

If you mean by literally putting one on the top of the other, one on the top (Same X, Y positions, but different Z position), try using the z-index CSS attribute. This should work (untested)

    <div style='z-index: 1'>1</div>
    <div style='z-index: 2'>2</div>
    <div style='z-index: 3'>3</div>
    <div style='z-index: 4'>4</div>

This should show 4 on the top of 3, 3 on the top of 2, and so on. The higher the z-index is, the higher the element is positioned on the z-axis. I hope this helped you :)

How to change PHP version used by composer

I'm assuming Windows if you're using WAMP. Composer likely is just using the PHP set in your path: How to access PHP with the Command Line on Windows?

You should be able to change the path to PHP using the same instructions.

Otherwise, composer is just a PHAR file, you can download the PHAR and execute it using any PHP:

C:\full\path\to\php.exe C:\full\path\to\composer.phar install

Insert data through ajax into mysql database

Try this:

  $(document).on('click','#save',function(e) {
  var data = $("#form-search").serialize();
         data: data,
         type: "post",
         url: "insertmail.php",
         success: function(data){
              alert("Data Save: " + data);

and in insertmail.php:

error_reporting(E_ALL && ~E_NOTICE);

$sql="INSERT INTO newsletter_email(email) VALUES ('$email')";
echo "You have been successfully subscribed.";

Don't use mysql_ it's deprecated.

another method:

Actually if your problem is null value inserted into the database then try this and here no need of ajax.

    error_reporting(E_ALL && ~E_NOTICE);
    $sql="INSERT INTO newsletter_email(email) VALUES ('$email')";
    //echo "You have been successfully subscribed.";
              setcookie("msg","You have been successfully subscribed.",time()+5,"/");
    <?php if(isset($_COOKIE['msg'])){?>
       <span><?php echo $_COOKIE['msg'];setcookie("msg","",time()-5,"/");?></span> 
    <?php }?>
<form id="form-search" method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
    <span><span class="style2">Enter you email here</span>:</span>
    <input name="email" type="email" id="email" required/>
    <input type="submit" value="subscribe" class="submit"/>

The view didn't return an HttpResponse object. It returned None instead

Because the view must return render, not just call it. Change the last line to

return render(request, 'auth_lifecycle/user_profile.html',

How to get the type of T from a member of a generic class or method?

This is how i did it

internal static Type GetElementType(this Type type)
        //use type.GenericTypeArguments if exist 
        if (type.GenericTypeArguments.Any())
         return type.GenericTypeArguments.First();

         return type.GetRuntimeProperty("Item").PropertyType);

Then call it like this

var item = Activator.CreateInstance(iListType.GetElementType());


var item = Activator.CreateInstance(Bar.GetType().GetElementType());

Using Apache httpclient for https

According to the documentation you need to specify the key store:

Protocol authhttps = new Protocol("https",  
      new AuthSSLProtocolSocketFactory(
          new URL("file:my.keystore"), "mypassword",
          new URL("file:my.truststore"), "mypassword"), 443); 

 HttpClient client = new HttpClient();
 client.getHostConfiguration().setHost("localhost", 443, authhttps);

JSON Structure for List of Objects

As others mentioned, Justin's answer was close, but not quite right. I tested this using Visual Studio's "Paste JSON as C# Classes"

    "foos" : [

orderBy multiple fields in Angular

Make sure that the sorting is not to complicated for the end user. I always thought sorting on group and sub group is a little bit complicated to understand. If its a technical end user it might be OK.

How to check if a process is running via a batch script

Another possibility I came up with, inspired by using grep, is:

tasklist /FI "IMAGENAME eq myapp.exe" 2>NUL | find /I /N "myapp.exe">NUL
if "%ERRORLEVEL%"=="0" echo Program is running

It doesn't need to save an extra file, so I prefer this method.

Handling null values in Freemarker

You can use the ?? test operator:

This checks if the attribute of the object is not null:

<#if object.attribute??></#if>

This checks if object or attribute is not null:

<#if (object.attribute)??></#if>

Source: FreeMarker Manual

How do I add an integer value with javascript (jquery) to a value that's returning a string?

Simply, add a plus sign before the text value

var newValue = +currentValue + 1;

How do you print in a Go test using the "testing" package?

In case your using testing.M and associated setup/teardown; -v is valid here as well.

package g 

import (

func TestSomething(t *testing.T) {

func setup() {
    fmt.Println("setting up")

func teardown() {
    fmt.Println("tearing down")

func TestMain(m *testing.M) {
    result := m.Run()
$ go test -v g_test.go 
setting up
=== RUN   TestSomething
    g_test.go:10: later
--- SKIP: TestSomething (0.00s)
tearing down
ok      command-line-arguments  0.002s

Date format Mapping to JSON Jackson

To add characters such as T and Z in your date

@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ss'Z'")
private Date currentTime;


    "currentTime": "2019-12-11T11:40:49Z"

SQL Server: Importing database from .mdf?

Apart from steps mentioned in posted answers by @daniele3004 above, I had to open SSMS as Administrator otherwise it was showing Primary file is read only error.

Go to Start Menu , navigate to SSMS link , right click on the SSMS link , select Run As Administrator. Then perform the above steps.

What does ${} (dollar sign and curly braces) mean in a string in Javascript?

You can also perform Implicit Type Conversions with template literals. Example:

let fruits = ["mango","orange","pineapple","papaya"];

console.log(`My favourite fruits are ${fruits}`);
// My favourite fruits are mango,orange,pineapple,papaya

Cannot deserialize instance of object out of START_ARRAY token in Spring Webservice

I've had a very similar issue using spring-boot-starter-data-redis. To my implementation there was offered a @Bean for RedisTemplate as follows:

public RedisTemplate<String, List<RoutePlantCache>> redisTemplate(RedisConnectionFactory connectionFactory) {
    final RedisTemplate<String, List<RoutePlantCache>> template = new RedisTemplate<>();
    template.setKeySerializer(new StringRedisSerializer());
    template.setValueSerializer(new Jackson2JsonRedisSerializer<>(RoutePlantCache.class));

    // Add some specific configuration here. Key serializers, etc.
    return template;

The fix was to specify an array of RoutePlantCache as following:

template.setValueSerializer(new Jackson2JsonRedisSerializer<>(RoutePlantCache[].class));

Below the exception I had:

com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot deserialize instance of `[...].RoutePlantCache` out of START_ARRAY token
 at [Source: (byte[])"[{ ... },{ ... [truncated 1478 bytes]; line: 1, column: 1]
    at com.fasterxml.jackson.databind.exc.MismatchedInputException.from( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.DeserializationContext.reportInputMismatch( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.DeserializationContext.handleUnexpectedToken( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.DeserializationContext.handleUnexpectedToken( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeFromArray( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose( ~[jackson-databind-2.11.4.jar:2.11.4]
    at com.fasterxml.jackson.databind.ObjectMapper.readValue( ~[jackson-databind-2.11.4.jar:2.11.4]

"CSV file does not exist" for a filename with embedded quotes

Just referring to the filename like

df = pd.read_csv("FBI-CRIME11.csv")

generally only works if the file is in the same directory as the script.

If you are using windows, make sure you specify the path to the file as follows:

PATH = "C:\\Users\\path\\to\\file.csv"

jQuery autocomplete tagging plug-in like StackOverflow's input tags?

Bootstrap: If you are using Bootstrap. This is a really good one: Select2

Also, TokenInput is an interesting one. First, it does not depend on jQuery-UI, second its config is very smooth.

The only issue I had it does not support free-tagging natively. So, I have to return the query-string back to client as a part of response JSON.

As @culithay mentioned in the comment, TokenInput supports a lot of features to customize. And highlight of some feature that the others don't have:

  • tokenLimit: The maximum number of results allowed to be selected by the user. Use null to allow unlimited selections
  • minChars: The minimum number of characters the user must enter before a search is performed.
  • queryParam: The name of the query param which you expect to contain the search term on the server-side

Thanks culithay for the input.

Is it possible to use global variables in Rust?

You can use static variables fairly easily as long as they are thread-local.

The downside is that the object will not be visible to other threads your program might spawn. The upside is that unlike truly global state, it is entirely safe and is not a pain to use - true global state is a massive pain in any language. Here's an example:

extern mod sqlite;

use std::cell::RefCell;

thread_local!(static ODB: RefCell<sqlite::database::Database> = RefCell::new(sqlite::open("test.db"));

fn main() {
    ODB.with(|odb_cell| {
        let odb = odb_cell.borrow_mut();
        // code that uses odb goes here

Here we create a thread-local static variable and then use it in a function. Note that it is static and immutable; this means that the address at which it resides is immutable, but thanks to RefCell the value itself will be mutable.

Unlike regular static, in thread-local!(static ...) you can create pretty much arbitrary objects, including those that require heap allocations for initialization such as Vec, HashMap and others.

If you cannot initialize the value right away, e.g. it depends on user input, you may also have to throw Option in there, in which case accessing it gets a bit unwieldy:

extern mod sqlite;

use std::cell::RefCell;

thread_local!(static ODB: RefCell<Option<sqlite::database::Database>> = RefCell::New(None));

fn main() {
    ODB.with(|odb_cell| {
        // assumes the value has already been initialized, panics otherwise
        let odb = odb_cell.borrow_mut().as_mut().unwrap();
        // code that uses odb goes here

How to remove array element in mongodb?

You can simply use $pull to remove a sub-document. The $pull operator removes from an existing array all instances of a value or values that match a specified condition.

    _id: parentDocumentId
  }, {
    $pull: {
      subDocument: {
        _id: SubDocumentId

This will find your parent document against given ID and then will remove the element from subDocument which matched the given criteria.

Read more about pull here.

How to extract text from a PDF?

As the question is specifically about alternative tools to get data from PDF as XML so you may be interested to take a look at the commercial tool "ByteScout PDF Extractor SDK" that is capable of doing exactly this: extract text from PDF as XML along with the positioning data (x,y) and font information:

Text in the source PDF:

Products | Units | Price 

Output XML:

  <text fontName="Arial" fontSize="11.0" fontStyle="Bold" x="212" y="126" width="47" height="11">Products</text> 
  <text fontName="Arial" fontSize="11.0" fontStyle="Bold" x="428" y="126" width="27" height="11">Units</text> 
  <text fontName="Arial" fontSize="11.0" fontStyle="Bold" x="503" y="126" width="26" height="11">Price</text> 

P.S.: additionally it also breaks the text into a table based structure.

