Programs & Examples On #Envjs

EnvJS is a simulated JavaScript browser

Bootstrap 3 Gutter Size

Bootstrap 3 introduced row-no-gutters in v3.4.0

https://getbootstrap.com/docs/3.4/css/#grid-remove-gutters

You could make a row without gutters, and have a row with gutters inside it for the parts you do want to have a gutter.

Proper MIME type for OTF fonts

FWIW regarding Apache 2.2 VirtualHosting and mod_mime tested on Debian Linux and OS X Leopard and Snow Leopard:

If you have a VirtualHost configuration you will want to add the types via the AddType Directive as follows at least at the bottom of the configuration as follows:

....
   AddType font/opentype .otf
   AddType font/ttf .ttf
</VirtualHost>

Tested against Chrome Unstable/Trunk and Safari WebKit Nightly which eliminates the mime octet-stream warnings for both the ttf and otf font types.

Note: .htaccess has zero effect when dealing with VirtualHosting. If you're developing for several sites you'll be using VirtualHosting development and each configuration will need these AddType additions.

Strange problem with Subversion - "File already exists" when trying to recreate a directory that USED to be in my repository

What you need is the svn 'export' command. With this you can put a file or entire directory tree in the state of another revision in another branch.

So something like

rm file #without 'svn' in front!
svn export myrepo/path/to/file@<revision> .
svn commit

estimating of testing effort as a percentage of development time

Testing time is probably more closely correlated to feature scope than development time. I'd also argue (perhaps controversially) that testing time is correlated to the skill of your development team.

For a 6-to-9 month development effort, I demand a absolute minimum of 2 weeks testing time, performed by actual testers (not the development team) who are well-versed in the software they will be testing (i.e., 2 weeks does not include ramp-up time). This is for a project that has ~5 developers.

Java says FileNotFoundException but file exists

I had this same error and solved it simply by adding the src directory that is found in Java project structure.

String path = System.getProperty("user.dir") + "\\src\\package_name\\file_name";
File file = new File(path);
Scanner scanner = new Scanner(file);

Notice that System.getProperty("user.dir") and new File(".").getAbsolutePath() return your project root directory path, so you have to add the path to your subdirectories and packages

Finding modified date of a file/folder

PowerShell code to find all document library files modified from last 2 days.

$web = Get-SPWeb -Identity http://siteName:9090/ 
        $list = $web.GetList("http://siteName:9090/Style Library/")
        $folderquery =  New-Object Microsoft.SharePoint.SPQuery  
        $foldercamlQuery =  
        '<Where>   <Eq> 
                <FieldRef Name="ContentType" />  <Value Type="text">Folder</Value> 
            </Eq> </Where>' 
        $folderquery.Query = $foldercamlQuery 
        $folders = $list.GetItems($folderquery) 
        foreach($folderItem in $folders) 
        { 
            $folder = $folderItem.Folder
            if($folder.ItemCount -gt 0){ 
            Write-Host " find Item count " $folder.ItemCount
                $oldest = $null
                $files = $folder.Files

                $date = (Get-Date).AddDays(-2).ToString(“MM/dd/yyyy”)
                foreach ($file in $files){ 
                    if($file.Item["Modified"]-Ge $date)
                    {
                        Write-Host "Last 2 days modified folder name:"   $folder   " File Name: "  $file.Item["Name"]   " Date of midified: "  $file.Item["Modified"] 
                    } 
                } 
            } 
            else
             { 
                Write-Warning "$folder['Name'] is empty" 
            } 
        }

ansible: lineinfile for several lines?

To add multiple lines you can use lineinfile module with with_items also including variable vars here to make it simple :)

---
- hosts: localhost  #change Host group as par inventory
  gather_facts: no
  become: yes
  vars:
    test_server: "10.168.1.1"
    test_server_name: "test-server"
    file_dest: "/etc/test/test_agentd.conf"

  - name: configuring test.conf
    lineinfile:
      dest: "{{ item.dest }}"
      regexp: "{{ item.regexp }}"
      line: "{{ item.line }}"
    with_items:
      - { dest: '"{{ file_dest }}"', regexp: 'Server=', line: 'Server="{{test_server}}"' }
      - { dest: '"{{ file_dest }}"', regexp: 'ServerActive=', line: 'ServerActive="{{test_server}}"' }
      - { dest: '"{{ file_dest }}"', regexp: 'Hostname=', line: 'Hostname="{{test_server_name}}"' }

VBA macro that search for file in multiple subfolders

This sub will populate a Collection with all files matching the filename or pattern you pass in.

Sub GetFiles(StartFolder As String, Pattern As String, _
             DoSubfolders As Boolean, ByRef colFiles As Collection)

    Dim f As String, sf As String, subF As New Collection, s
    
    If Right(StartFolder, 1) <> "\" Then StartFolder = StartFolder & "\"
    
    f = Dir(StartFolder & Pattern)
    Do While Len(f) > 0
        colFiles.Add StartFolder & f
        f = Dir()
    Loop
    
    If DoSubfolders then
        sf = Dir(StartFolder, vbDirectory)
        Do While Len(sf) > 0
            If sf <> "." And sf <> ".." Then
                If (GetAttr(StartFolder & sf) And vbDirectory) <> 0 Then
                        subF.Add StartFolder & sf
                End If
            End If
            sf = Dir()
        Loop
    
        For Each s In subF
            GetFiles CStr(s), Pattern, True, colFiles
        Next s
    End If

End Sub

Usage:

Dim colFiles As New Collection

GetFiles "C:\Users\Marek\Desktop\Makro\", FName & ".xls", True, colFiles
If colFiles.Count > 0 Then
    'work with found files
End If

Send email using the GMail SMTP server from a PHP page

<?php
date_default_timezone_set('America/Toronto');

require_once('class.phpmailer.php');
//include("class.smtp.php"); // optional, gets called from within class.phpmailer.php if not already loaded

$mail             = new PHPMailer();

$body             = "gdssdh";
//$body             = eregi_replace("[\]",'',$body);

$mail->IsSMTP(); // telling the class to use SMTP
//$mail->Host       = "ssl://smtp.gmail.com"; // SMTP server
$mail->SMTPDebug  = 1;                     // enables SMTP debug information (for testing)
                                           // 1 = errors and messages
                                           // 2 = messages only
$mail->SMTPAuth   = true;                  // enable SMTP authentication
$mail->SMTPSecure = "ssl";                 // sets the prefix to the servier
$mail->Host       = "smtp.gmail.com";      // sets GMAIL as the SMTP server
$mail->Port       = 465;                   // set the SMTP port for the GMAIL server
$mail->Username   = "[email protected]";  // GMAIL username
$mail->Password   = "password";            // GMAIL password

$mail->SetFrom('[email protected]', 'PRSPS');

//$mail->AddReplyTo("[email protected]', 'First Last");

$mail->Subject    = "PRSPS password";

//$mail->AltBody    = "To view the message, please use an HTML compatible email viewer!"; // optional, comment out and test

$mail->MsgHTML($body);

$address = "[email protected]";
$mail->AddAddress($address, "user2");

//$mail->AddAttachment("images/phpmailer.gif");      // attachment
//$mail->AddAttachment("images/phpmailer_mini.gif"); // attachment

if(!$mail->Send()) {
  echo "Mailer Error: " . $mail->ErrorInfo;
} else {
  echo "Message sent!";
}

?>

How to swap two variables in JavaScript

We are able to swap var like this :

var val1 =  117,
    val2 = 327;

val2 = val1-val2; 
console.log(val2);
val1 = val1-val2;
console.log(val1);
val2 = val1+val2;
console.log(val2);

How to initialize weights in PyTorch?

    import torch.nn as nn        

    # a simple network
    rand_net = nn.Sequential(nn.Linear(in_features, h_size),
                             nn.BatchNorm1d(h_size),
                             nn.ReLU(),
                             nn.Linear(h_size, h_size),
                             nn.BatchNorm1d(h_size),
                             nn.ReLU(),
                             nn.Linear(h_size, 1),
                             nn.ReLU())

    # initialization function, first checks the module type,
    # then applies the desired changes to the weights
    def init_normal(m):
        if type(m) == nn.Linear:
            nn.init.uniform_(m.weight)

    # use the modules apply function to recursively apply the initialization
    rand_net.apply(init_normal)

Rename Oracle Table or View

Past 10g the current answer no longer works for renaming views. The only method that still works is dropping and recreating the view. The best way I can think of to do this would be:

SELECT TEXT FROM ALL_VIEWS WHERE owner='some_schema' and VIEW_NAME='some_view';

Add this in front of the SQL returned

Create or replace view some_schema.new_view_name as ...

Drop the old view

Drop view some_schema.some_view;

What is the instanceof operator in JavaScript?

instanceof

The Left Hand Side (LHS) operand is the actual object being tested to the Right Hand Side (RHS) operand which is the actual constructor of a class. The basic definition is:

Checks the current object and returns true if the object
is of the specified object type.

Here are some good examples and here is an example taken directly from Mozilla's developer site:

var color1 = new String("green");
color1 instanceof String; // returns true
var color2 = "coral"; //no type specified
color2 instanceof String; // returns false (color2 is not a String object)

One thing worth mentioning is instanceof evaluates to true if the object inherits from the classe's prototype:

var p = new Person("Jon");
p instanceof Person

That is p instanceof Person is true since p inherits from Person.prototype.

Per the OP's request

I've added a small example with some sample code and an explanation.

When you declare a variable you give it a specific type.

For instance:

int i;
float f;
Customer c;

The above show you some variables, namely i, f, and c. The types are integer, float and a user defined Customer data type. Types such as the above could be for any language, not just JavaScript. However, with JavaScript when you declare a variable you don't explicitly define a type, var x, x could be a number / string / a user defined data type. So what instanceof does is it checks the object to see if it is of the type specified so from above taking the Customer object we could do:

var c = new Customer();
c instanceof Customer; //Returns true as c is just a customer
c instanceof String; //Returns false as c is not a string, it's a customer silly!

Above we've seen that c was declared with the type Customer. We've new'd it and checked whether it is of type Customer or not. Sure is, it returns true. Then still using the Customer object we check if it is a String. Nope, definitely not a String we newed a Customer object not a String object. In this case, it returns false.

It really is that simple!

How to normalize an array in NumPy to a unit vector?

I would agree that it were nice if such a function was part of the included batteries. But it isn't, as far as I know. Here is a version for arbitrary axes, and giving optimal performance.

import numpy as np

def normalized(a, axis=-1, order=2):
    l2 = np.atleast_1d(np.linalg.norm(a, order, axis))
    l2[l2==0] = 1
    return a / np.expand_dims(l2, axis)

A = np.random.randn(3,3,3)
print(normalized(A,0))
print(normalized(A,1))
print(normalized(A,2))

print(normalized(np.arange(3)[:,None]))
print(normalized(np.arange(3)))

CSS3 Transparency + Gradient

I just came across this more recent example . To simplify and use the most recent examples, giving the css a selector class of 'grad',(I've included backwards compatibility)

.grad {
    background-color: #F07575; /* fallback color if gradients are not supported */
    background-image: -webkit-linear-gradient(top left, red, rgba(255,0,0,0));/* For Chrome 25 and Safari 6, iOS 6.1, Android 4.3 */
    background-image: -moz-linear-gradient(top left, red, rgba(255,0,0,0));/* For Firefox (3.6 to 15) */
    background-image: -o-linear-gradient(top left, red, rgba(255,0,0,0));/* For old Opera (11.1 to 12.0) */
    background-image: linear-gradient(to bottom right, red, rgba(255,0,0,0)); /* Standard syntax; must be last */
}

from https://developer.mozilla.org/en-US/docs/Web/CSS/linear-gradient

Ruby function to remove all white spaces?

If you want to remove only leading and trailing whitespace (like PHP's trim) you can use .strip, but if you want to remove all whitespace, you can use .gsub(/\s+/, "") instead .

How to fix Terminal not loading ~/.bashrc on OS X Lion

I have the following in my ~/.bash_profile:

if [ -f ~/.bashrc ]; then . ~/.bashrc; fi

If I had .bashrc instead of ~/.bashrc, I'd be seeing the same symptom you're seeing.

Save a list to a .txt file

Try this, if it helps you

values = ['1', '2', '3']

with open("file.txt", "w") as output:
    output.write(str(values))

How do I load a file from resource folder?

I get it to work without any reference to "class" or "ClassLoader".

Let's say we have three scenarios with the location of the file 'example.file' and your working directory (where your app executes) is home/mydocuments/program/projects/myapp:

a)A sub folder descendant to the working directory: myapp/res/files/example.file

b)A sub folder not descendant to the working directory: projects/files/example.file

b2)Another sub folder not descendant to the working directory: program/files/example.file

c)A root folder: home/mydocuments/files/example.file (Linux; in Windows replace home/ with C:)

1) Get the right path: a)String path = "res/files/example.file"; b)String path = "../projects/files/example.file" b2)String path = "../../program/files/example.file" c)String path = "/home/mydocuments/files/example.file"

Basically, if it is a root folder, start the path name with a leading slash. If it is a sub folder, no slash must be before the path name. If the sub folder is not descendant to the working directory you have to cd to it using "../". This tells the system to go up one folder.

2) Create a File object by passing the right path:

File file = new File(path);

3) You are now good to go:

BufferedReader br = new BufferedReader(new FileReader(file));

How do I install imagemagick with homebrew?

You could try:

brew update && brew install imagemagick

How to choose the id generation strategy when using JPA and Hibernate

Basically, you have two major choices:

  • You can generate the identifier yourself, in which case you can use an assigned identifier.
  • You can use the @GeneratedValue annotation and Hibernate will assign the identifier for you.

For the generated identifiers you have two options:

  • UUID identifiers.
  • Numerical identifiers.

For numerical identifiers you have three options:

  • IDENTITY
  • SEQUENCE
  • TABLE

IDENTITY is only a good choice when you cannot use SEQUENCE (e.g. MySQL) because it disables JDBC batch updates.