Disclosure: I work for ByteScout

Using "If cell contains" in VBA excel

This will loop through all cells in a given range that you define ("RANGE TO SEARCH") and add dashes at the cell below using the Offset() method. As a best practice in VBA, you should never use the Select method.

Sub AddDashes()

Dim SrchRng As Range, cel As Range

Set SrchRng = Range("RANGE TO SEARCH")

For Each cel In SrchRng
    If InStr(1, cel.Value, "TOTAL") > 0 Then
        cel.Offset(1, 0).Value = "-"
    End If
Next cel

End Sub

Get value from JToken that may not exist (best practices)

You can simply typecast, and it will do the conversion for you, e.g.

var with = (double?) jToken[key] ?? 100;

It will automatically return null if said key is not present in the object, so there's no need to test for it.

How to read from a file or STDIN in Bash?

The echo solution adds new lines whenever IFS breaks the input stream. @fgm's answer can be modified a bit:

cat "${1:-/dev/stdin}" > "${2:-/dev/stdout}"

Get Enum from Description attribute

You can't extend Enum as it's a static class. You can only extend instances of a type. With this in mind, you're going to have to create a static method yourself to do this; the following should work when combined with your existing method GetDescription:

public static class EnumHelper
    public static T GetEnumFromString<T>(string value)
        if (Enum.IsDefined(typeof(T), value))
            return (T)Enum.Parse(typeof(T), value, true);
            string[] enumNames = Enum.GetNames(typeof(T));
            foreach (string enumName in enumNames)
                object e = Enum.Parse(typeof(T), enumName);
                if (value == GetDescription((Enum)e))
                    return (T)e;
        throw new ArgumentException("The value '" + value 
            + "' does not match a valid enum name or description.");

And the usage of it would be something like this:

Animal giantPanda = EnumHelper.GetEnumFromString<Animal>("Giant Panda");

How do I check in JavaScript if a value exists at a certain array index?

You can use Loadsh library to do this more efficiently, like:

if you have an array named "pets", for example:

var pets = ['dog', undefined, 'cat', null];

console.log(_.isEmpty(pets[1])); // true
console.log(_.isEmpty(pets[3])); // true
console.log(_.isEmpty(pets[4])); // false pets, (pet, index) => { console.log(index + ': ' + _.isEmpty(pet) ) });

To check all array values for null or undefined values:

var pets = ['dog', undefined, 'cat', null];_x000D_
console.log(_.isEmpty(pets[1])); // true_x000D_
console.log(_.isEmpty(pets[3])); // true_x000D_
console.log(_.isEmpty(pets[4])); // false_x000D_
_x000D_ pets, (pet, index) => { console.log(index + ': ' + _.isEmpty(pet) ) });
<script src=""></script>

Check more examples in

did you specify the right host or port? error on Kubernetes

I was also getting same below error:

Unable to connect to the server: dial tcp [::1]:8080: connectex: No connection could be made because the target machine actively refused it.

Then I just execute below command and found everything working fine.

PS C:> .\minikube.exe start

Starting local Kubernetes v1.10.0 cluster... Starting VM... Downloading Minikube ISO 150.53 MB / 150.53 MB [============================================] 100.00% 0s Getting VM IP address... Moving files into cluster... Downloading kubeadm v1.10.0 Downloading kubelet v1.10.0 Finished Downloading kubelet v1.10.0 Finished Downloading kubeadm v1.10.0 Setting up certs... Connecting to cluster... Setting up kubeconfig... Starting cluster components... Kubectl is now configured to use the cluster. Loading cached images from config file. PS C:> .\minikube.exe start Starting local Kubernetes v1.10.0 cluster... Starting VM... Getting VM IP address... Moving files into cluster... Setting up certs... Connecting to cluster... Setting up kubeconfig... Starting cluster components... Kubectl is now configured to use the cluster.

Extension mysqli is missing, phpmyadmin doesn't work

Checking the extension_dir is one of the thing you like to check from phpinfo().In my case it was extension_dir = "./" by default which was wrong. Change it to extension_dir = './ext/' or where all your extension dlls are currently residing.

C# equivalent of the IsNull() function in SQL Server

Use the Equals method:

object value2 = null;

CommandError: You must set settings.ALLOWED_HOSTS if DEBUG is False

Just simply comment out the line: ALLOWED_HOSTS = [...]

Powershell Log Off Remote Session

Below script will work well for both active and disconnected sessions as long as user has access to run logoff command remotely. All you have to do is change the servername from "YourServerName" on 4th line.

param (
    $queryResults = $null,
    [string]$UserName = $env:USERNAME,
    [string]$ServerName = "YourServerName"

if (Test-Connection $ServerName -Count 1 -Quiet) {  
    Write-Host "`n`n`n$ServerName is online!" -BackgroundColor Green -ForegroundColor Black

    Write-Host ("`nQuerying Server: `"$ServerName`" for disconnected sessions under UserName: `"" + $UserName.ToUpper() + "`"...") -BackgroundColor Gray -ForegroundColor Black

        query user $UserName /server:$ServerName 2>&1 | foreach {  

            if ($_ -match "Active") {
                Write-Host "Active Sessions"
                $queryResults = ("`n$ServerName," + (($_.trim() -replace ' {2,}', ','))) | ConvertFrom-Csv -Delimiter "," -Header "ServerName","UserName","SessionName","SessionID","CurrentState","IdealTime","LogonTime"

                $queryResults | ft
                Write-Host "Starting logoff procedure..." -BackgroundColor Gray -ForegroundColor Black

                $queryResults | foreach {
                    $Sessionl = $_.SessionID
                    $Serverl = $_.ServerName
                    Write-Host "Logging off"$_.username"from $serverl..." -ForegroundColor black -BackgroundColor Gray
                    sleep 2
                    logoff $Sessionl /server:$Serverl /v


            elseif ($_ -match "Disc") {
                Write-Host "Disconnected Sessions"
                $queryResults = ("`n$ServerName," + (($_.trim() -replace ' {2,}', ','))) |  ConvertFrom-Csv -Delimiter "," -Header "ServerName","UserName","SessionID","CurrentState","IdealTime","LogonTime"

                $queryResults | ft
                Write-Host "Starting logoff procedure..." -BackgroundColor Gray -ForegroundColor Black

                $queryResults | foreach {
                    $Sessionl = $_.SessionID
                    $Serverl = $_.ServerName
                    Write-Host "Logging off"$_.username"from $serverl..."
                    sleep 2
                    logoff $Sessionl /server:$Serverl /v

            elseif ($_ -match "The RPC server is unavailable") {

                Write-Host "Unable to query the $ServerName, check for firewall settings on $ServerName!" -ForegroundColor White -BackgroundColor Red
            elseif ($_ -match "No User exists for") {Write-Host "No user session exists"}

else {

    Write-Host "`n`n`n$ServerName is Offline!" -BackgroundColor red -ForegroundColor white
    Write-Host "Error: Unable to connect to $ServerName!" -BackgroundColor red -ForegroundColor white
    Write-Host "Either the $ServerName is down or check for firewall settings on server $ServerName!" -BackgroundColor Yellow -ForegroundColor black

Read-Host "`n`nScript execution finished, press enter to exit!"

Some sample outputs. For active session: enter image description here

For disconnected sessions: enter image description here

if no sessions found: enter image description here Check out this solution as well to query all AD servers for your username and logoff only disconnected sessions. The script will also tell you if there were error connecting or querying the server.

Powershell to find out disconnected RDP session and log off at the same time

How do I count unique values inside a list

How about:

import pandas as pd
#List with all words

#Code for adding words

#When Input equals blank:

It returns how many unique values are in a list

C multi-line macro: do/while(0) vs scope block

Andrey Tarasevich provides the following explanation:

  1. On Google Groups
  2. On

[Minor changes to formatting made. Parenthetical annotations added in square brackets []].

The whole idea of using 'do/while' version is to make a macro which will expand into a regular statement, not into a compound statement. This is done in order to make the use of function-style macros uniform with the use of ordinary functions in all contexts.

Consider the following code sketch:

if (<condition>)

where foo and bar are ordinary functions. Now imagine that you'd like to replace function foo with a macro of the above nature [named CALL_FUNCS]:

if (<condition>)

Now, if your macro is defined in accordance with the second approach (just { and }) the code will no longer compile, because the 'true' branch of if is now represented by a compound statement. And when you put a ; after this compound statement, you finished the whole if statement, thus orphaning the else branch (hence the compilation error).

One way to correct this problem is to remember not to put ; after macro "invocations":

if (<condition>)

This will compile and work as expected, but this is not uniform. The more elegant solution is to make sure that macro expand into a regular statement, not into a compound one. One way to achieve that is to define the macro as follows:

#define CALL_FUNCS(x) \
do { \
  func1(x); \
  func2(x); \
  func3(x); \
} while (0)

Now this code:

if (<condition>)

will compile without any problems.

However, note the small but important difference between my definition of CALL_FUNCS and the first version in your message. I didn't put a ; after } while (0). Putting a ; at the end of that definition would immediately defeat the entire point of using 'do/while' and make that macro pretty much equivalent to the compound-statement version.

I don't know why the author of the code you quoted in your original message put this ; after while (0). In this form both variants are equivalent. The whole idea behind using 'do/while' version is not to include this final ; into the macro (for the reasons that I explained above).

Define: What is a HashSet?

From application perspective, if one needs only to avoid duplicates then HashSet is what you are looking for since it's Lookup, Insert and Remove complexities are O(1) - constant. What this means it does not matter how many elements HashSet has it will take same amount of time to check if there's such element or not, plus since you are inserting elements at O(1) too it makes it perfect for this sort of thing.

What are the differences and similarities between ffmpeg, libav, and avconv?

Confusing messages

These messages are rather misleading and understandably a source of confusion. Older Ubuntu versions used Libav which is a fork of the FFmpeg project. FFmpeg returned in Ubuntu 15.04 "Vivid Vervet".

The fork was basically a non-amicable result of conflicting personalities and development styles within the FFmpeg community. It is worth noting that the maintainer for Debian/Ubuntu switched from FFmpeg to Libav on his own accord due to being involved with the Libav fork.

The real ffmpeg vs the fake one

For a while both Libav and FFmpeg separately developed their own version of ffmpeg.

Libav then renamed their bizarro ffmpeg to avconv to distance themselves from the FFmpeg project. During the transition period the "not developed anymore" message was displayed to tell users to start using avconv instead of their counterfeit version of ffmpeg. This confused users into thinking that FFmpeg (the project) is dead, which is not true. A bad choice of words, but I can't imagine Libav not expecting such a response by general users.

This message was removed upstream when the fake "ffmpeg" was finally removed from the Libav source, but, depending on your version, it can still show up in Ubuntu because the Libav source Ubuntu uses is from the ffmpeg-to-avconv transition period.

In June 2012, the message was re-worded for the package libav - 4:0.8.3-0ubuntu0.12.04.1. Unfortunately the new "deprecated" message has caused additional user confusion.

Starting with Ubuntu 15.04 "Vivid Vervet", FFmpeg's ffmpeg is back in the repositories again.

libav vs Libav

To further complicate matters, Libav chose a name that was historically used by FFmpeg to refer to its libraries (libavcodec, libavformat, etc). For example the libav-user mailing list, for questions and discussions about using the FFmpeg libraries, is unrelated to the Libav project.

How to tell the difference

If you are using avconv then you are using Libav. If you are using ffmpeg you could be using FFmpeg or Libav. Refer to the first line in the console output to tell the difference: the copyright notice will either mention FFmpeg or Libav.

Secondly, the version numbering schemes differ. Each of the FFmpeg or Libav libraries contains a version.h header which shows a version number. FFmpeg will end in three digits, such as 57.67.100, and Libav will end in one digit such as 57.67.0. You can also view the library version numbers by running ffmpeg or avconv and viewing the console output.

If you want to use the real ffmpeg

Ubuntu 15.04 "Vivid Vervet" or newer

The real ffmpeg is in the repository, so you can install it with:

apt-get install ffmpeg

For older Ubuntu versions

Your options are:

These methods are non-intrusive, reversible, and will not interfere with the system or any repository packages.

Another possible option is to upgrade to Ubuntu 15.04 "Vivid Vervet" or newer and just use ffmpeg from the repository.

Also see

For an interesting blog article on the situation, as well as a discussion about the main technical differences between the projects, see The FFmpeg/Libav situation.

Use a content script to access the page context variables and functions

You can use a utility function I've created for the purpose of running code in the page context and getting back the returned value.

This is done by serializing a function to a string and injecting it to the web page.

The utility is available here on GitHub.

Usage examples -

// Some code that exists only in the page context -
window.someProperty = 'property';
function someFunction(name = 'test') {
    return new Promise(res => setTimeout(()=>res('resolved ' + name), 1200));

// Content script examples -

await runInPageContext(() => someProperty); // returns 'property'

await runInPageContext(() => someFunction()); // returns 'resolved test'

await runInPageContext(async (name) => someFunction(name), 'with name' ); // 'resolved with name'

await runInPageContext(async (...args) => someFunction(...args), 'with spread operator and rest parameters' ); // returns 'resolved with spread operator and rest parameters'

await runInPageContext({
    func: (name) => someFunction(name),
    args: ['with params object'],
    doc: document,
    timeout: 10000
} ); // returns 'resolved with params object'

Oracle 11g SQL to get unique values in one column of a multi-column query

For efficiency's sake you want to only hit the data once, as Harper does. However you don't want to use rank() because it will give you ties and further you want to group by language rather than order by language. From there you want add an order by clause to distinguish between rows, but you don't want to actually sort the data. To achieve this I would use "order by null" E.g.

count(*) over (group by language order by null)

How to avoid page refresh after button click event in

Add OnClientClick="return false;" ,

<asp:button ID="btninsert" runat="server" text="Button" OnClientClick="return false;" />

or in the CodeBehind:

 btninsert.Attributes.Add("onclick", "return false;");

Function vs. Stored Procedure in SQL Server

Basic Difference

Function must return a value but in Stored Procedure it is optional( Procedure can return zero or n values).

Functions can have only input parameters for it whereas Procedures can have input/output parameters .

Function takes one input parameter it is mandatory but Stored Procedure may take o to n input parameters..

Functions can be called from Procedure whereas Procedures cannot be called from Function.

Advance Difference

Procedure allows SELECT as well as DML(INSERT/UPDATE/DELETE) statement in it whereas Function allows only SELECT statement in it.

Procedures can not be utilized in a SELECT statement whereas Function can be embedded in a SELECT statement.

Stored Procedures cannot be used in the SQL statements anywhere in the WHERE/HAVING/SELECT section whereas Function can be.

Functions that return tables can be treated as another rowset. This can be used in JOINs with other tables.

Inline Function can be though of as views that take parameters and can be used in JOINs and other Rowset operations.

Exception can be handled by try-catch block in a Procedure whereas try-catch block cannot be used in a Function.

We can go for Transaction Management in Procedure whereas we can't go in Function.


What is the use of the %n format specifier in C?

%n is C99, works not with VC++.

Safest way to convert float to integer in python?

Combining two of the previous results, we have:


This converts a float to an integer fairly dependably.

Find duplicate records in a table using SQL Server

Try this instead

SELECT MAX(shoppername), COUNT(*) AS cnt
FROM dbo.sales

Read about the CHECKSUM function first, as there can be duplicates.

Bigger Glyphicons

In my case, I had an input-group-btn with a button, and this button was a little bigger than its container. So I just gave font-size:95% for my glyphicon and it was solved.

<div class="input-group">
    <input type="text" class="form-control" id="pesquisarinbox" placeholder="Pesquisar na Caixa de Entrada">
    <div class="input-group-btn">
        <button class="btn btn-default" type="button">
            <span class="glyphicon glyphicon-search" style="font-size:95%;"></span>

When should iteritems() be used instead of items()?

The six library helps with writing code that is compatible with both python 2.5+ and python 3. It has an iteritems method that will work in both python 2 and 3. Example:

import six

d = dict( foo=1, bar=2 )

for k, v in six.iteritems(d):
    print(k, v)

Difference between .on('click') vs .click()

Is there any difference between the following code?

No, there is no functional difference between the two code samples in your question. .click(fn) is a "shortcut method" for .on("click", fn). From the documentation for .on():

There are shorthand methods for some events such as .click() that can be used to attach or trigger event handlers. For a complete list of shorthand methods, see the events category.

Note that .on() differs from .click() in that it has the ability to create delegated event handlers by passing a selector parameter, whereas .click() does not. When .on() is called without a selector parameter, it behaves exactly the same as .click(). If you want event delegation, use .on().

How do I pre-populate a jQuery Datepicker textbox with today's date?

$('.date-pick').datePicker().val(new Date().asString()).trigger('change');


String.equals() with multiple conditions (and one action on result)


  • Use String.equals():

    if (some_string.equals("john") ||
        some_string.equals("mary") ||
  • Use a regular expression:

    if (some_string.matches("john|mary|peter"))
  • Store a list of strings to be matched against in a Collection and search the collection:

    Set<String> names = new HashSet<String>();
    if (names.contains(some_string))

SQL Server: Attach incorrect version 661

SQL Server 2008 databases are version 655. SQL Server 2008 R2 databases are 661. You are trying to attach an 2008 R2 database (v. 661) to an 2008 instance and this is not supported. Once the database has been upgraded to an 2008 R2 version, it cannot be downgraded. You'll have to either upgrade your 2008 SP2 instance to R2, or you have to copy out the data in that database into an 2008 database (eg using the data migration wizard, or something equivalent).

The message is misleading, to say the least, it says 662 because SQL Server 2008 SP2 does support 662 as a database version, this is when 15000 partitions are enabled in the database, see Support for 15000 Partitions.docx. Enabling the support bumps the DB version to 662, disabling it moves it back to 655. But SQL Server 2008 SP2 does not support 661 (the R2 version).

unable to start mongodb local server


/usr/lib/mongodb/mongod.exe --dbpath c:data\db

--dbpath (should be followed by the path of your db)

Html.DropdownListFor selected value not being set

You should forget the class


Use this in your Controller:

var customerTypes = new[] 
    new SelectListItem(){Value = "all", Text= "All"},
    new SelectListItem(){Value = "business", Text= "Business"},
    new SelectListItem(){Value = "private", Text= "Private"},

Select the value:

var selectedCustomerType = customerTypes.FirstOrDefault(d => d.Value == "private");
if (selectedCustomerType != null)
    selectedCustomerType.Selected = true;

Add the list to the ViewData:

ViewBag.CustomerTypes = customerTypes;

Use this in your View:

@Html.DropDownList("SectionType", (SelectListItem[])ViewBag.CustomerTypes)


More information at:

Using union and count(*) together in SQL query

Is your goal...

  1. To count all the instances of "Bob Jones" in both tables (for example)
  2. To count all the instances of "Bob Jones" in Results in one row and all the instances of "Bob Jones" in Archive_Results in a separate row?

Assuming it's #1 you'd want something like...

(SELECT name FROM Results UNION ALL SELECT name FROM Archive_Results)

Clearing a text field on button click

If you want to reset it, then simple use:

<input type="reset" value="Reset" />

But beware, it will not clear out textboxes that have default value. For example, if we have the following textboxes and by default, they have the following values:

<input id="textfield1" type="text" value="sample value 1" />
<input id="textfield2" type="text" value="sample value 2" />

So, to clear it out, compliment it with javascript:

function clearText()  
    document.getElementById('textfield1').value = "";
    document.getElementById('textfield2').value = "";

And attach it to onclick of the reset button:
<input type="reset" value="Reset" onclick="clearText()" />

Using stored procedure output parameters in C#

In your C# code, you are using transaction for the command. Just commit the transaction and after that access your parameter value, you will get the value. Worked for me. :)

How do I remove the space between inline/inline-block elements?


item {
  display: inline-block;
  margin-right: -0.25em;

There is no need to touch the parent element.

Only condition here: the item's font-size must not be defined (must be equal to parent's font-size).

0.25em is the default word-spacing

W3Schools - word-spacing property

How to resize an image to fit in the browser window?

Update 2018-04-11

Here's a Javascript-less, CSS-only solution. The image will dynamically be centered and resized to fit the window.