SEQUENCE is the preferred option, especially when used with an identifier optimizer like pooled or pooled-lo.

TABLE is to be avoided since it uses a separate transaction to fetch the identifier and row-level locks which scales poorly.

How to get names of enum entries?

Assuming you stick to the rules and only produce enums with numeric values, you can use this code. This correctly handles the case where you have a name that is coincidentally a valid number

enum Color {
    Red,
    Green,
    Blue,
    "10" // wat
}

var names: string[] = [];
for(var n in Color) {
    if(typeof Color[n] === 'number') names.push(n);
}
console.log(names); // ['Red', 'Green', 'Blue', '10']

What should I do if the current ASP.NET session is null?

If your Session instance is null and your in an 'ashx' file, just implement the 'IRequiresSessionState' interface.

This interface doesn't have any members so you just need to add the interface name after the class declaration (C#):

public class MyAshxClass : IHttpHandler, IRequiresSessionState

Control the dashed border stroke length and distance between strokes

In addition to the border-image property, there are a few other ways to create a dashed border with control over the length of the stroke and the distance between them. They are described below:

Method 1: Using SVG

We can create the dashed border by using a path or a polygon element and setting the stroke-dasharray property. The property takes two parameters where one defines the size of the dash and the other determines the space between them.

Pros:

  1. SVGs by nature are scalable graphics and can adapt to any container dimensions.
  2. Can work very well even if there is a border-radius involved. We would just have replace the path with a circle like in this answer (or) convert the path into a circle.
  3. Browser support for SVG is pretty good and fallback can be provided using VML for IE8-.

Cons:

  1. When the dimensions of the container do not change proportionately, the paths tend to scale resulting in a change in size of the dash and the space between them (try hovering on the first box in the snippet). This can be controlled by adding vector-effect='non-scaling-stroke' (as in the second box) but the browser support for this property is nil in IE.

_x000D_
_x000D_
.dashed-vector {_x000D_
  position: relative;_x000D_
  height: 100px;_x000D_
  width: 300px;_x000D_
}_x000D_
svg {_x000D_
  position: absolute;_x000D_
  top: 0px;_x000D_
  left: 0px;_x000D_
  height: 100%;_x000D_
  width: 100%;_x000D_
}_x000D_
path{_x000D_
  fill: none;_x000D_
  stroke: blue;_x000D_
  stroke-width: 5;_x000D_
  stroke-dasharray: 10, 10;_x000D_
}_x000D_
span {_x000D_
  position: absolute;_x000D_
  top: 0px;_x000D_
  left: 0px;_x000D_
  padding: 10px;_x000D_
}_x000D_
_x000D_
_x000D_
/* just for demo */_x000D_
_x000D_
div{_x000D_
  margin-bottom: 10px;_x000D_
  transition: all 1s;_x000D_
}_x000D_
div:hover{_x000D_
  height: 100px;_x000D_
  width: 400px;_x000D_
}
_x000D_
<div class='dashed-vector'>_x000D_
  <svg viewBox='0 0 300 100' preserveAspectRatio='none'>_x000D_
    <path d='M0,0 300,0 300,100 0,100z' />_x000D_
  </svg>_x000D_
  <span>Some content</span>_x000D_
</div>_x000D_
_x000D_
<div class='dashed-vector'>_x000D_
  <svg viewBox='0 0 300 100' preserveAspectRatio='none'>_x000D_
    <path d='M0,0 300,0 300,100 0,100z' vector-effect='non-scaling-stroke'/>_x000D_
  </svg>_x000D_
  <span>Some content</span>_x000D_
</div>
_x000D_
_x000D_
_x000D_


Method 2: Using Gradients

We can use multiple linear-gradient background images and position them appropriately to create a dashed border effect. This can also be done with a repeating-linear-gradient but there is not much improvement because of using a repeating gradient as we need each gradient to repeat in only one direction.

_x000D_
_x000D_
.dashed-gradient{_x000D_
  height: 100px;_x000D_
  width: 200px;_x000D_
  padding: 10px;_x000D_
  background-image: linear-gradient(to right, blue 50%, transparent 50%), linear-gradient(to right, blue 50%, transparent 50%), linear-gradient(to bottom, blue 50%, transparent 50%), linear-gradient(to bottom, blue 50%, transparent 50%);_x000D_
  background-position: left top, left bottom, left top, right top;_x000D_
  background-repeat: repeat-x, repeat-x, repeat-y, repeat-y;_x000D_
  background-size: 20px 3px, 20px 3px, 3px 20px, 3px 20px;_x000D_
}_x000D_
_x000D_
.dashed-repeating-gradient {_x000D_
  height: 100px;_x000D_
  width: 200px;_x000D_
  padding: 10px;_x000D_
  background-image: repeating-linear-gradient(to right, blue 0%, blue 50%, transparent 50%, transparent 100%), repeating-linear-gradient(to right, blue 0%, blue 50%, transparent 50%, transparent 100%), repeating-linear-gradient(to bottom, blue 0%, blue 50%, transparent 50%, transparent 100%), repeating-linear-gradient(to bottom, blue 0%, blue 50%, transparent 50%, transparent 100%);_x000D_
  background-position: left top, left bottom, left top, right top;_x000D_
  background-repeat: repeat-x, repeat-x, repeat-y, repeat-y;_x000D_
  background-size: 20px 3px, 20px 3px, 3px 20px, 3px 20px;_x000D_
}_x000D_
_x000D_
/* just for demo */_x000D_
_x000D_
div {_x000D_
  margin: 10px;_x000D_
  transition: all 1s;_x000D_
}_x000D_
div:hover {_x000D_
  height: 150px;_x000D_
  width: 300px;_x000D_
}
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/prefixfree/1.0.7/prefixfree.min.js"></script>_x000D_
<div class='dashed-gradient'>Some content</div>_x000D_
<div class='dashed-repeating-gradient'>Some content</div>
_x000D_
_x000D_
_x000D_

Pros:

  1. Scalable and can adapt even if the container's dimensions are dynamic.
  2. Does not make use of any extra pseudo-elements which means they can be kept aside for any other potential usage.

Cons:

  1. Browser support for linear gradients is comparatively lower and this is a no-go if you want to support IE 9-. Even libraries like CSS3 PIE do not support creation of gradient patterns in IE8-.
  2. Cannot be used when border-radius is involved because backgrounds don't curve based on border-radius. They get clipped instead.

Method 3: Box Shadows

We can create a small bar (in the shape of the dash) using pseudo-elements and then create multiple box-shadow versions of it to create a border like in the below snippet.

If the dash is a square shape then a single pseudo-element would be enough but if it is a rectangle, we would need one pseudo-element for the top + bottom borders and another for left + right borders. This is because the height and width for the dash on the top border will be different from that on the left.

Pros:

  1. The dimensions of the dash is controllable by changing the dimensions of the pseudo-element. The spacing is controllable by modifying the space between each shadow.
  2. A very unique effect can be produced by adding a different color for each box shadow.

Cons:

  1. Since we have to manually set the dimensions of the dash and the spacing, this approach is no good when the dimensions of the parent box is dynamic.
  2. IE8 and lower do not support box shadow. However, this can be overcome by using libraries like CSS3 PIE.
  3. Can be used with border-radius but positioning them would be very tricky with having to find points on a circle (and possibly even transform).

_x000D_
_x000D_
.dashed-box-shadow{_x000D_
  position: relative;_x000D_
  height: 120px;_x000D_
  width: 120px;_x000D_
  padding: 10px;_x000D_
}_x000D_
.dashed-box-shadow:before{ /* for border top and bottom */_x000D_
  position: absolute;_x000D_
  content: '';_x000D_
  top: 0px;_x000D_
  left: 0px;_x000D_
  height: 3px; /* height of the border top and bottom */_x000D_
  width: 10px; /* width of the border top and bottom */_x000D_
  background: blue; /* border color */_x000D_
  box-shadow: 20px 0px 0px blue, 40px 0px 0px blue, 60px 0px 0px blue, 80px 0px 0px blue, 100px 0px 0px blue, /* top border */_x000D_
    0px 110px 0px blue, 20px 110px 0px blue, 40px 110px 0px blue, 60px 110px 0px blue, 80px 110px 0px blue, 100px 110px 0px blue; /* bottom border */_x000D_
}_x000D_
.dashed-box-shadow:after{ /* for border left and right */_x000D_
  position: absolute;_x000D_
  content: '';_x000D_
  top: 0px;_x000D_
  left: 0px;_x000D_
  height: 10px; /* height of the border left and right */_x000D_
  width: 3px; /* width of the border left and right */_x000D_
  background: blue; /* border color */_x000D_
  box-shadow: 0px 20px 0px blue, 0px 40px 0px blue, 0px 60px 0px blue, 0px 80px 0px blue, 0px 100px 0px blue, /* left border */_x000D_
    110px 0px 0px blue, 110px 20px 0px blue, 110px 40px 0px blue, 110px 60px 0px blue, 110px 80px 0px blue, 110px 100px 0px blue; /* right border */_x000D_
}
_x000D_
<div class='dashed-box-shadow'>Some content</div>
_x000D_
_x000D_
_x000D_

String index out of range: 4

You are using the wrong iteration counter, replace inp.charAt(i) with inp.charAt(j).

LIKE operator in LINQ

   public static class StringEx
    {
        public static bool Contains(this String str, string[] Arr, StringComparison comp)
        {
            if (Arr != null)
            {
                foreach (string s in Arr)
                {
                    if (str.IndexOf(s, comp)>=0)
                    { return true; }
                }
            }

            return false;
        }

        public static bool Contains(this String str,string[] Arr)
        {
            if (Arr != null)
            {
                foreach (string s in Arr)
                {
                    if (str.Contains(s))
                    { return true; }
                }
            }

            return false;
        }
    }


var portCode = Database.DischargePorts
                   .Single(p => p.PortName.Contains( new string[] {"BALTIMORE"},  StringComparison.CurrentCultureIgnoreCase) ))
                   .PortCode;

Detecting an "invalid date" Date instance in JavaScript

You can simply use moment.js

Here is an example:

var m = moment('2015-11-32', 'YYYY-MM-DD');
m.isValid(); // false

The validation section in the documentation is quite clear.

And also, the following parsing flags result in an invalid date:

  • overflow: An overflow of a date field, such as a 13th month, a 32nd day of the month (or a 29th of February on non-leap years), a 367th day of the year, etc. overflow contains the index of the invalid unit to match #invalidAt (see below); -1 means no overflow.
  • invalidMonth: An invalid month name, such as moment('Marbruary', 'MMMM');. Contains the invalid month string itself, or else null.
  • empty: An input string that contains nothing parsable, such as moment('this is nonsense');. Boolean.
  • Etc.

Source: http://momentjs.com/docs/

Django: Model Form "object has no attribute 'cleaned_data'"

For some reason, you're re-instantiating the form after you check is_valid(). Forms only get a cleaned_data attribute when is_valid() has been called, and you haven't called it on this new, second instance.

Just get rid of the second form = SearchForm(request.POST) and all should be well.

How do I change the font-size of an <option> element within <select>?

One solution could be to wrap the options inside optgroup:

_x000D_
_x000D_
optgroup { font-size:40px; }
_x000D_
<select>
  <optgroup>
    <option selected="selected" class="service-small">Service area?</option>
    <option class="service-small">Volunteering</option>
    <option class="service-small">Partnership &amp; Support</option>
    <option class="service-small">Business Services</option>
  </optgroup>
</select>
_x000D_
_x000D_
_x000D_

React - Component Full Screen (with height 100%)

body{
  height:100%
}

#app div{
  height:100%
}

this works for me..

How to get the file path from HTML input form in Firefox 3

This is an example that could work for you if what you need is not exactly the path, but a reference to the file working offline.

http://www.ab-d.fr/date/2008-07-12/

It is in french, but the code is javascript :)

This are the references the article points to: http://developer.mozilla.org/en/nsIDOMFile http://developer.mozilla.org/en/nsIDOMFileList

Find oldest/youngest datetime object in a list

The datetime module has its own versions of min and max as available methods. https://docs.python.org/2/library/datetime.html

Hide Twitter Bootstrap nav collapse on click

$(function() {
    $('.nav a').on('click', function(){ 
        if($('.navbar-toggle').css('display') !='none'){
            $('.navbar-toggle').trigger( "click" );
        }
    });
});

Getting the IP address of the current machine using Java

This could be a bit tricky in the most general case.

On the face of it, InetAddress.getLocalHost() should give you the IP address of this host. The problem is that a host could have lots of network interfaces, and an interface could be bound to more than one IP address. And to top that, not all IP addresses will be reachable outside of your machine or your LAN. For example, they could be IP addresses for virtual network devices, private network IP addresses, and so on.

What this means is that the IP address returned by InetAddress.getLocalHost() might not be the right one to use.

How can you deal with this?

  • One approach is to use NetworkInterface.getNetworkInterfaces() to get all of the known network interfaces on the host, and then iterate over each NI's addresses.
  • Another approach is to (somehow) get the externally advertized FQDN for the host, and use InetAddress.getByName() to look up the primary IP address. (But how do you get it, and how do you deal with a DNS-based load balancer?)
  • A variation of the previous is to get the preferred FQDN from a config file or a command line parameter.
  • Another variation is to get the preferred IP address from a config file or a command line parameter.

In summary, InetAddress.getLocalHost() will typically work, but you may need to provide an alternative method for the cases where your code is run in an environment with "complicated" networking.


I am able to get all the IP addresses associated all Network Interfaces, but how do i distinguish them?

  • Any address in the range 127.xxx.xxx.xxx is a "loopback" address. It is only visible to "this" host.
  • Any address in the range 192.168.xxx.xxx is a private (aka site local) IP address. These are reserved for use within an organization. The same applies to 10.xxx.xxx.xxx addresses, and 172.16.xxx.xxx through 172.31.xxx.xxx.
  • Addresses in the range 169.254.xxx.xxx are link local IP addresses. These are reserved for use on a single network segment.
  • Addresses in the range 224.xxx.xxx.xxx through 239.xxx.xxx.xxx are multicast addresses.
  • The address 255.255.255.255 is the broadcast address.
  • Anything else should be a valid public point-to-point IPv4 address.