        * {
            margin: 0;
            padding: 0;
        .imgbox {
            display: grid;
            height: 100%;
        .center-fit {
            max-width: 100%;
            max-height: 100vh;
            margin: auto;
<div class="imgbox">
    <img class="center-fit" src='pic.png'>

The [other, old] solution, using JQuery, sets the height of the image container (body in the example below) so that the max-height property on the image works as expected. The image will also automatically resize when the client window is resized.

<!DOCTYPE html>
        * {
            padding: 0;
            margin: 0;
        .fit { /* set relative picture size */
            max-width: 100%;
            max-height: 100%;
        .center {
            display: block;
            margin: auto;

<img class="center fit" src="pic.jpg" >

<script src=""></script>
<script type="text/javascript" language="JavaScript">
    function set_body_height() { // set body height = window height
    $(document).ready(function() {
        $(window).bind('resize', set_body_height);


Note: User gutierrezalex packaged a very similar solution as a JQuery plugin on this page.

How can I remove the outline around hyperlinks images?

For Internet Explorer 9:

a:active, a:focus { 
 outline: none; 
 ie-dummy: expression(this.hideFocus=true);


Convert JSON String to Pretty Print JSON output using Jackson

If you format the string and return object like RestApiResponse<String>, you'll get unwanted characters like escaping etc: \n, \". Solution is to convert your JSON-string into Jackson JsonNode object and return RestApiResponse<JsonNode>:

ObjectMapper mapper = new ObjectMapper();
JsonNode tree = objectMapper.readTree(jsonString);
RestApiResponse<JsonNode> response = new RestApiResponse<>();
return response;

Why should we NOT use sys.setdefaultencoding("utf-8") in a py script?


The answer is NEVER! (unless you really know what you're doing)

9/10 times the solution can be resolved with a proper understanding of encoding/decoding.

1/10 people have an incorrectly defined locale or environment and need to set:


in their environment to fix console printing problems.

What does it do?

sys.setdefaultencoding("utf-8") (struck through to avoid re-use) changes the default encoding/decoding used whenever Python 2.x needs to convert a Unicode() to a str() (and vice-versa) and the encoding is not given. I.e:


In Python 2.x, the default encoding is set to ASCII and the above examples will fail with:

UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0: ordinal not in range(128)

(My console is configured as UTF-8, so "€" = '\xe2\x82\xac', hence exception on \xe2)


UnicodeEncodeError: 'ascii' codec can't encode character u'\u20ac' in position 0: ordinal not in range(128)

sys.setdefaultencoding("utf-8") will allow these to work for me, but won't necessarily work for people who don't use UTF-8. The default of ASCII ensures that assumptions of encoding are not baked into code


sys.setdefaultencoding("utf-8") also has a side effect of appearing to fix sys.stdout.encoding, used when printing characters to the console. Python uses the user's locale (Linux/OS X/Un*x) or codepage (Windows) to set this. Occasionally, a user's locale is broken and just requires PYTHONIOENCODING to fix the console encoding.


$ export LANG=en_GB.gibberish
$ python
>>> import sys
>>> sys.stdout.encoding
>>> print u"\u20AC"
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\u20ac' in position 0: ordinal not in range(128)
>>> exit()

>>> import sys
>>> sys.stdout.encoding
>>> print u"\u20AC"

What's so bad with sys.setdefaultencoding("utf-8")?

People have been developing against Python 2.x for 16 years on the understanding that the default encoding is ASCII. UnicodeError exception handling methods have been written to handle string to Unicode conversions on strings that are found to contain non-ASCII.


def welcome_message(byte_string):
        return u"%s runs your business" % byte_string
    except UnicodeError:
        return u"%s runs your business" % unicode(byte_string,

print(welcome_message(u"Angstrom (Å®)".encode("latin-1"))

Previous to setting defaultencoding this code would be unable to decode the “Å” in the ascii encoding and then would enter the exception handler to guess the encoding and properly turn it into unicode. Printing: Angstrom (Å®) runs your business. Once you’ve set the defaultencoding to utf-8 the code will find that the byte_string can be interpreted as utf-8 and so it will mangle the data and return this instead: Angstrom (U) runs your business.

Changing what should be a constant will have dramatic effects on modules you depend upon. It's better to just fix the data coming in and out of your code.

Example problem

While the setting of defaultencoding to UTF-8 isn't the root cause in the following example, it shows how problems are masked and how, when the input encoding changes, the code breaks in an unobvious way: UnicodeDecodeError: 'utf8' codec can't decode byte 0x80 in position 3131: invalid start byte

HTML button onclick event

You should all know this is inline scripting and is not a good practice at all...with that said you should definitively use javascript or jQuery for this type of thing:


<!DOCTYPE html> 
    <meta charset="ISO-8859-1"> 
    <title>Online Student Portal</title> 
    <form action="">
         <input type="button" id="myButton" value="Add"/>


var button_my_button = "#myButton";


  //get a reference to the element
  var myBtn = document.getElementById('myButton');

  //add event listener
  myBtn.addEventListener('click', function(event) {

See comments why avoid inline scripting and also why inline scripting is bad

PHP Configuration: It is not safe to rely on the system's timezone settings

Tchalvak, who commented on the original question, hit the nail on the head for me. I've been editing (I use Debian):


...which had the correct timezone for me and was the only .ini file being loaded with date.timezone within it, but I was receiving the above error when I ran a script through Bash. I had no idea that I should have been editing:


as well. (Well, for me it was 'as well', for you it might be different of course, but I'm going to keep my Apache and CLI versions of php.ini synchronised now).

Child with max-height: 100% overflows parent

Your container does not have a height.

Add height: 200px;

to the containers css and the kitty will stay inside.

How to change the Spyder editor background to dark?

I tried the option: Tools > Preferences > Syntax coloring > dark spyder is not working.

You should rather use the path: Tools > Preferences > Syntax coloring > spyder then begin modifications as you want your editor to appear

C#: Looping through lines of multiline string

Sometimes I think we can overcomplicate the solution just to avoid repeating one line of code. This is the reason I landed on this question in the first place.

After thinking about it for a bit I came to the conclusion that the simplest solution is to repeat the ReadLine before and inside the loop.

using (var stringReader = new StringReader(input))
    var line = await stringReader.ReadLineAsync();

    while (line != null)
        // do something
        line = await stringReader.ReadLineAsync();

I realize this might be considered to not follow the DRY principle, but I think it's worth considering given the simplicity.

How do I find the PublicKeyToken for a particular dll?

Using sn.exe utility:

sn -T YourAssembly.dll

or loading the assembly in Reflector.

Insert and set value with max()+1 problems

Correct, you can not modify and select from the same table in the same query. You would have to perform the above in two separate queries.

The best way is to use a transaction but if your not using innodb tables then next best is locking the tables and then performing your queries. So:

Lock tables customers write;

$max = SELECT MAX( customer_id ) FROM customers;

Grab the max id and then perform the insert

INSERT INTO customers( customer_id, firstname, surname )
VALUES ($max+1 , 'jim', 'sock')

unlock tables;

Android Studio doesn't see device

After spending some time I found the problem was to enable USB debugging option to on. Just find in your mobile Settings->Developer Option->USB debugging. Just enable it and it works. It might help someone!

enter image description here

What is the '.well' equivalent class in Bootstrap 4

Looking for a one line option:

    <div class="jumbotron bg-dark"> got a team? </div>

utf-8 special characters not displaying

If all the other answers didn't work for you, try disabling HTTP input encoding translation.

This is a setting related to PHP extension mbstring. This was the problem in my case. This setting was enabled by default in my server.

What exactly is a Context in Java?

A Context represents your environment. It represents the state surrounding where you are in your system.

For example, in web programming in Java, you have a Request, and a Response. These are passed to the service method of a Servlet.

A property of the Servlet is the ServletConfig, and within that is a ServletContext.

The ServletContext is used to tell the servlet about the Container that the Servlet is within.

So, the ServletContext represents the servlets environment within its container.

Similarly, in Java EE, you have EBJContexts that elements (like session beans) can access to work with their containers.

Those are two examples of contexts used in Java today.

Edit --

You mention Android.

Look here:

You can see how this Context gives you all sorts of information about where the Android app is deployed and what's available to it.

How do I create a folder in VB if it doesn't exist?

If(Not System.IO.Directory.Exists(YourPath)) Then
End If

Specifying row names when reading in a file

See ?read.table. Basically, when you use read.table, you specify a number indicating the column:

##Row names in the first column
read.table(filname.txt, row.names=1)

VMWare Player vs VMWare Workstation

Workstation has some features that Player lacks, such as teams (groups of VMs connected by private LAN segments) and multi-level snapshot trees. It's aimed at power users and developers; they even have some hooks for using a debugger on the host to debug code in the VM (including kernel-level stuff). The core technology is the same, though.

Calculate row means on subset of columns

(Another solution using pivot_longer & pivot_wider from latest Tidyr update)

You should try using pivot_longer to get your data from wide to long form Read latest tidyR update on pivot_longer & pivot_wider (


Output here

  ID     mean
  <fct> <dbl>
1 A      3.67
2 B      4.33
3 C      3.33
4 D      4.67
5 E      4.33

Input Type image submit form value?

I've found that image-buttons DO return a response, but you should NOT use a value-option. What I see returned are two version of the name="MYNAME" with .X and .Y endings.

For example:

<input type="image" src="/path-to/stop.png" name="STOP" width="25" height="25" align="top" alt="Stop sign">

This is within your <form> to </form>. If you click the image, what's returned are STOP.X and STOP.Y with numeric values. The existence of either indicates the STOP image-button was clicked. You don't need any special code. Just treat it as another kind of "submit" button that returns a pair of augmented NAMEs.

I've tried this on Safari, Firefox and Chrome. The image wasn't displayed with Safari, but where it was supposed to be located, my cursor turned into a finger-icon, and I could click it.

What does <? php echo ("<pre>"); ..... echo("</pre>"); ?> mean?

The <pre> is used to define pre-formatted text.
The text within <pre> tag is displayed in a fixed-width font and it preserves both spaces and line breaks that are present in the text.
Here I'm printing a JSON FILE without <pre> tag and then with <pre> tag.

Without <pre> tag
With <pre> tag

Installing Tomcat 7 as Service on Windows Server 2008

You can find the solution here!

Install the service named 'Tomcat7'

C:\>Tomcat\bin\service.bat install

There is a 2nd optional parameter that lets you specify the name of the service, as displayed in Windows services.

Install the service named 'MyTomcatService'

C:\>Tomcat\bin\service.bat install MyTomcatService

Filter rows which contain a certain string


It is possible to use str_detect of the stringr package included in the tidyverse package. str_detect returns True or False as to whether the specified vector contains some specific string. It is possible to filter using this boolean value. See Introduction to stringr for details about stringr package.

# - Attaching packages -------------------- tidyverse 1.2.1 -
# ? ggplot2 2.2.1     ? purrr   0.2.4
# ? tibble  1.4.2     ? dplyr   0.7.4
# ? tidyr   0.7.2     ? stringr 1.2.0
# ? readr   1.1.1     ? forcats 0.3.0
# - Conflicts --------------------- tidyverse_conflicts() -
# ? dplyr::filter() masks stats::filter()
# ? dplyr::lag()    masks stats::lag()

mtcars$type <- rownames(mtcars)
mtcars %>%
  filter(str_detect(type, 'Toyota|Mazda'))
# mpg cyl  disp  hp drat    wt  qsec vs am gear carb           type
# 1 21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4      Mazda RX4
# 2 21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4  Mazda RX4 Wag
# 3 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1 Toyota Corolla
# 4 21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1  Toyota Corona

The good things about Stringr

We should use rather stringr::str_detect() than base::grepl(). This is because there are the following reasons.

  • The functions provided by the stringr package start with the prefix str_, which makes the code easier to read.
  • The first argument of the functions of stringr package is always the data.frame (or value), then comes the parameters.(Thank you Paolo)
object <- "stringr"
# The functions with the same prefix `str_`.
# The first argument is an object.
stringr::str_count(object) # -> 7
stringr::str_sub(object, 1, 3) # -> "str"
stringr::str_detect(object, "str") # -> TRUE
stringr::str_replace(object, "str", "") # -> "ingr"
# The function names without common points.
# The position of the argument of the object also does not match.
base::nchar(object) # -> 7
base::substr(object, 1, 3) # -> "str"
base::grepl("str", object) # -> TRUE
base::sub("str", "", object) # -> "ingr"


The results of the benchmark test are as follows. For large dataframe, str_detect is faster.


# The data. Data expo 09. ASA Statistics Computing and Graphics 
df <- read_csv("Downloads/2008.csv")
# [1] 7009728      29

  "str_detect" = {df %>% filter(str_detect(Dest, 'MCO|BWI'))},
  "grepl" = {df %>% filter(grepl('MCO|BWI', Dest))},
  replications = 10,
  columns = c("test", "replications", "elapsed", "relative", "user.self", "sys.self"))
# test replications elapsed relative user.self sys.self
# 2      grepl           10  16.480    1.513    16.195    0.248
# 1 str_detect           10  10.891    1.000     9.594    1.281

Why won't bundler install JSON gem?

If the recommended answer didn't help because you are already using a newer version of bundler. Try the solution that worked for me.

Delete everything inside your vendor folder. Add a line to your gemfile

gem 'json', '1.8.0'

Then run - bundle update json.

It seems to be an issue with 1.8.1 so going back to 1.8.0 did the trick for me.

Convert javascript object or array to json for ajax data

I'm not entirely sure but I think you are probably surprised at how arrays are serialized in JSON. Let's isolate the problem. Consider following code:

var display = Array();
display[0] = "none";
display[1] = "block";
display[2] = "none";

console.log( JSON.stringify(display) );

This will print:


This is how JSON actually serializes array. However what you want to see is something like:


To get this format you want to serialize object, not array. So let's rewrite above code like this:

var display2 = {};
display2["0"] = "none";
display2["1"] = "block";
display2["2"] = "none";

console.log( JSON.stringify(display2) );

This will print in the format you want.

You can play around with this here:,console

C free(): invalid pointer

From where did you get the idea that you need to free(token) and free(tk)? You don't. strsep() doesn't allocate memory, it only returns pointers inside the original string. Of course, those are not pointers allocated by malloc() (or similar), so free()ing them is undefined behavior. You only need to free(s) when you are done with the entire string.

Also note that you don't need dynamic memory allocation at all in your example. You can avoid strdup() and free() altogether by simply writing char *s = p;.

Inheriting constructors

You have to explicitly define the constructor in B and explicitly call the constructor for the parent.

B(int x) : A(x) { }


B() : A(5) { }

Create a Dropdown List for MVC3 using Entity Framework (.edmx Model) & Razor Views && Insert A Database Record to Multiple Tables

Don't pass db models directly to your views. You're lucky enough to be using MVC, so encapsulate using view models.

Create a view model class like this:

public class EmployeeAddViewModel
    public Employee employee { get; set; }
    public Dictionary<int, string> staffTypes { get; set; }
    // really? a 1-to-many for genders
    public Dictionary<int, string> genderTypes { get; set; }

    public EmployeeAddViewModel() { }
    public EmployeeAddViewModel(int id)
        employee = someEntityContext.Employees
            .Where(e => e.ID == id).SingleOrDefault();

        // instantiate your dictionaries

        foreach(var staffType in someEntityContext.StaffTypes)
            staffTypes.Add(staffType.ID, staffType.Type);

        // repeat similar loop for gender types


public ActionResult Add()
    return View(new EmployeeAddViewModel());

public ActionResult Add(EmployeeAddViewModel vm)
        return View("Index"); // or wherever you go after successful add

    return View(vm);

Then, finally in your view (which you can use Visual Studio to scaffold it first), change the inherited type to ShadowVenue.Models.EmployeeAddViewModel. Also, where the drop down lists go, use:

@Html.DropDownListFor(model => model.employee.staffTypeID,
    new SelectList(model.staffTypes, "ID", "Type"))

and similarly for the gender dropdown

@Html.DropDownListFor(model => model.employee.genderID,
    new SelectList(model.genderTypes, "ID", "Gender"))

Update per comments

For gender, you could also do this if you can be without the genderTypes in the above suggested view model (though, on second thought, maybe I'd generate this server side in the view model as IEnumerable). So, in place of new SelectList... below, you would use your IEnumerable.

@Html.DropDownListFor(model => model.employee.genderID,
    new SelectList(new SelectList()
        new { ID = 1, Gender = "Male" },
        new { ID = 2, Gender = "Female" }
    }, "ID", "Gender"))

Finally, another option is a Lookup table. Basically, you keep key-value pairs associated with a Lookup type. One example of a type may be gender, while another may be State, etc. I like to structure mine like this:

ID | LookupType | LookupKey | LookupValue | LookupDescription | Active
1  | Gender     | 1         | Male        | male gender       | 1
2  | State      | 50        | Hawaii      | 50th state        | 1
3  | Gender     | 2         | Female      | female gender     | 1
4  | State      | 49        | Alaska      | 49th state        | 1
5  | OrderType  | 1         | Web         | online order      | 1

I like to use these tables when a set of data doesn't change very often, but still needs to be enumerated from time to time.

Hope this helps!

Get protocol, domain, and port from URL

first get the current address

var url = window.location.href

Then just parse that string

var arr = url.split("/");

your url is:

var result = arr[0] + "//" + arr[2]

Hope this helps

Android camera android.hardware.Camera deprecated

Answers provided here as which camera api to use are wrong. Or better to say they are insufficient.

Some phones (for example Samsung Galaxy S6) could be above api level 21 but still may not support Camera2 api.

CameraCharacteristics mCameraCharacteristics = mCameraManager.getCameraCharacteristics(mCameraId);
Integer level = mCameraCharacteristics.get(CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL);
if (level == null || level == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY) {
    return false;

CameraManager class in Camera2Api has a method to read camera characteristics. You should check if hardware wise device is supporting Camera2 Api or not.

But there are more issues to handle if you really want to make it work for a serious application: Like, auto-flash option may not work for some devices or battery level of the phone might create a RuntimeException on Camera or phone could return an invalid camera id and etc.

So best approach is to have a fallback mechanism as for some reason Camera2 fails to start you can try Camera1 and if this fails as well you can make a call to Android to open default Camera for you.

On delete cascade with doctrine2

There are two kinds of cascades in Doctrine:

1) ORM level - uses cascade={"remove"} in the association - this is a calculation that is done in the UnitOfWork and does not affect the database structure. When you remove an object, the UnitOfWork will iterate over all objects in the association and remove them.

2) Database level - uses onDelete="CASCADE" on the association's joinColumn - this will add On Delete Cascade to the foreign key column in the database:

@ORM\JoinColumn(name="father_id", referencedColumnName="id", onDelete="CASCADE")

I also want to point out that the way you have your cascade={"remove"} right now, if you delete a Child object, this cascade will remove the Parent object. Clearly not what you want.


I don't know why

cfg_name_unique NOT LIKE '%categories%' 

still returns those two values, but maybe exclude them explicit:

    FROM developer_configurations_cms

    WHERE developer_configurations_cms.cat_id = '1'
    AND developer_configurations_cms.cfg_variables LIKE '%parent_id=2%'
    AND developer_configurations_cms.cfg_name_unique NOT LIKE '%categories%'
    AND developer_configurations_cms.cfg_name_unique NOT IN ('categories_posts', 'categories_news')

How can I programmatically check whether a keyboard is present in iOS app?

Create a UIKeyboardListener when you know the keyboard is not visible, for example by calling [UIKeyboardListener shared] from applicationDidFinishLaunching.

@implementation UIKeyboardListener

+ (UIKeyboardListener) shared {
    static UIKeyboardListener sListener;    
    if ( nil == sListener ) sListener = [[UIKeyboardListener alloc] init];

    return sListener;

-(id) init {
    self = [super init];

    if ( self ) {
        NSNotificationCenter        *center = [NSNotificationCenter defaultCenter];
        [center addObserver:self selector:@selector(noticeShowKeyboard:) name:UIKeyboardDidShowNotification object:nil];
        [center addObserver:self selector:@selector(noticeHideKeyboard:) name:UIKeyboardWillHideNotification object:nil];

    return self;

-(void) noticeShowKeyboard:(NSNotification *)inNotification {
    _visible = true;

-(void) noticeHideKeyboard:(NSNotification *)inNotification {
    _visible = false;

-(BOOL) isVisible {
    return _visible;


View stored procedure/function definition in MySQL

Perfect, try it:


Nginx serves .php files as downloads, instead of executing them

for a record, I found that my php-fpm was not running and I fixed it with service php7.2-fpm stop

Get yesterday's date using Date

You can do following:

private Date getMeYesterday(){
     return new Date(System.currentTimeMillis()-24*60*60*1000);

Note: if you want further backward date multiply number of day with 24*60*60*1000 for example:

private Date getPreviousWeekDate(){
     return new Date(System.currentTimeMillis()-7*24*60*60*1000);

Similarly, you can get future date by adding the value to System.currentTimeMillis(), for example:

private Date getMeTomorrow(){
     return new Date(System.currentTimeMillis()+24*60*60*1000);

Add a CSS border on hover without moving the element

Try this it might solve your problem.