In fact, the InetAddress API provides methods for testing for loopback, link local, site local, multicast and broadcast addresses. You can use these to sort out which of the IP addresses you get back is most appropriate.

Send response to all clients except sender

use this coding

io.sockets.on('connection', function (socket) {

    socket.on('mousemove', function (data) {

        socket.broadcast.emit('moving', data);
    });

this socket.broadcast.emit() will emit everthing in the function except to the server which is emitting

Open file dialog box in JavaScript

May use

$('<input type="file" />').click()

nginx: how to create an alias url route?

server {
  server_name example.com;
  root /path/to/root;
  location / {
    # bla bla
  }
  location /demo {
    alias /path/to/root/production/folder/here;
  }
}

If you need to use try_files inside /demo you'll need to replace alias with a root and do a rewrite because of the bug explained here

How to display the current time and date in C#

In WPF you'll need to use the Content property instead:

label1.Content = DateTime.Now.ToString();

How to use timer in C?

You can use a time_t struct and clock() function from time.h.

Store the start time in a time_t struct by using clock() and check the elapsed time by comparing the difference between stored time and current time.

How to get Toolbar from fragment?

You have two choices to get Toolbar in fragment

First one

Toolbar toolbar = (Toolbar) getActivity().findViewById(R.id.toolbar);

and second one

Toolbar toolbar = ((MainActivity) getActivity()).mToolbar;

Laravel Request getting current path with query string

Try to use the following:

\Request::getRequestUri()

What is recursion and when should I use it?

Well, that's a pretty decent definition you have. And wikipedia has a good definition too. So I'll add another (probably worse) definition for you.

When people refer to "recursion", they're usually talking about a function they've written which calls itself repeatedly until it is done with its work. Recursion can be helpful when traversing hierarchies in data structures.

Multiple aggregations of the same column using pandas GroupBy.agg()

You can simply pass the functions as a list:

In [20]: df.groupby("dummy").agg({"returns": [np.mean, np.sum]})
Out[20]:         
           mean       sum
dummy                    
1      0.036901  0.369012

or as a dictionary:

In [21]: df.groupby('dummy').agg({'returns':
                                  {'Mean': np.mean, 'Sum': np.sum}})
Out[21]: 
        returns          
           Mean       Sum
dummy                    
1      0.036901  0.369012

What's the difference between a 302 and a 307 redirect?

Originally there was just 302

Response What browsers should do
302 Found Redo request with new url

The idea is that:

  • if you were doing a GET at some location, you would redo your GET to the new URL
  • if you were doing a POST at some location, you would redo your POST to the new URL
  • if you were doing a PUT at some location, you would redo your PUT to the new URL
  • if you were doing a DELETE at some location, you would redo your DELETE to the new URL
  • etc

Unfortunately every browser did it wrong. When getting a 302, they would always switch to GET at the new URL, rather than retrying the request with the same verb (e.g., POST):

  • Mosaic did it wrong
  • Netscape copied the bugs in Mosaic; so they got it wrong
  • Internet Explorer copied the bugs in Netscape; so they got it wrong

It became de-facto wrong.

All browsers got 302 wrong. So 303 and 307 were created.

Response What browsers should do What browsers actually do
302 Found Redo request with new url GET with new url
303 See Other GET with new url GET with new url
307 Temporary Redirect Redo request with new url Redo request with new url

In chart form

The 5 different kinds of redirects:

+------------------------------------------------------------+
¦           ¦                Switch to GET?                  ¦
¦           ¦------------------------------------------------¦
¦ Temporary ¦          No            ¦         Yes           ¦
¦-----------+------------------------+-----------------------¦
¦ No        ¦ 308 Permanent Redirect ¦ 301 Moved Permanently ¦
¦-----------+------------------------+-----------------------¦
¦ Yes       ¦ 307 Temporary Redirect ¦ 303 See Other         ¦
¦           ¦ 302 Found (intended)   ¦ 302 Found (actual)    ¦
+------------------------------------------------------------+

Alternatively:

Response Switch to get? Temporary?
301 Moved Permanently No No
302 Found (intended) No Yes
302 Found (actual) Yes Yes
303 See Other Yes Yes
307 Temporary Redirect No Yes
308 Permanent Redirect No No

warning: incompatible implicit declaration of built-in function ‘xyz’

In the case of some programs, these errors are normal and should not be fixed.

I get these error messages when compiling the program phrap (for example). This program happens to contain code that modifies or replaces some built in functions, and when I include the appropriate header files to fix the warnings, GCC instead generates a bunch of errors. So fixing the warnings effectively breaks the build.

If you got the source as part of a distribution that should compile normally, the errors might be normal. Consult the documentation to be sure.

Oracle 12c Installation failed to access the temporary location

If your user account has spaces in it and you have tried all the above but none worked,

I recommended you create a new windows user account and give it an administrative privilege, not standard.

Log out of your old account and log into this new account and try installing again. It worked well.

How to view .img files?

.img is way too unspecific. This file extension is widely used for a variety of (raw) file formats. It is an abbreviation for “image” and that can be any image you can imagine—or cannot imagine at all, as you have never heard of it.

For example, .IMG used to be a GEM bitmap image file. Does anyone remember GEM at all? It was the Windows competitor from Digital Research. The Atari ST version was widely used, but there was also a DOS version of GEM. One of the stripped down versions (which was necessary to avoid copyright claims from Apple) was ViewMAX included in DR DOS 3.41, 5.0 and 6.0 as well as Novell DOS 7.0. It is now open source and can be downloaded freely as OpenGEM. Still requires DOS and is included in the FreeDOS distribution. For viewing GEM bitmap images, Windows programs of that time (around DOS-based Windows 3.0) such as Ventura Publisher could open and consequently convert such “GEM images” or “Atari ST images” into other, more widely used formats.

But I doubt that this kind of .img-file is what you meant. Still, you have to be more specific.

Most widely .img is used as a raw filesystem image of e.g. a floppy disk. As mentioned by others, such images can be opened by a number of programs. Or directly mounted under Unix-like systems like BSD and Linux. 7-Zip is also able to extract files from such images for supported filesystems, such as FAT. At least the command-line version. Just type 7z x image.img and it will extract the included files.

Note however that there are also other image formats out there, such as IBM's .dsk, sometimes using different file extensions. Such files can be raw floppy images, but they can also be in IBM's SAVEDSKF/LOADDSKF format. These files are basically raw files with stripped zeros at the end, but with a header at the beginning of the files. I doubt that 7-Zip can extract such images, even though it would only be necessary to find the appropriate offset. Anyhow, since the image past the header is basically raw and uncompressed, using dd you can extract the image and make it a raw .img floppy image. Suppose the header is hex:291 bytes long (which you will have to figure out by looking inside the file e.g. using a hex editor). This equals 657 bytes to skip, resulting in dd if=image.dsk of=rawimage.img bs=1 skip=657. The resulting rawimage.img would however be non-standard in size. This can be fixed, again, by using dd. dd if=/der/zero of=rawimage.img count=0 bs=1 seek=1474560 – this will make a sparse file out of it, resulting in the correct file size for a 1.44 MB floppy image and returning zeros at unused positions. Works with most programs under Linux.

But in general, .img can be any file that is classified as “an image”, thus any application can include a (proprietory) file with this extension. Such files can than only be used (opened) by said application.

How to map a composite key with JPA and Hibernate?

Let's take a simple example. Let's say two tables named test and customer are there described as:

create table test(
  test_id int(11) not null auto_increment,
  primary key(test_id));

create table customer(
  customer_id int(11) not null auto_increment,
  name varchar(50) not null,
  primary key(customer_id));

One more table is there which keeps the track of tests and customer:

create table tests_purchased(
  customer_id int(11) not null,
  test_id int(11) not null,
  created_date datetime not null,
  primary key(customer_id, test_id));

We can see that in the table tests_purchased the primary key is a composite key, so we will use the <composite-id ...>...</composite-id> tag in the hbm.xml mapping file. So the PurchasedTest.hbm.xml will look like:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
  "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
  "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
  <class name="entities.PurchasedTest" table="tests_purchased">

    <composite-id name="purchasedTestId">
      <key-property name="testId" column="TEST_ID" />
      <key-property name="customerId" column="CUSTOMER_ID" />
    </composite-id>

    <property name="purchaseDate" type="timestamp">
      <column name="created_date" />
    </property>

  </class>
</hibernate-mapping>

But it doesn't end here. In Hibernate we use session.load (entityClass, id_type_object) to find and load the entity using primary key. In case of composite keys, the ID object should be a separate ID class (in above case a PurchasedTestId class) which just declares the primary key attributes like below:

import java.io.Serializable;

public class PurchasedTestId implements Serializable {
  private Long testId;
  private Long customerId;

  // an easy initializing constructor
  public PurchasedTestId(Long testId, Long customerId) {
    this.testId = testId;
    this.customerId = customerId;
  }

  public Long getTestId() {
    return testId;
  }

  public void setTestId(Long testId) {
    this.testId = testId;
  }

  public Long getCustomerId() {
    return customerId;
  }

  public void setCustomerId(Long customerId) {
    this.customerId = customerId;
  }

  @Override
  public boolean equals(Object arg0) {
    if(arg0 == null) return false;
    if(!(arg0 instanceof PurchasedTestId)) return false;
    PurchasedTestId arg1 = (PurchasedTestId) arg0;
    return (this.testId.longValue() == arg1.getTestId().longValue()) &&
           (this.customerId.longValue() == arg1.getCustomerId().longValue());
  }

  @Override
  public int hashCode() {
    int hsCode;
    hsCode = testId.hashCode();
    hsCode = 19 * hsCode+ customerId.hashCode();
    return hsCode;
  }
}

Important point is that we also implement the two functions hashCode() and equals() as Hibernate relies on them.

How to check if bootstrap modal is open, so I can use jquery validate?

As a workaround I personally use a custom global flag to determine whether the modal has been opened or not and I reset it on 'hidden.bs.modal'

How do you delete a column by name in data.table?

You can also use set for this, which avoids the overhead of [.data.table in loops:

dt <- data.table( a=letters, b=LETTERS, c=seq(26), d=letters, e=letters )
set( dt, j=c(1L,3L,5L), value=NULL )
> dt[1:5]
   b d
1: A a
2: B b
3: C c
4: D d
5: E e

If you want to do it by column name, which(colnames(dt) %in% c("a","c","e")) should work for j.

how to instanceof List<MyType>?

if(!myList.isEmpty() && myList.get(0) instanceof MyType){
    // MyType object
}

In Linux, how to tell how much memory processes are using?

The tool you want is ps. To get information about what java programs are doing:

ps -F -C java 

To get information about http:

ps -F -C httpd

If your program is ending before you get a chance to run these, open another terminal and run:

while true; do ps -F -C myCoolCode ; sleep 0.5s ; done

Make an image width 100% of parent div, but not bigger than its own width

In line style - this works for me every time

<div class="imgWrapper">
    <img src="/theImg.jpg" style="max-width: 100%">
</div>

How to increase the distance between table columns in HTML?

There isn't any need for fake <td>s. Make use of border-spacing instead. Apply it like this:

HTML:

<table>
  <tr>
    <td>First Column</td>
    <td>Second Column</td>
    <td>Third Column</td>
  </tr>
</table>

CSS:

table {
  border-collapse: separate;
  border-spacing: 50px 0;
}

td {
  padding: 10px 0;
}

See it in action.

serialize/deserialize java 8 java.time with Jackson JSON mapper

all you need to know is in Jackson Documentation https://www.baeldung.com/jackson-serialize-dates

Ad.9 quick solved the problem for me.

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JavaTimeModule());
mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);

List All Google Map Marker Images

var pinIcon = new google.maps.MarkerImage(
    "http://chart.apis.google.com/chart?chst=d_map_pin_letter&chld=%E2%80%A2|00D900",
    null, /* size is determined at runtime */
    null, /* origin is 0,0 */
    null, /* anchor is bottom center of the scaled image */
    new google.maps.Size(12, 18)
);

Get the current fragment object

Now at some point of time I need to identify which object is currently there

Call findFragmentById() on FragmentManager and determine which fragment is in your R.id.frameTitle container.

If you are using the androidx edition of Fragment — as you should in modern apps — , use getSupportFragmentManager() on your FragmentActivity/AppCompatActivity instead of getFragmentManager()

Count textarea characters

_x000D_
_x000D_
var maxchar = 10;_x000D_
$('#message').after('<span id="count" class="counter"></span>');_x000D_
$('#count').html(maxchar+' of '+maxchar);_x000D_
$('#message').attr('maxlength', maxchar);_x000D_
$('#message').parent().addClass('wrap-text');_x000D_
$('#message').on("keydown", function(e){_x000D_
 var len =  $('#message').val().length;_x000D_
 if (len >= maxchar && e.keyCode != 8)_x000D_
     e.preventDefault();_x000D_
 else if(len <= maxchar && e.keyCode == 8){_x000D_
  if(len <= maxchar && len != 0)_x000D_
      $('#count').html(maxchar+' of '+(maxchar - len +1));_x000D_
     else if(len == 0)_x000D_
      $('#count').html(maxchar+' of '+(maxchar - len));_x000D_
 }else_x000D_
   $('#count').html(maxchar+' of '+(maxchar - len-1)); _x000D_
})
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<textarea id="message" name="text"></textarea>
_x000D_
_x000D_
_x000D_

Eclipse copy/paste entire line keyboard shortcut

The combination of Ctrl + Shift + Alt + Down worked for me on Linux.

Pressed <button> selector

You could use :focus which will remain the style as long as the user doesn't click elsewhere.

button:active {
    border: 2px solid green;
}

button:focus {
    border: 2px solid red;
}

How to fix: "No suitable driver found for jdbc:mysql://localhost/dbname" error when using pools?