.jobs .item:hover {
    background: #e1e1e1;
    border-top: 1px solid #d0d0d0;


<div class="jobs">
    <div class="item">
        content goes here

See fiddle for output:

How can I check whether Google Maps is fully loaded?

If you're using web components, then they have this as an example:

map.addEventListener('google-map-ready', function(e) {
   alert('Map loaded!');

Is Python interpreted, or compiled, or both?

The answer depends on what implementation of python is being used. If you are using lets say CPython (The Standard implementation of python) or Jython (Targeted for integration with java programming language)it is first translated into bytecode, and depending on the implementation of python you are using, this bycode is directed to the corresponding virtual machine for interpretation. PVM (Python Virtual Machine) for CPython and JVM (Java Virtual Machine) for Jython.

But lets say you are using PyPy which is another standard CPython implementation. It would use a Just-In-Time Compiler.

How can I compile LaTeX in UTF8?

You needed to iconv your source.

That said, the TEX-based compiler invoked by latex doesn't really support variable-length encodings; it needs big libraries that tell it that certain bytes go together. Xelatex is Unicode-aware and works much better.

Is there a way to access an iteration-counter in Java's for-each loop?

The easiest solution is to just run your own counter thus:

int i = 0;
for (String s : stringArray) {
    doSomethingWith(s, i);

The reason for this is because there's no actual guarantee that items in a collection (which that variant of for iterates over) even have an index, or even have a defined order (some collections may change the order when you add or remove elements).

See for example, the following code:

import java.util.*;

public class TestApp {
  public static void AddAndDump(AbstractSet<String> set, String str) {
    System.out.println("Adding [" + str + "]");
    int i = 0;
    for(String s : set) {
        System.out.println("   " + i + ": " + s);

  public static void main(String[] args) {
    AbstractSet<String> coll = new HashSet<String>();
    AddAndDump(coll, "Hello");
    AddAndDump(coll, "My");
    AddAndDump(coll, "Name");
    AddAndDump(coll, "Is");
    AddAndDump(coll, "Pax");

When you run that, you can see something like:

Adding [Hello]
   0: Hello
Adding [My]
   0: Hello
   1: My
Adding [Name]
   0: Hello
   1: My
   2: Name
Adding [Is]
   0: Hello
   1: Is
   2: My
   3: Name
Adding [Pax]
   0: Hello
   1: Pax
   2: Is
   3: My
   4: Name

indicating that, rightly so, order is not considered a salient feature of a set.

There are other ways to do it without a manual counter but it's a fair bit of work for dubious benefit.

"Data too long for column" - why?

In my case this error occurred due to entering data a wrong type for example: if it is a long type column, i tried to enter in string type. so please check your data that you are entering and type are same or not

How do I set the default value for an optional argument in Javascript?

ES6 Update - ES6 (ES2015 specification) allows for default parameters

The following will work just fine in an ES6 (ES015) environment...

function(nodeBox, str="hai")
  // ...

How to set up devices for VS Code for a Flutter emulator

You do not need to create a virtual device using android studio. You can use your android device running on android 8.0 or higher. All you have to do is to activate developer settings, then enable USB DEBUGGING in the developer settings. Your device will show at the bottom right side of the VS Code. Without enabling the USB debugging, the device may not show.enter image description here

Get Locale Short Date Format using javascript

If your question about <input type="date"> field, here is script for getting filed value="" attribute:

(new Date()).toISOString().split('T')[0]

You can use the Intl object (ecma-402) to get data-date-pattern="":

(new Intl.DateTimeFormat()).resolved.pattern // "M/d/y" for "en-US" in Google Chrome

And finnaly, to format date in current l10n, data-date="":

(new Intl.DateTimeFormat()).format(new Date());


How to use a typescript enum value in an Angular2 ngSwitch statement

My component used an object myClassObject of type MyClass, which itself was using MyEnum. This lead to the same issue described above. Solved it by doing:

export enum MyEnum {
export class MyClass {
    myEnum: typeof MyEnum;
    myEnumField: MyEnum;
    someOtherField: string;

and then using this in the template as

<div [ngSwitch]="myClassObject.myEnumField">
  <div *ngSwitchCase="myClassObject.myEnum.Option1">
    Do something for Option1
  <div *ngSwitchCase="myClassObject.myEnum.Option2">
    Do something for Option2
  <div *ngSwitchCase="myClassObject.myEnum.Option3">
    Do something for Opiton3

Computing cross-correlation function?

If you are looking for a rapid, normalized cross correlation in either one or two dimensions I would recommend the openCV library (see The cross-correlation code maintained by this group is the fastest you will find, and it will be normalized (results between -1 and 1).

While this is a C++ library the code is maintained with CMake and has python bindings so that access to the cross correlation functions is convenient. OpenCV also plays nicely with numpy. If I wanted to compute a 2-D cross-correlation starting from numpy arrays I could do it as follows.

import numpy
import cv

#Create a random template and place it in a larger image
templateNp = numpy.random.random( (100,100) )
image = numpy.random.random( (400,400) )
image[:100, :100] = templateNp

#create a numpy array for storing result
resultNp = numpy.zeros( (301, 301) )

#convert from numpy format to openCV format
templateCv = cv.fromarray(numpy.float32(template))
imageCv = cv.fromarray(numpy.float32(image))
resultCv =  cv.fromarray(numpy.float32(resultNp))

#perform cross correlation
cv.MatchTemplate(templateCv, imageCv, resultCv, cv.CV_TM_CCORR_NORMED)

#convert result back to numpy array
resultNp = np.asarray(resultCv)

For just a 1-D cross-correlation create a 2-D array with shape equal to (N, 1 ). Though there is some extra code involved to convert to an openCV format the speed-up over scipy is quite impressive.

How to initialize const member variable in a class?

If a member is a Array it will be a little bit complex than the normal is:

class C
    static const int ARRAY[10];
    C() {}
const unsigned int C::ARRAY[10] = {0,1,2,3,4,5,6,7,8,9};


int* a = new int[N];
// fill a

class C {
  const std::vector<int> v;
  C():v(a, a+N) {}

wamp server does not start: Windows 7, 64Bit

I navigated to C:\wamp\bin\apache\Apache2.4.4\bin run httpd and the apache (pink and white icon) loads into the system tray. The orange W also turned green.

The apacheapache service wasn't running, it wasn't on the services list (start > type services) which is why it's orange not green.

Solution: A re-install worked for me.

My version is: WAMPSERVER (64Bits & PHP 5.4) 2.4 Apache : 2.4.4 MySQL : 5.6.12 PHP : 5.4.12 PHPMyAdmin : 4.0.4 SqlBuddy : 1.3.3 XDebug : 2.2.3

An Iframe I need to refresh every 30 seconds (but not the whole page)

add "id='myiframe'" to the iframe, then use this script :


function f1()
 var x=document.getElementById("myiframe");



console.log not working in Angular2 Component (Typescript)

Also try to update your browser because Angular need latest browser. check:

I fixed console.log issue after updating latest browser.

Magento addFieldToFilter: Two fields, match as OR, not AND

This is the real magento way:

                            'customer_firstname',//attribute_1 with key 0
                            'remote_ip',//attribute_2 with key 1
                            array('eq'=>'gabe'),//condition for attribute_1 with key 0
                            array('eq'=>''),//condition for attribute_2

Display Python datetime without time

>>> print, type(
2013-05-07 <type ''>

How to remove duplicate objects in a List<MyObject> without equals/hashcode?

Use set:

yourList = new ArrayList<Blog>(new LinkedHashSet<Blog>(yourList));

This will create list without duplicates and the element order will be as in original list.

Just do not forget to implement hashCode() and equals() for your class Blog.

More elegant "ps aux | grep -v grep"

You could use preg_split instead of explode and split on [ ]+ (one or more spaces). But I think in this case you could go with preg_match_all and capturing:

preg_match_all('/[ ]php[ ]+\S+[ ]+(\S+)/', $input, $matches);
$result = $matches[1];

The pattern matches a space, php, more spaces, a string of non-spaces (the path), more spaces, and then captures the next string of non-spaces. The first space is mostly to ensure that you don't match php as part of a user name but really only as a command.

An alternative to capturing is the "keep" feature of PCRE. If you use \K in the pattern, everything before it is discarded in the match:

preg_match_all('/[ ]php[ ]+\S+[ ]+\K\S+/', $input, $matches);
$result = $matches[0];

I would use preg_match(). I do something similar for many of my system management scripts. Here is an example:

$test = "user     12052  0.2  0.1 137184 13056 ?        Ss   10:00   0:00 php /home/user/public_html/utilities/runProcFile.php cust1 cron
user     12054  0.2  0.1 137184 13064 ?        Ss   10:00   0:00 php /home/user/public_html/utilities/runProcFile.php cust3 cron
user     12055  0.6  0.1 137844 14220 ?        Ss   10:00   0:00 php /home/user/public_html/utilities/runProcFile.php cust4 cron
user     12057  0.2  0.1 137184 13052 ?        Ss   10:00   0:00 php /home/user/public_html/utilities/runProcFile.php cust89 cron
user     12058  0.2  0.1 137184 13052 ?        Ss   10:00   0:00 php /home/user/public_html/utilities/runProcFile.php cust435 cron
user     12059  0.3  0.1 135112 13000 ?        Ss   10:00   0:00 php /home/user/public_html/utilities/runProcFile.php cust16 cron
root     12068  0.0  0.0 106088  1164 pts/1    S+   10:00   0:00 sh -c ps aux | grep utilities > /home/user/public_html/logs/dashboard/currentlyPosting.txt
root     12070  0.0  0.0 103240   828 pts/1    R+   10:00   0:00 grep utilities";

$lines = explode("\n", $test);

foreach($lines as $line){
        if(preg_match("/.php[\s+](cust[\d]+)[\s+]cron/i", $line, $matches)){


The above prints:

    [0] => .php cust1 cron
    [1] => cust1
    [0] => .php cust3 cron
    [1] => cust3
    [0] => .php cust4 cron
    [1] => cust4
    [0] => .php cust89 cron
    [1] => cust89
    [0] => .php cust435 cron
    [1] => cust435
    [0] => .php cust16 cron
    [1] => cust16

You can set $test to equal the output from exec. the values you are looking for would be in the if statement under the foreach. $matches[1] will have the custx value.

How can I indent multiple lines in Xcode?

In Xcode 4.2 auto-indenting is pretty good. You can now indent a selection of code by pressing the Tab key. I find that Xcode generally formats code really well automatically, and you rarely have to move things around yourself. I find it faster to select a piece of code, right-click and choose Structure -> Re-indent if some code looks messy.

Order a List (C#) by many fields?

Make your object something like

public class MyObject : IComparable
    public string a;
    public string b;

    virtual public int CompareTo(object obj)
        if (obj is MyObject)
            var compareObj = (MyObject)obj;
            if (this.a.CompareTo(compareObj.a) == 0)
                // compare second value
                return this.b.CompareTo(compareObj.b);
            return this.a.CompareTo(compareObj.b);
            throw new ArgumentException("Object is not a MyObject ");

also note that the returns for CompareTo :

Then, if you have a List of MyObject, call .Sort() ie

var objList = new List<MyObject>();

Maximum Java heap size of a 32-bit JVM on a 64-bit OS

The limitations of a 32-bit JVM on a 64-bit OS will be exactly the same as the limitations of a 32-bit JVM on a 32-bit OS. After all, the 32-bit JVM will be running In a 32-bit virtual machine (in the virtualization sense) so it won't know that it's running on a 64-bit OS/machine.

The one advantage to running a 32-bit JVM on a 64-bit OS versus a 32-bit OS is that you can have more physical memory, and therefore will encounter swapping/paging less frequently. This advantage is only really fully realized when you have multiple processes, however.

Retrieving a List from a in Java 8

A little more efficient way (avoid the creating the source List and the auto-unboxing by the filter):

List<Long> targetLongList = LongStream.of(1L, 10L, 50L, 80L, 100L, 120L, 133L, 333L)
    .filter(l -> l > 100)

Does C# have a String Tokenizer like Java's?

use Regex.Split(string,"#|#");

How to create an empty file at the command line in Windows?

Just I have tried in windows

copy con file.txt

then Press Enter Key then Press Ctrl+Z Enter

And its worked for me.

For Ubuntu usually I am creating a file using VI command

vi file.txt

It will open the file then press ESC key then type :wp then press enter key. It will create a new file with empty data.

Play an audio file using jQuery when a button is clicked

JSFiddle Demonstration

This is what I use with JQuery:

$('.button').on('click', function () { 
    var obj = document.createElement("audio");
        obj.src = "linktoyourfile.wav";; 

Bootstrap how to get text to vertical align in a div container


First, we will need to add a class to your text container so that we can access and style it accordingly.

<div class="col-xs-5 textContainer">
     <h3 class="text-left">Link up with other gamers all over the world who share the same tastes in games.</h3>


Next, we will apply the following styles to align it vertically, according to the size of the image div next to it.

.textContainer { 
    height: 345px; 
    line-height: 340px;

.textContainer h3 {
    vertical-align: middle;
    display: inline-block;

All Done! Adjust the line-height and height on the styles above if you believe that it is still slightly out of align.


Disabling the long-running-script message in Internet Explorer

I can't comment on the previous answers since I haven't tried them. However I know the following strategy works for me. It is a bit less elegant but gets the job done. It also doesn't require breaking code into chunks like some other approaches seem to do. In my case, that was not an option, because my code had recursive calls to the logic that was being looped; i.e., there was no practical way to just hop out of the loop, then be able to resume in some way by using global vars to preserve current state since those globals could be changed by references to them in a subsequent recursed call. So I needed a straight-forward way that would not offer a chance for the code to compromise the data state integrity.

Assuming the "stop script?" dialog is coming up during a for() loop executuion after a number of iterations (in my case, about 8-10), and messing with the registry is no option, here was the fix (for me, anyway):

var anarray = [];
var array_member = null;
var counter = 0; // Could also be initialized to the max desired value you want, if
                 // planning on counting downward.

function func_a()
 // some code
 // optionally, set 'counter' to some desired value.
 anarray = { populate array with objects to be processed that would have been
             processed by a for() }
 // 'anarry' is going to be reduced in size iteratively.  Therefore, if you need
 //  to maintain an orig. copy of it, create one, something like 'anarraycopy'.
 //  If you need only a shallow copy, use 'anarraycopy = anarray.slice(0);'
 //  A deep copy, depending on what kind of objects you have in the array, may be
 //  necessary.  The strategy for a deep copy will vary and is not discussed here.
 //  If you need merely to record the array's orig. size, set a local or
 //  global var equal to 'anarray.length;', depending on your needs.
 // - or -
 // plan to use 'counter' as if it was 'i' in a for(), as in
 // for(i=0; i < x; i++ {...}


   // Using 50 for example only.  Could be 100, etc. Good practice is to pick something
   // other than 0 due to Javascript engine processing; a 0 value is all but useless
   // since it takes time for Javascript to do anything. 50 seems to be good value to
   // use. It could be though that what value to use does  depend on how much time it
   // takes the code in func_c() to execute, so some profiling and knowing what the 
   // most likely deployed user base is going to be using might help. At the same 
   // time, this may make no difference.  Not entirely sure myself.  Also, 
   // using "'func_b()'" instead of just "func_b()" is critical.  I've found that the
   // callback will not occur unless you have the function in single-quotes.

   setTimeout('func_b()', 50);

  //  No more code after this.  function func_a() is now done.  It's important not to
  //  put any more code in after this point since setTimeout() does not act like
  //  Thread.sleep() in Java.  Processing just continues, and that is the problem
  //  you're trying to get around.

} // func_a()

function func_b()
 if( anarray.length == 0 )
   // possibly do something here, relevant to your purposes
//  -or- 
if( counter == x ) // 'x' is some value you want to go to.  It'll likely either
                   // be 0 (when counting down) or the max desired value you
                   // have for x if counting upward.
  // possibly do something here, relevant to your purposes

array_member = anarray[0];
anarray.splice(0,1); // Reduces 'anarray' by one member, the one at anarray[0].
                     // The one that was at anarray[1] is now at
                     // anarray[0] so will be used at the next iteration of func_b().


setTimeout('func_b()', 50);

} // func_b()

function func_c()
  counter++; // If not using 'anarray'.  Possibly you would use
             // 'counter--' if you set 'counter' to the highest value
             // desired and are working your way backwards.

  // Here is where you have the code that would have been executed
  // in the for() loop.  Breaking out of it or doing a 'continue'
  // equivalent can be done with using 'return;' or canceling 
  // processing entirely can be done by setting a global var
  // to indicate the process is cancelled, then doing a 'return;', as in
  // 'bCancelOut = true; return;'.  Then in func_b() you would be evaluating
  // bCancelOut at the top to see if it was true.  If so, you'd just exit from
  // func_b() with a 'return;'

} // func_c()

Crop image in android

I found a really cool library, try this out. this is really smooth and easy to use.

How to convert empty spaces into null values, using SQL Server?

Did you try this?

UPDATE table 
SET col1 = NULL 
WHERE col1 = ''

As the commenters point out, you don't have to do ltrim() or rtrim(), and NULL columns will not match ''.

Can't find keyplane that supports type 4 for keyboard iPhone-Portrait-NumberPad; using 3876877096_Portrait_iPhone-Simple-Pad_Default

I got the same error message for two separate reasons, so you can add them to your debugging checklist:

Context: Xcode 6.4, iOS:8.4. I was adding a toolbar with custom UIBarButtons to load with the UIKeyboardTypeNumberPad (Swift: UIKeyboardType.numberPad) , namely "Done" and "+/-". I had this problem when:

  1. My UIToolbar was declared as a property, but I had forgotten to explicitly alloc/init it.

  2. I had left off the last line, [myCustomToolbar sizeToFit];, which sounds like it's the same family as Holden's answer (my code here:

Good luck

Error: Local workspace file ('angular.json') could not be found

If you don't know the version ,current project has been made, you can omit --from command and type --migrate-only

ng update @angular/cli --migrate-only

Executing <script> injected by innerHTML after AJAX call

My conclusion is HTML doesn't allows NESTED SCRIPT tags. If you are using javascript for injecting HTML code that include script tags inside is not going to work because the javascript goes in a script tag too. You can test it with the next code and you will be that it's not going to work. The use case is you are calling a service with AJAX or similar, you are getting HTML and you want to inject it in the HTML DOM straight forward. If the injected HTML code has inside SCRIPT tags is not going to work.

<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"></head><body></body><script>document.getElementsByTagName("body")[0].innerHTML = "<script>console.log('hi there')</script>\n<div>hello world</div>\n"</script></html>

Check if a row exists using old mysql_* API

Use mysql_num_rows(), to check if rows are available or not

$result = mysql_query("SELECT * FROM preditors_assigned WHERE lecture_name='$lectureName' LIMIT 1");
$num_rows = mysql_num_rows($result);

if ($num_rows > 0) {
  // do something
else {
  // do something else

Error: Registry key 'Software\JavaSoft\Java Runtime Environment'\CurrentVersion'?

I just uninstalled my Java8 update and tried again. It worked ok!

ASP.NET MVC5/IIS Express unable to debug - Code Not Running

Resolution fix: For me, the problem was related to active chrome sessions. I closed all of my chrome browser sessions and then tried building to chrome again. I am using Visual Studio Professional 2017 version 15.3.2. The VS application I was running into build errors with was a WebAPI project. When trying to click the green play button, I was getting dialog error stating "Unable to start the program 'http://localhost:18980/'. An operation is not legal in the current state. Hopefully this post helps someone.