From other stackoverflow thread:

"Second. Make sure that you have MySQL JDBC Driver aka Connector/J in JMeter's classpath. If you don't - download it, unpack and drop mysql-connector-java-x.xx.xx-bin.jar to JMeter's /lib folder. JMeter restart will be required to pick the library up"

Please be sure that .jar file is added directly to the lib folder.

JS file gets a net::ERR_ABORTED 404 (Not Found)

As mentionned in comments: you need a way to send your static files to the client. This can be achieved with a reverse proxy like Nginx, or simply using express.static().

Put all your "static" (css, js, images) files in a folder dedicated to it, different from where you put your "views" (html files in your case). I'll call it static for the example. Once it's done, add this line in your server code:

app.use("/static", express.static('./static/'));

This will effectively serve every file in your "static" folder via the /static route.

Querying your index.js file in the client thus becomes:

<script src="static/index.js"></script>

Total memory used by Python process?

Below is my function decorator which allows to track how much memory this process consumed before the function call, how much memory it uses after the function call, and how long the function is executed.

import time
import os
import psutil


def elapsed_since(start):
    return time.strftime("%H:%M:%S", time.gmtime(time.time() - start))


def get_process_memory():
    process = psutil.Process(os.getpid())
    return process.memory_info().rss


def track(func):
    def wrapper(*args, **kwargs):
        mem_before = get_process_memory()
        start = time.time()
        result = func(*args, **kwargs)
        elapsed_time = elapsed_since(start)
        mem_after = get_process_memory()
        print("{}: memory before: {:,}, after: {:,}, consumed: {:,}; exec time: {}".format(
            func.__name__,
            mem_before, mem_after, mem_after - mem_before,
            elapsed_time))
        return result
    return wrapper

So, when you have some function decorated with it

from utils import track

@track
def list_create(n):
    print("inside list create")
    return [1] * n

You will be able to see this output:

inside list create
list_create: memory before: 45,928,448, after: 46,211,072, consumed: 282,624; exec time: 00:00:00

How to handle authentication popup with Selenium WebDriver using Java

Popular solution is to append username and password in URL, like, http://username:[email protected]. However, if your username or password contains special character, then it may fail. So when you create the URL, make sure you encode those special characters.

String username = URLEncoder.encode(user, StandardCharsets.UTF_8.toString());
String password = URLEncoder.encode(pass, StandardCharsets.UTF_8.toString());
String url = “http://“ + username + “:” + password + “@website.com”;
driver.get(url);

How to set a cookie for another domain

Send a POST request from A. Post requests are on the serverside only and can't be accessed by the client.

You can send a POST request from a.com to b.com using CURL (recommended, serverside) or a hidden method="POST" form (clientside). If you go for the latter, you might want to obfuscate your JavaScript so that the user won't be able to understand the algorithm and interfere with it.

Make a gateway on b.com to set cookies:

<?php
    if (isset($_POST['data']) {
        setcookie('a', $_POST['data']);
        header("Location: b.com/landingpage");
    }
?>

If you want to bring security a step further, implement a function on both sides (a.com and b.com) to encrypt (on a.com) and decrypt (on b.com) data using a cryptographic cypher.

If you're trying to do something that must be absolutely secure (e.g. transfer a login session) try oAuth or take some inspiration from https://api.cloudianos.com/docs#v2/auth

Java abstract interface

It's not necessary, it's optional, just as public on interface methods.

See the JLS on this:

http://java.sun.com/docs/books/jls/second_edition/html/interfaces.doc.html

9.1.1.1 abstract Interfaces Every interface is implicitly abstract. This modifier is obsolete and should not be used in new programs.

And

9.4 Abstract Method Declarations

[...]

For compatibility with older versions of the Java platform, it is permitted but discouraged, as a matter of style, to redundantly specify the abstract modifier for methods declared in interfaces.

It is permitted, but strongly discouraged as a matter of style, to redundantly specify the public modifier for interface methods.

Rounding Bigdecimal values with 2 Decimal Places

I think that the RoundingMode you are looking for is ROUND_HALF_EVEN. From the javadoc:

Rounding mode to round towards the "nearest neighbor" unless both neighbors are equidistant, in which case, round towards the even neighbor. Behaves as for ROUND_HALF_UP if the digit to the left of the discarded fraction is odd; behaves as for ROUND_HALF_DOWN if it's even. Note that this is the rounding mode that minimizes cumulative error when applied repeatedly over a sequence of calculations.

Here is a quick test case:

BigDecimal a = new BigDecimal("10.12345");
BigDecimal b = new BigDecimal("10.12556");

a = a.setScale(2, BigDecimal.ROUND_HALF_EVEN);
b = b.setScale(2, BigDecimal.ROUND_HALF_EVEN);

System.out.println(a);
System.out.println(b);

Correctly prints:

10.12
10.13

UPDATE:

setScale(int, int) has not been recommended since Java 1.5, when enums were first introduced, and was finally deprecated in Java 9. You should now use setScale(int, RoundingMode) e.g:

setScale(2, RoundingMode.HALF_EVEN)

Programmatically change input type of the EditText from PASSWORD to NORMAL & vice versa

Another simple example using ImageView to toggle visibility with less code, because of single InputType assign we need only equality operator:

EditText inputPassword = (EditText) findViewById(R.id.loginPassword);
ImageView inputPasswordShow = (ImageView) findViewById(R.id.imagePasswordShow);
inputPasswordShow.setOnClickListener(new View.OnClickListener() {
     @Override
     public void onClick(View view) {
         if(inputPassword.getInputType() == InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD) {
              inputPassword.setInputType( InputType.TYPE_CLASS_TEXT |
                                        InputType.TYPE_TEXT_VARIATION_PASSWORD);
         }else {
              inputPassword.setInputType( InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD );
         }
         inputPassword.setSelection(inputPassword.getText().length());
    }
});

Replacing :

InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD

With :

InputType.TYPE_CLASS_TEXT

Will give the same result but shorter word.

How to strip HTML tags from string in JavaScript?

var html = "<p>Hello, <b>World</b>";
var div = document.createElement("div");
div.innerHTML = html;
alert(div.innerText); // Hello, World

That pretty much the best way of doing it, you're letting the browser do what it does best -- parse HTML.


Edit: As noted in the comments below, this is not the most cross-browser solution. The most cross-browser solution would be to recursively go through all the children of the element and concatenate all text nodes that you find. However, if you're using jQuery, it already does it for you:

alert($("<p>Hello, <b>World</b></p>").text());

Check out the text method.

Spark java.lang.OutOfMemoryError: Java heap space

You should configure offHeap memory settings as shown below:

val spark = SparkSession
     .builder()
     .master("local[*]")
     .config("spark.executor.memory", "70g")
     .config("spark.driver.memory", "50g")
     .config("spark.memory.offHeap.enabled",true)
     .config("spark.memory.offHeap.size","16g")   
     .appName("sampleCodeForReference")
     .getOrCreate()

Give the driver memory and executor memory as per your machines RAM availability. You can increase the offHeap size if you are still facing the OutofMemory issue.

changing source on html5 video tag

I hated all these answers because they were too short or relied on other frameworks.

Here is "one" vanilla JS way of doing this, working in Chrome, please test in other browsers:

http://jsfiddle.net/mattdlockyer/5eCEu/2/

HTML:

<video id="video" width="320" height="240"></video>

JS:

var video = document.getElementById('video');
var source = document.createElement('source');

source.setAttribute('src', 'http://www.tools4movies.com/trailers/1012/Kill%20Bill%20Vol.3.mp4');

video.appendChild(source);
video.play();

setTimeout(function() {  
    video.pause();

    source.setAttribute('src', 'http://www.tools4movies.com/trailers/1012/Despicable%20Me%202.mp4'); 

    video.load();
    video.play();
}, 3000);

Cannot open include file 'afxres.h' in VC2010 Express

Even I too faced similar issue,

fatal error RC1015: cannot open include file 'afxres.h'. from this code

Replacing afxres.h with Winresrc.h and declaring IDC_STATIC as -1 worked for me. (Using visual studio Premium 2012)

//#include "afxres.h"
#include "WinResrc.h"
#define IDC_STATIC  -1

Creating and writing lines to a file

' Create The Object
Set FSO = CreateObject("Scripting.FileSystemObject")

' How To Write To A File
Set File = FSO.CreateTextFile("C:\foo\bar.txt",True)
File.Write "Example String"
File.Close

' How To Read From A File
Set File = FSO.OpenTextFile("C:\foo\bar.txt")
Do Until File.AtEndOfStream
    Line = File.ReadLine
    WScript.Echo(Line)
Loop
File.Close

' Another Method For Reading From A File
Set File = FSO.OpenTextFile("C:\foo\bar.txt")
Set Text = File.ReadAll
WScript.Echo(Text)
File.Close

Angular - ui-router get previous state

For UI-Router(>=1.0), StateChange events have been deprecated. For complete migration guide, click here

To get the previous state of the current state in UI-Router 1.0+:

app.run(function ($transitions) {
    $transitions.onSuccess({}, function (trans) {
         // previous state and paramaters
         var previousState = trans.from().name;
         var previousStateParameters = trans.params('from');
    });
});

How do you access the matched groups in a JavaScript regular expression?

You can access capturing groups like this:

_x000D_
_x000D_
var myString = "something format_abc";_x000D_
var myRegexp = /(?:^|\s)format_(.*?)(?:\s|$)/g;_x000D_
var match = myRegexp.exec(myString);_x000D_
console.log(match[1]); // abc
_x000D_
_x000D_
_x000D_

And if there are multiple matches you can iterate over them:

_x000D_
_x000D_
var myString = "something format_abc";_x000D_
var myRegexp = /(?:^|\s)format_(.*?)(?:\s|$)/g;_x000D_
match = myRegexp.exec(myString);_x000D_
while (match != null) {_x000D_
  // matched text: match[0]_x000D_
  // match start: match.index_x000D_
  // capturing group n: match[n]_x000D_
  console.log(match[0])_x000D_
  match = myRegexp.exec(myString);_x000D_
}
_x000D_
_x000D_
_x000D_

Edit: 2019-09-10

As you can see the way to iterate over multiple matches was not very intuitive. This lead to the proposal of the String.prototype.matchAll method. This new method is expected to ship in the ECMAScript 2020 specification. It gives us a clean API and solves multiple problems. It has been started to land on major browsers and JS engines as Chrome 73+ / Node 12+ and Firefox 67+.

The method returns an iterator and is used as follows:

_x000D_
_x000D_
const string = "something format_abc";_x000D_
const regexp = /(?:^|\s)format_(.*?)(?:\s|$)/g;_x000D_
const matches = string.matchAll(regexp);_x000D_
    _x000D_
for (const match of matches) {_x000D_
  console.log(match);_x000D_
  console.log(match.index)_x000D_
}
_x000D_
_x000D_
_x000D_

As it returns an iterator, we can say it's lazy, this is useful when handling particularly large numbers of capturing groups, or very large strings. But if you need, the result can be easily transformed into an Array by using the spread syntax or the Array.from method:

function getFirstGroup(regexp, str) {
  const array = [...str.matchAll(regexp)];
  return array.map(m => m[1]);
}

// or:
function getFirstGroup(regexp, str) {
  return Array.from(str.matchAll(regexp), m => m[1]);
}

In the meantime, while this proposal gets more wide support, you can use the official shim package.

Also, the internal workings of the method are simple. An equivalent implementation using a generator function would be as follows:

function* matchAll(str, regexp) {
  const flags = regexp.global ? regexp.flags : regexp.flags + "g";
  const re = new RegExp(regexp, flags);
  let match;
  while (match = re.exec(str)) {
    yield match;
  }
}

A copy of the original regexp is created; this is to avoid side-effects due to the mutation of the lastIndex property when going through the multple matches.

Also, we need to ensure the regexp has the global flag to avoid an infinite loop.

I'm also happy to see that even this StackOverflow question was referenced in the discussions of the proposal.

How do I read and parse an XML file in C#?

XmlDocument to read an XML from string or from file.

XmlDocument doc = new XmlDocument();
doc.Load("c:\\temp.xml");

or

doc.LoadXml("<xml>something</xml>");

then find a node below it ie like this

XmlNode node = doc.DocumentElement.SelectSingleNode("/book/title");

or

foreach(XmlNode node in doc.DocumentElement.ChildNodes){
   string text = node.InnerText; //or loop through its children as well
}

then read the text inside that node like this

string text = node.InnerText;

or read an attribute

string attr = node.Attributes["theattributename"]?.InnerText

Always check for null on Attributes["something"] since it will be null if the attribute does not exist.

How do you read CSS rule values with JavaScript?

SOLUTION 1 (CROSS-BROWSER)

function GetProperty(classOrId,property)
{ 
    var FirstChar = classOrId.charAt(0);  var Remaining= classOrId.substring(1);
    var elem = (FirstChar =='#') ?  document.getElementById(Remaining) : document.getElementsByClassName(Remaining)[0];
    return window.getComputedStyle(elem,null).getPropertyValue(property);
}

alert( GetProperty(".my_site_title","position") ) ;

SOLUTION 2 (CROSS-BROWSER)

function GetStyle(CLASSname) 
{
    var styleSheets = document.styleSheets;
    var styleSheetsLength = styleSheets.length;
    for(var i = 0; i < styleSheetsLength; i++){
        if (styleSheets[i].rules ) { var classes = styleSheets[i].rules; }
        else { 
            try {  if(!styleSheets[i].cssRules) {continue;} } 
            //Note that SecurityError exception is specific to Firefox.
            catch(e) { if(e.name == 'SecurityError') { console.log("SecurityError. Cant readd: "+ styleSheets[i].href);  continue; }}
            var classes = styleSheets[i].cssRules ;
        }
        for (var x = 0; x < classes.length; x++) {
            if (classes[x].selectorText == CLASSname) {
                var ret = (classes[x].cssText) ? classes[x].cssText : classes[x].style.cssText ;
                if(ret.indexOf(classes[x].selectorText) == -1){ret = classes[x].selectorText + "{" + ret + "}";}
                return ret;
            }
        }
    }
}

alert( GetStyle('.my_site_title') );

Combining INSERT INTO and WITH/CTE

Yep:

WITH tab (
  bla bla
)

INSERT INTO dbo.prf_BatchItemAdditionalAPartyNos (  BatchID,                                                        AccountNo,
APartyNo,
SourceRowID)    

SELECT * FROM tab

Note that this is for SQL Server, which supports multiple CTEs:

WITH x AS (), y AS () INSERT INTO z (a, b, c) SELECT a, b, c FROM y

Teradata allows only one CTE and the syntax is as your example.

How can I simulate mobile devices and debug in Firefox Browser?

You can use tools own browser (Firefox, IE, Chrome...) to debug your JavaScript.

As for resizing, Firefox/Chrome has own resources accessible via Ctrl + Shift + I OR F12. Going tab "style editor" and clicking "adaptive/responsive design" icon.

Old Firefox versions

Old Firefox

New Firefox/Firebug

Firefox

Chrome

Chrome

*Another way is to install an addon like "Web Developer"

use mysql SUM() in a WHERE clause

When using aggregate functions to filter, you must use a HAVING statement.

SELECT *
FROM tblMoney
HAVING Sum(CASH) > 500

Cast Int to enum in Java

Use MyEnum enumValue = MyEnum.values()[x];

Center Align on a Absolutely Positioned Div

I was having the same issue, and my limitation was that i cannot have a predefined width. If your element does not have a fixed width, then try this

div#thing 
{ 
  position: absolute; 
  top: 0px; 
  z-index: 2; 
  left:0;
  right:0;
 }

div#thing-body
{
  text-align:center;
}

then modify your html to look like this

<div id="thing">
 <div id="thing-child">
  <p>text text text with no fixed size, variable font</p>
 </div>
</div>

Run a Java Application as a Service on Linux

I wrote another simple wrapper here:

#!/bin/sh
SERVICE_NAME=MyService
PATH_TO_JAR=/usr/local/MyProject/MyJar.jar
PID_PATH_NAME=/tmp/MyService-pid
case $1 in
    start)
        echo "Starting $SERVICE_NAME ..."
        if [ ! -f $PID_PATH_NAME ]; then
            nohup java -jar $PATH_TO_JAR /tmp 2>> /dev/null >> /dev/null &
            echo $! > $PID_PATH_NAME
            echo "$SERVICE_NAME started ..."
        else
            echo "$SERVICE_NAME is already running ..."
        fi
    ;;
    stop)
        if [ -f $PID_PATH_NAME ]; then
            PID=$(cat $PID_PATH_NAME);
            echo "$SERVICE_NAME stoping ..."
            kill $PID;
            echo "$SERVICE_NAME stopped ..."
            rm $PID_PATH_NAME
        else
            echo "$SERVICE_NAME is not running ..."
        fi
    ;;
    restart)
        if [ -f $PID_PATH_NAME ]; then
            PID=$(cat $PID_PATH_NAME);
            echo "$SERVICE_NAME stopping ...";
            kill $PID;
            echo "$SERVICE_NAME stopped ...";
            rm $PID_PATH_NAME
            echo "$SERVICE_NAME starting ..."
            nohup java -jar $PATH_TO_JAR /tmp 2>> /dev/null >> /dev/null &
            echo $! > $PID_PATH_NAME
            echo "$SERVICE_NAME started ..."
        else
            echo "$SERVICE_NAME is not running ..."
        fi
    ;;
esac 

You can follow a full tutorial for init.d here and for systemd (ubuntu 16+) here

If you need the output log replace the 2

nohup java -jar $PATH_TO_JAR /tmp 2>> /dev/null >> /dev/null &

lines for

nohup java -jar $PATH_TO_JAR >> myService.out 2>&1&

Generating statistics from Git repository

Just yesterday I've added my git-analytics docker-compose file, which builds up several containers to start analyzing multiple git repositories against each other.

It is able to show you commit statistics over time about the author and also several diff statistics.

You can use the provided angular client and also kibana to visualize the statistics.

https://github.com/alexejsailer/git-analytics-docker

It will be improved over time.

Angular Client Screenshot

Angular Client Screenshot

Kibana Client Screenshot

Kibana Client Screenshot]

git pull displays "fatal: Couldn't find remote ref refs/heads/xxxx" and hangs up

I just ran into a similar issue when I tried to commit to a newly created repo with a "." in it's name. I've seen several others have different issues with putting a "." in the repo name.

I just re-created the repo and

replaced "." with "-"

There may be other ways to resolve this, but this was a quick fix for me since it was a new repo.

Read specific columns with pandas or other python module

An easy way to do this is using the pandas library like this.

import pandas as pd
fields = ['star_name', 'ra']

df = pd.read_csv('data.csv', skipinitialspace=True, usecols=fields)
# See the keys
print df.keys()
# See content in 'star_name'
print df.star_name

The problem here was the skipinitialspace which remove the spaces in the header. So ' star_name' becomes 'star_name'

Better solution without exluding fields from Binding

You should not use your domain models in your views. ViewModels are the correct way to do it.

You need to map your domain model's necessary fields to viewmodel and then use this viewmodel in your controllers. This way you will have the necessery abstraction in your application.

If you never heard of viewmodels, take a look at this.

How to delete Tkinter widgets from a window?

I found that when the widget is part of a function and the grid_remove is part of another function it does not remove the label. In this example...

def somefunction(self):
    Label(self, text=" ").grid(row = 0, column = 0)
    self.text_ent = Entry(self)
    self.text_ent.grid(row = 1, column = 0)
def someotherfunction(self):
    somefunction.text_ent.grid_remove()

...there is no valid way of removing the Label.

The only solution I could find is to give the label a name and make it global:

def somefunction(self):
    global label
    label = Label(self, text=" ")
    label.grid(row = 0, column = 0)
    self.text_ent = Entry(self)
    self.text_ent.grid(row = 1, column = 0)
def someotherfunction(self):
    global label
    somefunction.text_ent.grid_remove()
    label.grid_remove()

When I ran into this problem there was a class involved, one function being in the class and one not, so I'm not sure the global label lines are really needed in the above.

Hashcode and Equals for Hashset

You should read up on how to ensure that you've implemented equals and hashCode properly. This is a good starting point: What issues should be considered when overriding equals and hashCode in Java?

How to select different app.config for several build configurations

See if the XDT (web.config) transform engine can help you. Currently it's only natively supported for web projects, but technically there is nothing stopping you from using it in other application types. There are many guides on how to use XDT by manually editing the project files, but I found a plugin that works great: https://visualstudiogallery.msdn.microsoft.com/579d3a78-3bdd-497c-bc21-aa6e6abbc859

The plugin is only helping to setup the configuration, it's not needed to build and the solution can be built on other machines or on a build server without the plugin or any other tools being required.

Excel formula is only showing the formula rather than the value within the cell in Office 2010

Check the formatting (right click on cell, Format Cells). Under tab "Number" the category should be "General". If, for instance, it's "Text" anything typed in would be treated as a string rather than a formula to be interpreted.

Cannot create a connection to data source Error (rsErrorOpeningConnection) in SSRS

I had the same issue "Cannot create a connection to data source...Login failed for user.." on Windows 8.1, SQL Server 2014 Developer Edition and Visual Studio 2013 Pro. All solutions offered above by other Stackoverflow Community members did not work for me.

So, I did the next steps (running all Windows applications as Administrator):

  1. VS2013 SSRS: I converted my Data Source to Shared Data Source (.rds) with Windows Authentication (Integrated Security) on the Right Pane "Solution Explorer".

  2. Original (non-shared) Data Source (on the Left Pane "Report Data") got "Don't Use Credentials".

  3. On the Project Properties, I set for "Deployment" "Overwrite DataSources" to "True" and redeployed the Project.

enter image description here

After that, I could run my report without further requirements to enter Credentials. All Shared DataSources were deployed in a separate Directory "DataSources".

enter image description here

enter image description here

Hash function for a string

Use boost::hash

#include <boost\functional\hash.hpp>

...

std::string a = "ABCDE";
size_t b = boost::hash_value(a);

Access a function variable outside the function without using "global"

The problem is you were calling print x.bye after you set x as a string. When you run x = hi() it runs hi() and sets the value of x to 5 (the value of bye; it does NOT set the value of x as a reference to the bye variable itself). EX: bye = 5; x = bye; bye = 4; print x; prints 5, not 4

Also, you don't have to run hi() twice, just run x = hi(), not hi();x=hi() (the way you had it it was running hi(), not doing anything with the resulting value of 5, and then rerunning the same hi() and saving the value of 5 to the x variable.

So full code should be

def hi():
    something
    something
    bye = 5
    return bye 
x = hi()
print x

If you wanted to return multiple variables, one option would be to use a list, or dictionary, depending on what you need.

ex:

def hi():
    something
    xyz = { 'bye': 7, 'foobar': 8}
    return xyz
x = hi()
print x['bye']

more on python dictionaries at http://docs.python.org/2/tutorial/datastructures.html#dictionaries

Passing parameters to click() & bind() event in jquery?

var someParam = xxxxxxx;

commentbtn.click(function(){

    alert(someParam );
});

Detecting negative numbers

Don't get me wrong, but you can do this way ;)

function nagitive_check($value){
if (isset($value)){
    if (substr(strval($value), 0, 1) == "-"){
    return 'It is negative<br>';
} else {
    return 'It is not negative!<br>';
}
    }
}

Output:

echo nagitive_check(-100);  // It is negative
echo nagitive_check(200);  // It is not negative!
echo nagitive_check(200-300);  // It is negative
echo nagitive_check(200-300+1000);  // It is not negative!

Rails 3 execute custom sql query without a model

Maybe try this:

ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)

how to destroy an object in java?

Answer E is correct answer. If E is not there, you will soon run out of memory (or) No correct answer.

Object should be unreachable to be eligible for GC. JVM will do multiple scans and moving objects from one generation to another generation to determine the eligibility of GC and frees the memory when the objects are not reachable.

What is a "callable"?

A callable is an object allows you to use round parenthesis ( ) and eventually pass some parameters, just like functions.

Every time you define a function python creates a callable object. In example, you could define the function func in these ways (it's the same):

class a(object):
    def __call__(self, *args):
        print 'Hello'

func = a()

# or ... 
def func(*args):
    print 'Hello'

You could use this method instead of methods like doit or run, I think it's just more clear to see obj() than obj.doit()

How can I convert a Timestamp into either Date or DateTime object?

java.time

Modern answer: use java.time, the modern Java date and time API, for your date and time work. Back in 2011 it was right to use the Timestamp class, but since JDBC 4.2 it is no longer advised.

For your work we need a time zone and a couple of formatters. We may as well declare them static:

static ZoneId zone = ZoneId.of("America/Marigot");
static DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern("MM/dd/uuuu");
static DateTimeFormatter timeFormatter = DateTimeFormatter.ofPattern("HH:mm xx");

Now the code could be for example:

    while(resultSet.next()) {
        ZonedDateTime dtStart = resultSet.getObject("dtStart", OffsetDateTime.class)
                 .atZoneSameInstant(zone);

        // I would like to then have the date and time
        // converted into the formats mentioned...
        String dateFormatted = dtStart.format(dateFormatter);
        String timeFormatted = dtStart.format(timeFormatter);
        System.out.format("Date: %s; time: %s%n", dateFormatted, timeFormatted);
    }

Example output (using the time your question was asked):

Date: 09/20/2011; time: 18:13 -0400

In your database timestamp with time zone is recommended for timestamps. If this is what you’ve got, retrieve an OffsetDateTime as I am doing in the code. I am also converting the retrieved value to the user’s time zone before formatting date and time separately. As time zone I supplied America/Marigot as an example, please supply your own. You may also leave out the time zone conversion if you don’t want any, of course.

If the datatype in SQL is a mere timestamp without time zone, retrieve a LocalDateTime instead. For example:

        ZonedDateTime dtStart = resultSet.getObject("dtStart", LocalDateTime.class)
                 .atZone(zone);

No matter the details I trust you to do similarly for dtEnd.

I wasn’t sure what you meant by the xx in HH:MM xx. I just left it in the format pattern string, which yields the UTC offset in hours and minutes without colon.

Link: Oracle tutorial: Date Time explaining how to use java.time.

How to install the Six module in Python2.7

here's what six is:

pip search six
six                       - Python 2 and 3 compatibility utilities

to install:

pip install six

though if you did install python-dateutil from pip six should have been set as a dependency.

N.B.: to install pip run easy_install pip from command line.

Change WPF controls from a non-main thread using Dispatcher.Invoke

When a thread is executing and you want to execute the main UI thread which is blocked by current thread, then use the below:

current thread:

Dispatcher.CurrentDispatcher.Invoke(MethodName,
    new object[] { parameter1, parameter2 }); // if passing 2 parameters to method.

Main UI thread:

Application.Current.Dispatcher.BeginInvoke(
    DispatcherPriority.Background, new Action(() => MethodName(parameter)));

Why does CSS not support negative padding?

Because the designers of CSS didn't have the foresight to imagine the flexibility this would bring. There are plenty of reasons to expand the content area of a box without affecting its relationship to neighbouring elements. If you think it's not possible, put some long nowrap'd text in a box, set a width on the box, and watch how the overflowed content does nothing to the layout.

Yes, this is still relevant with CSS3 in 2019; case in point: flexbox layouts. Flexbox items' margins do not collapse, so in order to space them evenly and align them with the visual edge of the container, one must subtract the items' margins from their container's padding. If any result is < 0, you must use a negative margin on the container, or sum that negative with the existing margin. I.e. the content of the element effects how one defines the margins for it, which is backwards. Summing doesn't work cleanly when flex elements' content have margins defined in different units or are affected by a different font-size, etc.

The example below should, ideally have aligned and evenly spaced grey boxes but, sadly they aren't.