How to get Selected Text from select2 when using <input>

Also you can have the selected value using following code:

alert("Selected option value is: "+$('#SelectelementId').select2("val"));

Using :before CSS pseudo element to add image to modal

::after and ::before with content are better to use as they're supported in every major browser other than Internet Explorer at least 5 versions back. Internet Explorer has complete support in version 9+ and partial support in version 8.

Is this what you're looking for?

  content:url('blackCarrot.png'); /* with class ModalCarrot ??*/
  position:relative; /*or absolute*/
  z-index:100000; /*a number that's more than the modal box*/


If not, can you explain a little better?

or you could use jQuery, like Joshua said:

$(".Modal").before("<img src='blackCarrot.png' class='ModalCarrot' />");

Remove or uninstall library previously added : cocoapods

Remove lib from Podfile, then pod install again.

How to remove a newline from a string in Bash

Clean your variable by removing all the carriage returns:

COMMAND=$(echo $COMMAND|tr -d '\n')

Java: How can I compile an entire directory structure of code ?

Following is the method I found:

1) Make a list of files with relative paths in a file (say FilesList.txt) as follows (either space separated or line separated):


2) Use the command:

javac @FilesList.txt -d classes

This will compile all the files and put the class files inside classes directory.

Now easy way to create FilesList.txt is this: Go to your source root directory.

dir *.java /s /b > FilesList.txt

But, this will populate absolute path. Using a text editor "Replace All" the path up to source directory (include \ in the end) with "" (i.e. empty string) and Save.

Adding a Button to a WPF DataGrid

Check this out:


<DataGrid Name="DataGrid1">
                    <Button Click="ChangeText">Show/Hide</Button>


private void ChangeText(object sender, RoutedEventArgs e)
    DemoModel model = (sender as Button).DataContext as DemoModel;
    model.DynamicText = (new Random().Next(0, 100).ToString());


class DemoModel : INotifyPropertyChanged
    protected String _text;
    public String Text
        get { return _text; }
        set { _text = value; RaisePropertyChanged("Text"); }

    protected String _dynamicText;
    public String DynamicText
        get { return _dynamicText; }
        set { _dynamicText = value; RaisePropertyChanged("DynamicText"); }

    public event PropertyChangedEventHandler PropertyChanged;
    public void RaisePropertyChanged(String propertyName)
        PropertyChangedEventHandler temp = PropertyChanged;
        if (temp != null)
            temp(this, new PropertyChangedEventArgs(propertyName));

Initialization Code:

ObservableCollection<DemoModel> models = new ObservableCollection<DemoModel>();
models.Add(new DemoModel() { Text = "Some Text #1." });
models.Add(new DemoModel() { Text = "Some Text #2." });
models.Add(new DemoModel() { Text = "Some Text #3." });
models.Add(new DemoModel() { Text = "Some Text #4." });
models.Add(new DemoModel() { Text = "Some Text #5." });
DataGrid1.ItemsSource = models;

How to create a JSON object

$post_data = [
  "item" => [
    'item_type_id' => $item_type,
    'string_key' => $string_key,
    'string_value' => $string_value,
    'string_extra' => $string_extra,
    'is_public' => $public,
    'is_public_for_contacts' => $public_contacts

$post_data = json_encode(post_data);
$post_data = json_decode(post_data);
return $post_data;

How to manually update datatables table with new JSON data

In my case, I am not using the built in ajax api to feed Json to the table (this is due to some formatting that was rather difficult to implement inside the datatable's render callback).

My solution was to create the variable in the outer scope of the onload functions and the function that handles the data refresh (var table = null, for example).

Then I instantiate my table in the on load method

$(function () {
            //.... some code here
            table = $("#detailReportTable").DataTable();
            .... more code here

and finally, in the function that handles the refresh, i invoke the clear() and destroy() method, fetch the data into the html table, and re-instantiate the datatable, as such:

function getOrderDetail() {
             //.....api call here
            table = $("#detailReportTable").DataTable();

I hope someone finds this useful!

Apply CSS styles to an element depending on its child elements

As far as I'm aware, styling a parent element based on the child element is not an available feature of CSS. You'll likely need scripting for this.

It'd be wonderful if you could do something like div[div.a] or div:containing[div.a] as you said, but this isn't possible.

You may want to consider looking at jQuery. Its selectors work very well with 'containing' types. You can select the div, based on its child contents and then apply a CSS class to the parent all in one line.

If you use jQuery, something along the lines of this would may work (untested but the theory is there):

$('div:has(div.a)').css('border', '1px solid red');



combined with a CSS class:

    border: 1px solid red;

Here's the documentation for the jQuery "has" selector.

How do I rename the extension for a bunch of files?

Here is what i used to rename .edge files to .blade.php

for file in *.edge; do     mv "$file" "$(basename "$file" .edge).blade.php"; done

Works like charm.

What does $ mean before a string?

Cool feature. I just want to point out the emphasis on why this is better than string.format if it is not apparent to some people.

I read someone saying order string.format to "{0} {1} {2}" to match the parameters. You are not forced to order "{0} {1} {2}" in string.format, you can also do "{2} {0} {1}". However, if you have a lot of parameters, like 20, you really want to sequence the string to "{0} {1} {2} ... {19}". If it is a shuffled mess, you will have a hard time lining up your parameters.

With $, you can add parameter inline without counting your parameters. This makes the code much easier to read and maintain.

The downside of $ is, you cannot repeat the parameter in the string easily, you have to type it. For example, if you are tired of typing System.Environment.NewLine, you can do string.format("...{0}...{0}...{0}", System.Environment.NewLine), but, in $, you have to repeat it. You cannot do $"{0}" and pass it to string.format because $"{0}" returns "0".

On the side note, I have read a comment in another duplicated tpoic. I couldn't comment, so, here it is. He said that

string msg = n + " sheep, " + m + " chickens";

creates more than one string objects. This is not true actually. If you do this in a single line, it only creates one string and placed in the string cache.

1) string + string + string + string;
2) string.format()
3) stringBuilder.ToString()
4) $""

All of them return a string and only creates one value in the cache.

On the other hand:

string+= string2;
string+= string2;
string+= string2;
string+= string2;

Creates 4 different values in the cache because there are 4 ";".

Thus, it will be easier to write code like the following, but you would create five interpolated string as Carlos Muñoz corrected:

string msg = $"Hello this is {myName}, " +
  $"My phone number {myPhone}, " +
  $"My email {myEmail}, " +
  $"My address {myAddress}, and " +
  $"My preference {myPreference}.";

This creates one single string in the cache while you have very easy to read code. I am not sure about the performance, but, I am sure MS will optimize it if not already doing it.

Unit tests vs Functional tests

Unit tests tell a developer that the code is doing things right; functional tests tell a developer that the code is doing the right things.

You can read more at Unit Testing versus Functional Testing

A well explained real-life analogy of unit testing and functional testing can be described as follows,

Many times the development of a system is likened to the building of a house. While this analogy isn't quite correct, we can extend it for the purposes of understanding the difference between unit and functional tests.

Unit testing is analogous to a building inspector visiting a house's construction site. He is focused on the various internal systems of the house, the foundation, framing, electrical, plumbing, and so on. He ensures (tests) that the parts of the house will work correctly and safely, that is, meet the building code.

Functional tests in this scenario are analogous to the homeowner visiting this same construction site. He assumes that the internal systems will behave appropriately, that the building inspector is performing his task. The homeowner is focused on what it will be like to live in this house. He is concerned with how the house looks, are the various rooms a comfortable size, does the house fit the family's needs, are the windows in a good spot to catch the morning sun.

The homeowner is performing functional tests on the house. He has the user's perspective.

The building inspector is performing unit tests on the house. He has the builder's perspective.

As a summary,

Unit Tests are written from a programmers perspective. They are made to ensure that a particular method (or a unit) of a class performs a set of specific tasks.

Functional Tests are written from the user's perspective. They ensure that the system is functioning as users are expecting it to.

How to use the unsigned Integer in Java 8 and Java 9?

If using a third party library is an option, there is jOOU (a spin off library from jOOQ), which offers wrapper types for unsigned integer numbers in Java. That's not exactly the same thing as having primitive type (and thus byte code) support for unsigned types, but perhaps it's still good enough for your use-case.

import static org.joou.Unsigned.*;

// and then...
UByte    b = ubyte(1);
UShort   s = ushort(1);
UInteger i = uint(1);
ULong    l = ulong(1);

All of these types extend java.lang.Number and can be converted into higher-order primitive types and BigInteger.

(Disclaimer: I work for the company behind these libraries)

PHPExcel How to apply styles and set cell width and cell height to cell generated dynamically

Try this:


Find Number of CPUs and Cores per CPU using Command Prompt

In order to check the absence of physical sockets run:

wmic cpu get SocketDesignation

How to declare empty list and then add string in scala?

As mentioned in an above answer, the Scala List is an immutable collection. You can create an empty list with .empty[A]. Then you can use a method :+ , +: or :: in order to add element to the list.

scala> val strList = List.empty[String]
strList: List[String] = List()

scala> strList:+ "Text"
res3: List[String] = List(Text)

scala> val mapList = List.empty[Map[String, Any]]
mapList: List[Map[String,Any]] = List()

scala> mapList :+ Map("1" -> "ok")
res4: List[Map[String,Any]] = List(Map(1 -> ok))

Crystal Reports - Adding a parameter to a 'Command' query

Select Projecttname, ReleaseDate, TaskName From DB_Table Where Project_Name like '%{?Pm-?Proj_Name}%' and ReleaseDate >= currentdate

Note the single-quotes and wildcard characters. I just spent 30 minutes figuring out something similar.

JavaScript associative array to JSON

Agreed that it is probably best practice to keep Objects as objects and Arrays as arrays. However, if you have an Object with named properties that you are treating as an array, here is how it can be done:

let tempArr = [];
Object.keys(objectArr).forEach( (element) => {

let json = JSON.stringify(tempArr);

Exception : AAPT2 error: check logs for details

some symbols should be transferred like '%'

<string name="test" formatted="false">95%</string>

running a command as a super user from a python script

Try:['sudo', 'apach2ctl', 'restart'])

The subprocess needs to access the real stdin/out/err for it to be able to prompt you, and read in your password. If you set them up as pipes, you need to feed the password into that pipe yourself.

If you don't define them, then it grabs sys.stdout, etc...