_x000D_
_x000D_
body {_x000D_
  font-family: sans-serif;_x000D_
  margin: 2rem;_x000D_
}_x000D_
body > * {_x000D_
  margin: 2rem 0 0;_x000D_
}_x000D_
body > :first-child {_x000D_
  margin-top: 0;_x000D_
}_x000D_
h1,_x000D_
li,_x000D_
p {_x000D_
  padding: 10px;_x000D_
  background: lightgray;_x000D_
}_x000D_
ul {_x000D_
  list-style: none;_x000D_
  display: flex;_x000D_
  flex-wrap: wrap;_x000D_
  padding: 0;/* just to reset */_x000D_
  padding: -5px;/* would allow correct alignment */_x000D_
}_x000D_
li {_x000D_
  flex: 1 1 auto;_x000D_
  margin: 5px;_x000D_
}
_x000D_
<h1>Cras facilisis orci ligula</h1>_x000D_
_x000D_
<ul>_x000D_
  <li>a lacinia purus porttitor eget</li>_x000D_
  <li>donec ut nunc lorem</li>_x000D_
  <li>duis in est dictum</li>_x000D_
  <li>tempor metus non</li>_x000D_
  <li>dapibus sapien</li>_x000D_
  <li>phasellus bibendum tincidunt</li>_x000D_
  <li>quam vitae accumsan</li>_x000D_
  <li>ut interdum eget nisl in eleifend</li>_x000D_
  <li>maecenas sodales interdum quam sed accumsan</li>_x000D_
</ul>_x000D_
_x000D_
<p>Fusce convallis, arcu vel elementum pulvinar, diam arcu tempus dolor, nec venenatis sapien diam non dui. Nulla mollis velit dapibus magna pellentesque, at tempor sapien blandit. Sed consectetur nec orci ac lobortis.</p>_x000D_
_x000D_
<p>Integer nibh purus, convallis eget tincidunt id, eleifend id lectus. Vivamus tristique orci finibus, feugiat eros id, semper augue.</p>
_x000D_
_x000D_
_x000D_

I have encountered enough of these little issues over the years where a little negative padding would have gone a long way, but instead I'm forced to add non-semantic markup, use calc(), or CSS preprocessors which only work when the units are the same, etc.

Setting default checkbox value in Objective-C?

Documentation on UISwitch says:

[mySwitch setOn:NO]; 

In Interface Builder, select your switch and in the Attributes inspector you'll find State which can be set to on or off.

importing go files in same folder

./main.go (in package main)
./a/a.go (in package a)
./a/b.go (in package a)

in this case:
main.go import "./a"

It can call the function in the a.go and b.go,that with first letter caps on.

Fixing the order of facets in ggplot

There are a couple of good solutions here.

Similar to the answer from Harpal, but within the facet, so doesn't require any change to underlying data or pre-plotting manipulation:

# Change this code:
facet_grid(.~size) + 
# To this code:
facet_grid(~factor(size, levels=c('50%','100%','150%','200%')))

This is flexible, and can be implemented for any variable as you change what element is faceted, no underlying change in the data required.

Checkbox angular material checked by default

this works for me in Angular 7

// in component.ts
checked: boolean = true;

changeValue(value) {
    this.checked = !value;
}

// in component.html
<mat-checkbox value="checked" (click)="changeValue(checked)" color="primary">
   some Label
</mat-checkbox>

I hope help someone ... greetings. let me know if someone have some easiest

How can I disable ARC for a single file in a project?

Just use the -fno-objc-arc flag in Build Phases>Compile Sources

How to convert JSON to a Ruby hash

Assuming you have a JSON hash hanging around somewhere, to automatically convert it into something like WarHog's version, wrap your JSON hash contents in %q{hsh} tags.

This seems to automatically add all the necessary escaped text like in WarHog's answer.

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

The only thing missing hidden from Rob W's excellent answer is how to communicate between the injected page script and the content script.

On the receiving side (either your content script or the injected page script) add an event listener:

document.addEventListener('yourCustomEvent', function (e) {
  var data = e.detail;
  console.log('received', data);
});

On the initiator side (content script or injected page script) send the event:

var data = {
  allowedTypes: 'those supported by structured cloning, see the list below',
  inShort: 'no DOM elements or classes/functions',
};

document.dispatchEvent(new CustomEvent('yourCustomEvent', { detail: data }));

Notes:

  • DOM messaging uses structured cloning algorithm, which can transfer only some types of data in addition to primitive values. It can't send class instances or functions or DOM elements.
  • In Firefox, to send an object (i.e. not a primitive value) from the content script to the page context you have to explicitly clone it into the target using cloneInto (a built-in function), otherwise it'll fail with a security violation error.

    document.dispatchEvent(new CustomEvent('yourCustomEvent', {
      detail: cloneInto(data, document.defaultView),
    }));
    

jquery.ajax Access-Control-Allow-Origin

http://encosia.com/using-cors-to-access-asp-net-services-across-domains/

refer the above link for more details on Cross domain resource sharing.

you can try using JSONP . If the API is not supporting jsonp, you have to create a service which acts as a middleman between the API and your client. In my case, i have created a asmx service.

sample below:

ajax call:

$(document).ready(function () {
        $.ajax({
            crossDomain: true,
            type:"GET",
            contentType: "application/json; charset=utf-8",
            async:false,
            url: "<your middle man service url here>/GetQuote?callback=?",
            data: { symbol: 'ctsh' },
            dataType: "jsonp",                
            jsonpCallback: 'fnsuccesscallback'
        });
    });

service (asmx) which will return jsonp:

[WebMethod]
    [ScriptMethod(UseHttpGet = true, ResponseFormat = ResponseFormat.Json)]
    public void GetQuote(String symbol,string callback)
    {          

        WebProxy myProxy = new WebProxy("<proxy url here>", true);

        myProxy.Credentials = new System.Net.NetworkCredential("username", "password", "domain");
        StockQuoteProxy.StockQuote SQ = new StockQuoteProxy.StockQuote();
        SQ.Proxy = myProxy;
        String result = SQ.GetQuote(symbol);
        StringBuilder sb = new StringBuilder();
        JavaScriptSerializer js = new JavaScriptSerializer();
        sb.Append(callback + "(");
        sb.Append(js.Serialize(result));
        sb.Append(");");
        Context.Response.Clear();
        Context.Response.ContentType = "application/json";
        Context.Response.Write(sb.ToString());
        Context.Response.End();         
    }

how to call a variable in code behind to aspx page

You can access a public/protected property using the data binding expression <%# myproperty %> as given below:

    <asp:Label ID="Label1" runat="server" Text="<%#CodeBehindVarPublic %>"></asp:Label>

you should call DataBind method, otherwise it can't be evaluated.

    public partial class WebForm1 : System.Web.UI.Page
    {
     public string CodeBehindVarPublic { get; set; }
      protected void Page_Load(object sender, EventArgs e)
        {
          CodeBehindVarPublic ="xyz";
       //you should call the next line  in case of using <%#CodeBehindVarPublic %>

          DataBind();
        }

}

how to take user input in Array using java?

You can do the following:

    import java.util.Scanner;

    public class Test {

            public static void main(String[] args) {

            int arr[];
            Scanner scan = new Scanner(System.in);
            // If you want to take 5 numbers for user and store it in an int array
            for(int i=0; i<5; i++) {
                System.out.print("Enter number " + (i+1) + ": ");
                arr[i] = scan.nextInt();    // Taking user input
            }

            // For printing those numbers
            for(int i=0; i<5; i++) 
                System.out.println("Number " + (i+1) + ": " + arr[i]);
        }
    }

Cannot delete or update a parent row: a foreign key constraint fails

This happened to me as well and due to a dependency and reference from other tables, I could not remove the entry. What I did is added a delete column (of type boolean) to the table. The value in that field showed whether the item is marked for deletion or not. If marked for deletion, don't fetch/use; otherwise, use it.

How to convert hex to ASCII characters in the Linux shell?

GNU awk 4.1

awk -niord '$0=chr("0x"RT)' RS=.. ORS=

Note that if you echo to this it will produce an extra null byte

$ echo 595a | awk -niord '$0=chr("0x"RT)' RS=.. ORS= | od -tx1c
0000000  59  5a  00
          Y   Z  \0

Instead use printf

$ printf 595a | awk -niord '$0=chr("0x"RT)' RS=.. ORS= | od -tx1c
0000000  59  5a
          Y   Z

Also note that GNU awk produces UTF-8 by default

$ printf a1 | awk -niord '$0=chr("0x"RT)' RS=.. ORS= | od -tx1
0000000 c2 a1

If you are dealing with characters outside of ASCII, and you are going to be Base64 encoding the resultant string, you can disable UTF-8 with -b

echo 5a | sha256sum | awk -bniord 'RT~/\w/,$0=chr("0x"RT)' RS=.. ORS=

TCPDF ERROR: Some data has already been output, can't send PDF file

Add the function ob_end_clean(); before call the Output function. It worked for me within a custom Wordpress function!

ob_end_clean();
$pdf->Output($pdf_name, 'I');

Leader Not Available Kafka in Console Producer

What solved it for me is to set listeners like so:

advertised.listeners = PLAINTEXT://my.public.ip:9092
listeners = PLAINTEXT://0.0.0.0:9092

This makes KAFKA broker listen to all interfaces.

How to show progress dialog in Android?

To use ProgressDialog use the below code

ProgressDialog progressdialog = new ProgressDialog(getApplicationContext());
progressdialog.setMessage("Please Wait....");

To start the ProgressDialog use

progressdialog.show();

progressdialog.setCancelable(false); is used so that ProgressDialog cannot be cancelled until the work is done.

To stop the ProgressDialog use this code (when your work is finished):

progressdialog.dismiss();`

Send raw ZPL to Zebra printer via USB

Install an share your printer: \localhost\zebra Send ZPL as text, try with copy first:

copy file.zpl \localhost\zebra

very simple, almost no coding.

Calling Scalar-valued Functions in SQL

Are you sure it's not a Table-Valued Function?

The reason I ask:

CREATE FUNCTION dbo.chk_mgr(@mgr VARCHAR(50)) 
RETURNS @mgr_table TABLE (mgr_name VARCHAR(50))
AS
BEGIN 
  INSERT @mgr_table (mgr_name) VALUES ('pointy haired boss') 
  RETURN
END 
GO

SELECT dbo.chk_mgr('asdf')
GO

Result:

Msg 4121, Level 16, State 1, Line 1
Cannot find either column "dbo" or the user-defined function 
or aggregate "dbo.chk_mgr", or the name is ambiguous.

However...

SELECT * FROM dbo.chk_mgr('asdf') 

mgr_name
------------------
pointy haired boss

How to access the php.ini file in godaddy shared hosting linux

Procedures:

  • Go to your CPanel
  • Select PHP version
  • Click on the link Switch to PHP options
  • Edit your configuration
  • don't forget to click save

enter image description here

You can also follow this screencast

https://www.youtube.com/watch?v=tdUlIkZcOe0

Calling Objective-C method from C++ member function?

The easiest solution is to simply tell Xcode to compile everything as Objective C++.

Set your project or target settings for Compile Sources As to Objective C++ and recompile.

Then you can use C++ or Objective C everywhere, for example:

void CPPObject::Function( ObjectiveCObject* context, NSView* view )
{
   [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)view.layer]
}

This has the same affect as renaming all your source files from .cpp or .m to .mm.

There are two minor downsides to this: clang cannot analyse C++ source code; some relatively weird C code does not compile under C++.

R - test if first occurrence of string1 is followed by string2

I think it's worth answering the generic question "R - test if string contains string" here.

For that, use the grep function.

# example:
> if(length(grep("ab","aacd"))>0) print("found") else print("Not found")
[1] "Not found"
> if(length(grep("ab","abcd"))>0) print("found") else print("Not found")
[1] "found"

How to do a SOAP wsdl web services call from the command line

curl --header "Content-Type: text/xml;charset=UTF-8" --header "SOAPAction:ACTION_YOU_WANT_TO_CALL" --data @FILE_NAME URL_OF_THE_SERVICE 

Above command was helpful for me

Example

curl --header "Content-Type: text/xml;charset=UTF-8" --header "SOAPAction:urn:GetVehicleLimitedInfo" --data @request.xml http://11.22.33.231:9080/VehicleInfoQueryService.asmx 

More info

Saving results with headers in Sql Server Management Studio

Got here when looking for a way to make SSMS properly escape CSV separators when exporting results.

Guess what? - this is actually an option, and it is unchecked by default. So by default, you get broken CSV files (and may not even realize it, esp. if your export is large and your data doesn't have commas normally) - and you have to go in and click a checkbox so that your CSVs export correctly!

To me, this seems like a monumentally stupid design choice and an apt metaphor for Microsoft's approach to software in general ("broken by default, requires meaningless ritualistic actions to make trivial functionality work").

But I will gladly donate $100 to a charity of respondent's choice if someone can give me one valid real-life reason for this option to exist (i.e., an actual scenario where it was useful).

python location on mac osx

I checked a few similar discussions and found out the best way to locate all python2/python3 builds is:

which -a python python3

How do I tell Spring Boot which main class to use for the executable jar?

For those using Gradle (instead of Maven) :

springBoot {
    mainClass = "com.example.Main"
}

Calling a Sub and returning a value

Private Sub Main()
    Dim value = getValue()
    'do something with value
End Sub

Private Function getValue() As Integer
    Return 3
End Function

How can I use numpy.correlate to do autocorrelation?

I think there are 2 things that add confusion to this topic:

  1. statistical v.s. signal processing definition: as others have pointed out, in statistics we normalize auto-correlation into [-1,1].
  2. partial v.s. non-partial mean/variance: when the timeseries shifts at a lag>0, their overlap size will always < original length. Do we use the mean and std of the original (non-partial), or always compute a new mean and std using the ever changing overlap (partial) makes a difference. (There's probably a formal term for this, but I'm gonna use "partial" for now).

I've created 5 functions that compute auto-correlation of a 1d array, with partial v.s. non-partial distinctions. Some use formula from statistics, some use correlate in the signal processing sense, which can also be done via FFT. But all results are auto-correlations in the statistics definition, so they illustrate how they are linked to each other. Code below:

import numpy
import matplotlib.pyplot as plt

def autocorr1(x,lags):
    '''numpy.corrcoef, partial'''

    corr=[1. if l==0 else numpy.corrcoef(x[l:],x[:-l])[0][1] for l in lags]
    return numpy.array(corr)

def autocorr2(x,lags):
    '''manualy compute, non partial'''

    mean=numpy.mean(x)
    var=numpy.var(x)
    xp=x-mean
    corr=[1. if l==0 else numpy.sum(xp[l:]*xp[:-l])/len(x)/var for l in lags]

    return numpy.array(corr)

def autocorr3(x,lags):
    '''fft, pad 0s, non partial'''

    n=len(x)
    # pad 0s to 2n-1
    ext_size=2*n-1
    # nearest power of 2
    fsize=2**numpy.ceil(numpy.log2(ext_size)).astype('int')

    xp=x-numpy.mean(x)
    var=numpy.var(x)

    # do fft and ifft
    cf=numpy.fft.fft(xp,fsize)
    sf=cf.conjugate()*cf
    corr=numpy.fft.ifft(sf).real
    corr=corr/var/n

    return corr[:len(lags)]

def autocorr4(x,lags):
    '''fft, don't pad 0s, non partial'''
    mean=x.mean()
    var=numpy.var(x)
    xp=x-mean

    cf=numpy.fft.fft(xp)
    sf=cf.conjugate()*cf
    corr=numpy.fft.ifft(sf).real/var/len(x)

    return corr[:len(lags)]

def autocorr5(x,lags):
    '''numpy.correlate, non partial'''
    mean=x.mean()
    var=numpy.var(x)
    xp=x-mean
    corr=numpy.correlate(xp,xp,'full')[len(x)-1:]/var/len(x)

    return corr[:len(lags)]


if __name__=='__main__':

    y=[28,28,26,19,16,24,26,24,24,29,29,27,31,26,38,23,13,14,28,19,19,\
            17,22,2,4,5,7,8,14,14,23]
    y=numpy.array(y).astype('float')

    lags=range(15)
    fig,ax=plt.subplots()

    for funcii, labelii in zip([autocorr1, autocorr2, autocorr3, autocorr4,
        autocorr5], ['np.corrcoef, partial', 'manual, non-partial',
            'fft, pad 0s, non-partial', 'fft, no padding, non-partial',
            'np.correlate, non-partial']):

        cii=funcii(y,lags)
        print(labelii)
        print(cii)
        ax.plot(lags,cii,label=labelii)

    ax.set_xlabel('lag')
    ax.set_ylabel('correlation coefficient')
    ax.legend()
    plt.show()

Here is the output figure:

enter image description here

We don't see all 5 lines because 3 of them overlap (at the purple). The overlaps are all non-partial auto-correlations. This is because computations from the signal processing methods (np.correlate, FFT) don't compute a different mean/std for each overlap.

Also note that the fft, no padding, non-partial (red line) result is different, because it didn't pad the timeseries with 0s before doing FFT, so it's circular FFT. I can't explain in detail why, that's what I learned from elsewhere.

How to properly export an ES6 class in Node 4?

Sometimes I need to declare multiple classes in one file, or I want to export base classes and keep their names exported because of my JetBrains editor understands that better. I just use

global.MyClass = class MyClass { ... };

And somewhere else:

require('baseclasses.js');
class MySubclass extends MyClass() { ... }

C# List of objects, how do I get the sum of a property

And if you need to do it on items that match a specific condition...

double total = myList.Where(item => item.Name == "Eggs").Sum(item => item.Amount);

Get HTML5 localStorage keys

You can use the localStorage.key(index) function to return the string representation, where index is the nth object you want to retrieve.

String.Format alternative in C++

The C++ way would be to use a std::stringstream object as:

std::stringstream fmt;
fmt << a << " " << b << " > " << c;

The C way would be to use sprintf.

The C way is difficult to get right since:

  • It is type unsafe
  • Requires buffer management

Of course, you may want to fall back on the C way if performance is an issue (imagine you are creating fixed-size million little stringstream objects and then throwing them away).

What does <> mean in excel?

It means "not equal to" (as in, the values in cells E37-N37 are not equal to "", or in other words, they are not empty.)

SQL Server tables: what is the difference between @, # and ##?

# and ## tables are actual tables represented in the temp database. These tables can have indexes and statistics, and can be accessed across sprocs in a session (in the case of a global temp table, it is available across sessions).

The @table is a table variable.

For more: http://www.sqlteam.com/article/temporary-tables

When is a C++ destructor called?

Yes, a destructor (a.k.a. dtor) is called when an object goes out of scope if it is on the stack or when you call delete on a pointer to an object.

  1. If the pointer is deleted via delete then the dtor will be called. If you reassign the pointer without calling delete first, you will get a memory leak because the object still exists in memory somewhere. In the latter instance, the dtor is not called.

  2. A good linked list implementation will call the dtor of all objects in the list when the list is being destroyed (because you either called some method to destory it or it went out of scope itself). This is implementation dependent.

  3. I doubt it, but I wouldn't be surprised if there is some odd circumstance out there.

how we add or remove readonly attribute from textbox on clicking radion button in cakephp using jquery?

In your Case you can write the following jquery code:

$(document).ready(function(){

   $('.staff_on_site').click(function(){

     var rBtnVal = $(this).val();

     if(rBtnVal == "yes"){
         $("#no_of_staff").attr("readonly", false); 
     }
     else{ 
         $("#no_of_staff").attr("readonly", true); 
     }
   });
});

Here is the Fiddle: http://jsfiddle.net/P4QWx/3/

jQuery .attr("disabled", "disabled") not working in Chrome

Here:
http://jsbin.com/urize4/edit

Live Preview
http://jsbin.com/urize4/

You should use "readonly" instead like:

$("input[type='text']").attr("readonly", "true");

SSL Connection / Connection Reset with IISExpress

This is anecdotal as overheard from a co-worker, but allegedly this is an issue with chrome forcing https. I usually launch in firefox so i hadn't seen this problem before. Using firefox or ie worked for my co-worker.

Sort tuples based on second parameter

    def findMaxSales(listoftuples):
        newlist = []
        tuple = ()
        for item in listoftuples:
             movie = item[0]
             value = (item[1])
             tuple = value, movie

             newlist += [tuple]
             newlist.sort()
             highest = newlist[-1]
             result = highest[1]
       return result

             movieList = [("Finding Dory", 486), ("Captain America: Civil                      

             War", 408), ("Deadpool", 363), ("Zootopia", 341), ("Rogue One", 529), ("The  Secret Life of Pets", 368), ("Batman v Superman", 330), ("Sing", 268), ("Suicide Squad", 325), ("The Jungle Book", 364)]
             print(findMaxSales(movieList))

output --> Rogue One

How can I select an element in a component template?

Angular 4+: Use renderer.selectRootElement with a CSS selector to access the element.

I've got a form that initially displays an email input. After the email is entered, the form will be expanded to allow them to continue adding information relating to their project. However, if they are not an existing client, the form will include an address section above the project information section.

As of now, the data entry portion has not been broken up into components, so the sections are managed with *ngIf directives. I need to set focus on the project notes field if they are an existing client, or the first name field if they are new.

I tried the solutions with no success. However, Update 3 in this answer gave me half of the eventual solution. The other half came from MatteoNY's response in this thread. The result is this:

import { NgZone, Renderer } from '@angular/core';

constructor(private ngZone: NgZone, private renderer: Renderer) {}

setFocus(selector: string): void {
    this.ngZone.runOutsideAngular(() => {
        setTimeout(() => {
            this.renderer.selectRootElement(selector).focus();
        }, 0);
    });
}

submitEmail(email: string): void {
    // Verify existence of customer
    ...
    if (this.newCustomer) {
        this.setFocus('#firstname');
    } else {
        this.setFocus('#description');
    }
}

Since the only thing I'm doing is setting the focus on an element, I don't need to concern myself with change detection, so I can actually run the call to renderer.selectRootElement outside of Angular. Because I need to give the new sections time to render, the element section is wrapped in a timeout to allow the rendering threads time to catch up before the element selection is attempted. Once all that is setup, I can simply call the element using basic CSS selectors.

I know this example dealt primarily with the focus event, but it's hard for me that this couldn't be used in other contexts.

UPDATE: Angular dropped support for Renderer in Angular 4 and removed it completely in Angular 9. This solution should not be impacted by the migration to Renderer2. Please refer to this link for additional information: Renderer migration to Renderer2

How to pass command-line arguments to a PowerShell ps1 file

You could declare your parameters in the file, like param:

[string]$para1
[string]$param2

And then call the PowerShell file like so .\temp.ps1 para1 para2....para10, etc.

Explanation of polkitd Unregistered Authentication Agent

I found this problem too. Because centos service depend on multi-user.target for none desktop Cenots 7.2. so I delete multi-user.target from my .service file. It had missed.

getting a checkbox array value from POST

// if you do the input like this
<input id="'.$userid.'" value="'.$userid.'"  name="invite['.$userid.']" type="checkbox">

// you can access the value directly like this:
$invite = $_POST['invite'][$userid];

JavaScript closures vs. anonymous functions

You are both using closures.

I 'm going with the Wikipedia definition here:

In computer science, a closure (also lexical closure or function closure) is a function or reference to a function together with a referencing environment—a table storing a reference to each of the non-local variables (also called free variables) of that function. A closure—unlike a plain function pointer—allows a function to access those non-local variables even when invoked outside of its immediate lexical scope.

Your friend's attempt clearly uses the variable i, which is non-local, by taking its value and making a copy to store into the local i2.

Your own attempt passes i (which at the call site is in scope) to an anonymous function as an argument. This is not a closure so far, but then that function returns another function that references the same i2. Since inside the inner anonymous function i2 is not a local, this creates a closure.

Relative paths in Python

summary of the most important commands

>>> import os
>>> os.path.join('/home/user/tmp', 'subfolder')
'/home/user/tmp/subfolder'
>>> os.path.normpath('/home/user/tmp/../test/..')
'/home/user'
>>> os.path.relpath('/home/user/tmp', '/home/user')
'tmp'
>>> os.path.isabs('/home/user/tmp')
True
>>> os.path.isabs('/tmp')
True
>>> os.path.isabs('tmp')
False
>>> os.path.isabs('./../tmp')
False
>>> os.path.realpath('/home/user/tmp/../test/..') # follows symbolic links
'/home/user'

A detailed description is found in the docs. These are linux paths. Windows should work analogous.

How to read .pem file to get private and public key

One option is to use bouncycastle's PEMParser:

Class for parsing OpenSSL PEM encoded streams containing X509 certificates, PKCS8 encoded keys and PKCS7 objects.

In the case of PKCS7 objects the reader will return a CMS ContentInfo object. Public keys will be returned as well formed SubjectPublicKeyInfo objects, private keys will be returned as well formed PrivateKeyInfo objects. In the case of a private key a PEMKeyPair will normally be returned if the encoding contains both the private and public key definition. CRLs, Certificates, PKCS#10 requests, and Attribute Certificates will generate the appropriate BC holder class.

Here is an example of using the Parser test code:

package org.bouncycastle.openssl.test;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.math.BigInteger;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Security;
import java.security.Signature;
import java.security.interfaces.DSAPrivateKey;
import java.security.interfaces.RSAPrivateCrtKey;
import java.security.interfaces.RSAPrivateKey;

import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.cms.CMSObjectIdentifiers;
import org.bouncycastle.asn1.cms.ContentInfo;
import org.bouncycastle.asn1.pkcs.PrivateKeyInfo;
import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import org.bouncycastle.asn1.x9.ECNamedCurveTable;
import org.bouncycastle.asn1.x9.X9ECParameters;
import org.bouncycastle.cert.X509CertificateHolder;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openssl.PEMDecryptorProvider;
import org.bouncycastle.openssl.PEMEncryptedKeyPair;
import org.bouncycastle.openssl.PEMKeyPair;
import org.bouncycastle.openssl.PEMParser;
import org.bouncycastle.openssl.PEMWriter;
import org.bouncycastle.openssl.PasswordFinder;
import org.bouncycastle.openssl.jcajce.JcaPEMKeyConverter;
import org.bouncycastle.openssl.jcajce.JceOpenSSLPKCS8DecryptorProviderBuilder;
import org.bouncycastle.openssl.jcajce.JcePEMDecryptorProviderBuilder;
import org.bouncycastle.operator.InputDecryptorProvider;
import org.bouncycastle.pkcs.PKCS8EncryptedPrivateKeyInfo;
import org.bouncycastle.util.test.SimpleTest;

/**
 * basic class for reading test.pem - the password is "secret"
 */
public class ParserTest
    extends SimpleTest
{
    private static class Password
        implements PasswordFinder
    {
        char[]  password;

        Password(
            char[] word)
        {
            this.password = word;
        }

        public char[] getPassword()
        {
            return password;
        }
    }

    public String getName()
    {
        return "PEMParserTest";
    }

    private PEMParser openPEMResource(
        String          fileName)
    {
        InputStream res = this.getClass().getResourceAsStream(fileName);
        Reader fRd = new BufferedReader(new InputStreamReader(res));
        return new PEMParser(fRd);
    }

    public void performTest()
        throws Exception
    {
        PEMParser       pemRd = openPEMResource("test.pem");
        Object          o;
        PEMKeyPair      pemPair;
        KeyPair         pair;

        while ((o = pemRd.readObject()) != null)
        {
            if (o instanceof KeyPair)
            {
                //pair = (KeyPair)o;

                //System.out.println(pair.getPublic());
                //System.out.println(pair.getPrivate());
            }
            else
            {
                //System.out.println(o.toString());
            }
        }

        // test bogus lines before begin are ignored.
        pemRd = openPEMResource("extratest.pem");

        while ((o = pemRd.readObject()) != null)
        {
            if (!(o instanceof X509CertificateHolder))
            {
                fail("wrong object found");
            }
        }

        //
        // pkcs 7 data
        //
        pemRd = openPEMResource("pkcs7.pem");
        ContentInfo d = (ContentInfo)pemRd.readObject();

        if (!d.getContentType().equals(CMSObjectIdentifiers.envelopedData))
        {
            fail("failed envelopedData check");
        }

        //
        // ECKey
        //
        pemRd = openPEMResource("eckey.pem");
        ASN1ObjectIdentifier ecOID = (ASN1ObjectIdentifier)pemRd.readObject();
        X9ECParameters ecSpec = ECNamedCurveTable.getByOID(ecOID);

        if (ecSpec == null)
        {
            fail("ecSpec not found for named curve");
        }

        pemPair = (PEMKeyPair)pemRd.readObject();

        pair = new JcaPEMKeyConverter().setProvider("BC").getKeyPair(pemPair);

        Signature sgr = Signature.getInstance("ECDSA", "BC");

        sgr.initSign(pair.getPrivate());

        byte[] message = new byte[] { (byte)'a', (byte)'b', (byte)'c' };

        sgr.update(message);

        byte[]  sigBytes = sgr.sign();

        sgr.initVerify(pair.getPublic());

        sgr.update(message);

        if (!sgr.verify(sigBytes))
        {
            fail("EC verification failed");
        }

        if (!pair.getPublic().getAlgorithm().equals("ECDSA"))
        {
            fail("wrong algorithm name on public got: " + pair.getPublic().getAlgorithm());
        }

        if (!pair.getPrivate().getAlgorithm().equals("ECDSA"))
        {
            fail("wrong algorithm name on private");
        }

        //
        // ECKey -- explicit parameters
        //
        pemRd = openPEMResource("ecexpparam.pem");
        ecSpec = (X9ECParameters)pemRd.readObject();

        pemPair = (PEMKeyPair)pemRd.readObject();

        pair = new JcaPEMKeyConverter().setProvider("BC").getKeyPair(pemPair);

        sgr = Signature.getInstance("ECDSA", "BC");

        sgr.initSign(pair.getPrivate());

        message = new byte[] { (byte)'a', (byte)'b', (byte)'c' };

        sgr.update(message);

        sigBytes = sgr.sign();

        sgr.initVerify(pair.getPublic());

        sgr.update(message);

        if (!sgr.verify(sigBytes))
        {
            fail("EC verification failed");
        }

        if (!pair.getPublic().getAlgorithm().equals("ECDSA"))
        {
            fail("wrong algorithm name on public got: " + pair.getPublic().getAlgorithm());
        }

        if (!pair.getPrivate().getAlgorithm().equals("ECDSA"))
        {
            fail("wrong algorithm name on private");
        }

        //
        // writer/parser test
        //
        KeyPairGenerator      kpGen = KeyPairGenerator.getInstance("RSA", "BC");

        pair = kpGen.generateKeyPair();

        keyPairTest("RSA", pair);

        kpGen = KeyPairGenerator.getInstance("DSA", "BC");
        kpGen.initialize(512, new SecureRandom());
        pair = kpGen.generateKeyPair();

        keyPairTest("DSA", pair);

        //
        // PKCS7
        //
        ByteArrayOutputStream bOut = new ByteArrayOutputStream();
        PEMWriter             pWrt = new PEMWriter(new OutputStreamWriter(bOut));

        pWrt.writeObject(d);

        pWrt.close();

        pemRd = new PEMParser(new InputStreamReader(new ByteArrayInputStream(bOut.toByteArray())));
        d = (ContentInfo)pemRd.readObject();

        if (!d.getContentType().equals(CMSObjectIdentifiers.envelopedData))
        {
            fail("failed envelopedData recode check");
        }


        // OpenSSL test cases (as embedded resources)
        doOpenSslDsaTest("unencrypted");
        doOpenSslRsaTest("unencrypted");

        doOpenSslTests("aes128");
        doOpenSslTests("aes192");
        doOpenSslTests("aes256");
        doOpenSslTests("blowfish");
        doOpenSslTests("des1");
        doOpenSslTests("des2");
        doOpenSslTests("des3");
        doOpenSslTests("rc2_128");

        doOpenSslDsaTest("rc2_40_cbc");
        doOpenSslRsaTest("rc2_40_cbc");
        doOpenSslDsaTest("rc2_64_cbc");
        doOpenSslRsaTest("rc2_64_cbc");

        doDudPasswordTest("7fd98", 0, "corrupted stream - out of bounds length found");
        doDudPasswordTest("ef677", 1, "corrupted stream - out of bounds length found");
        doDudPasswordTest("800ce", 2, "unknown tag 26 encountered");
        doDudPasswordTest("b6cd8", 3, "DEF length 81 object truncated by 56");
        doDudPasswordTest("28ce09", 4, "DEF length 110 object truncated by 28");
        doDudPasswordTest("2ac3b9", 5, "DER length more than 4 bytes: 11");
        doDudPasswordTest("2cba96", 6, "DEF length 100 object truncated by 35");
        doDudPasswordTest("2e3354", 7, "DEF length 42 object truncated by 9");
        doDudPasswordTest("2f4142", 8, "DER length more than 4 bytes: 14");
        doDudPasswordTest("2fe9bb", 9, "DER length more than 4 bytes: 65");
        doDudPasswordTest("3ee7a8", 10, "DER length more than 4 bytes: 57");
        doDudPasswordTest("41af75", 11, "unknown tag 16 encountered");
        doDudPasswordTest("1704a5", 12, "corrupted stream detected");
        doDudPasswordTest("1c5822", 13, "unknown object in getInstance: org.bouncycastle.asn1.DERUTF8String");
        doDudPasswordTest("5a3d16", 14, "corrupted stream detected");
        doDudPasswordTest("8d0c97", 15, "corrupted stream detected");
        doDudPasswordTest("bc0daf", 16, "corrupted stream detected");
        doDudPasswordTest("aaf9c4d",17, "corrupted stream - out of bounds length found");

        doNoPasswordTest();

        // encrypted private key test
        InputDecryptorProvider pkcs8Prov = new JceOpenSSLPKCS8DecryptorProviderBuilder().build("password".toCharArray());
        pemRd = openPEMResource("enckey.pem");

        PKCS8EncryptedPrivateKeyInfo encPrivKeyInfo = (PKCS8EncryptedPrivateKeyInfo)pemRd.readObject();
        JcaPEMKeyConverter   converter = new JcaPEMKeyConverter().setProvider("BC");

        RSAPrivateCrtKey privKey = (RSAPrivateCrtKey)converter.getPrivateKey(encPrivKeyInfo.decryptPrivateKeyInfo(pkcs8Prov));

        if (!privKey.getPublicExponent().equals(new BigInteger("10001", 16)))
        {
            fail("decryption of private key data check failed");
        }

        // general PKCS8 test

        pemRd = openPEMResource("pkcs8test.pem");

        Object privInfo;

        while ((privInfo = pemRd.readObject()) != null)
        {
            if (privInfo instanceof PrivateKeyInfo)
            {
                privKey = (RSAPrivateCrtKey)converter.getPrivateKey(PrivateKeyInfo.getInstance(privInfo));
            }
            else
            {
                privKey = (RSAPrivateCrtKey)converter.getPrivateKey(((PKCS8EncryptedPrivateKeyInfo)privInfo).decryptPrivateKeyInfo(pkcs8Prov));
            }
            if (!privKey.getPublicExponent().equals(new BigInteger("10001", 16)))
            {
                fail("decryption of private key data check failed");
            }
        }
    }

    private void keyPairTest(
        String   name,
        KeyPair pair) 
        throws IOException
    {
        PEMParser pemRd;
        ByteArrayOutputStream bOut = new ByteArrayOutputStream();
        PEMWriter             pWrt = new PEMWriter(new OutputStreamWriter(bOut));

        pWrt.writeObject(pair.getPublic());

        pWrt.close();

        pemRd = new PEMParser(new InputStreamReader(new ByteArrayInputStream(bOut.toByteArray())));

        SubjectPublicKeyInfo pub = SubjectPublicKeyInfo.getInstance(pemRd.readObject());
        JcaPEMKeyConverter   converter = new JcaPEMKeyConverter().setProvider("BC");

        PublicKey k = converter.getPublicKey(pub);

        if (!k.equals(pair.getPublic()))
        {
            fail("Failed public key read: " + name);
        }

        bOut = new ByteArrayOutputStream();
        pWrt = new PEMWriter(new OutputStreamWriter(bOut));

        pWrt.writeObject(pair.getPrivate());

        pWrt.close();

        pemRd = new PEMParser(new InputStreamReader(new ByteArrayInputStream(bOut.toByteArray())));

        KeyPair kPair = converter.getKeyPair((PEMKeyPair)pemRd.readObject());
        if (!kPair.getPrivate().equals(pair.getPrivate()))
        {
            fail("Failed private key read: " + name);
        }

        if (!kPair.getPublic().equals(pair.getPublic()))
        {
            fail("Failed private key public read: " + name);
        }
    }

    private void doOpenSslTests(
        String baseName)
        throws IOException
    {
        doOpenSslDsaModesTest(baseName);
        doOpenSslRsaModesTest(baseName);
    }

    private void doOpenSslDsaModesTest(
        String baseName)
        throws IOException
    {
        doOpenSslDsaTest(baseName + "_cbc");
        doOpenSslDsaTest(baseName + "_cfb");
        doOpenSslDsaTest(baseName + "_ecb");
        doOpenSslDsaTest(baseName + "_ofb");
    }

    private void doOpenSslRsaModesTest(
        String baseName)
        throws IOException
    {
        doOpenSslRsaTest(baseName + "_cbc");
        doOpenSslRsaTest(baseName + "_cfb");
        doOpenSslRsaTest(baseName + "_ecb");
        doOpenSslRsaTest(baseName + "_ofb");
    }

    private void doOpenSslDsaTest(
        String name)
        throws IOException
    {
        String fileName = "dsa/openssl_dsa_" + name + ".pem";

        doOpenSslTestFile(fileName, DSAPrivateKey.class);
    }

    private void doOpenSslRsaTest(
        String name)
        throws IOException
    {
        String fileName = "rsa/openssl_rsa_" + name + ".pem";

        doOpenSslTestFile(fileName, RSAPrivateKey.class);
    }

    private void doOpenSslTestFile(
        String  fileName,
        Class   expectedPrivKeyClass)
        throws IOException
    {
        JcaPEMKeyConverter   converter = new JcaPEMKeyConverter().setProvider("BC");
        PEMDecryptorProvider decProv = new JcePEMDecryptorProviderBuilder().setProvider("BC").build("changeit".toCharArray());
        PEMParser pr = openPEMResource("data/" + fileName);
        Object o = pr.readObject();

        if (o == null || !((o instanceof PEMKeyPair) || (o instanceof PEMEncryptedKeyPair)))
        {
            fail("Didn't find OpenSSL key");
        }

        KeyPair kp = (o instanceof PEMEncryptedKeyPair) ?
            converter.getKeyPair(((PEMEncryptedKeyPair)o).decryptKeyPair(decProv)) : converter.getKeyPair((PEMKeyPair)o);

        PrivateKey privKey = kp.getPrivate();

        if (!expectedPrivKeyClass.isInstance(privKey))
        {
            fail("Returned key not of correct type");
        }
    }

    private void doDudPasswordTest(String password, int index, String message)
    {
        // illegal state exception check - in this case the wrong password will
        // cause an underlying class cast exception.
        try
        {
            PEMDecryptorProvider decProv = new JcePEMDecryptorProviderBuilder().setProvider("BC").build(password.toCharArray());

            PEMParser pemRd = openPEMResource("test.pem");
            Object o;

            while ((o = pemRd.readObject()) != null)
            {
                if (o instanceof PEMEncryptedKeyPair)
                {
                    ((PEMEncryptedKeyPair)o).decryptKeyPair(decProv);
                }
            }

            fail("issue not detected: " + index);
        }
        catch (IOException e)
        {
            if (e.getCause() != null && !e.getCause().getMessage().endsWith(message))
            {
               fail("issue " + index + " exception thrown, but wrong message");
            }
            else if (e.getCause() == null && !e.getMessage().equals(message))
            {
                               e.printStackTrace();
               fail("issue " + index + " exception thrown, but wrong message");
            }
        }
    }

    private void doNoPasswordTest()
        throws IOException
    {
        PEMDecryptorProvider decProv = new JcePEMDecryptorProviderBuilder().setProvider("BC").build("".toCharArray());

        PEMParser pemRd = openPEMResource("smimenopw.pem");
        Object o;
        PrivateKeyInfo key = null;

        while ((o = pemRd.readObject()) != null)
        {
             key = (PrivateKeyInfo)o;
        }

        if (key == null)
        {
            fail("private key not detected");
        }
    }

    public static void main(
        String[]    args)
    {
        Security.addProvider(new BouncyCastleProvider());

        runTest(new ParserTest());
    }
}

How to implement class constructor in Visual Basic?

A class with a field:

Public Class MyStudent
   Public StudentId As Integer

The constructor:

    Public Sub New(newStudentId As Integer)
        StudentId = newStudentId
    End Sub
End Class

Using Javascript can you get the value from a session attribute set by servlet in the HTML page

<?php 
    $sessionDetails = $this->Session->read('Auth.User');

    if (!empty($sessionDetails)) {


        $loginFlag = 1;
        # code...
    }else{
        $loginFlag =  0;
    }


?>

<script type="text/javascript">

    var sessionValue = '<?php echo $loginFlag; ?>';
    if (sessionValue = 0) {

        //model show
    }
</script>

How to solve error "Missing `secret_key_base` for 'production' environment" (Rails 4.1)

This worked for me.

SSH into your production server and cd into your current directory, run bundle exec rake secret or rake secret, you will get a long string as an output, copy that string.

Now run sudo nano /etc/environment.

Paste at the bottom of the file

export SECRET_KEY_BASE=rake secret
ruby -e 'p ENV["SECRET_KEY_BASE"]'

Where rake secret is the string you just copied, paste that copied string in place of rake secret.

Restart the server and test by running echo $SECRET_KEY_BASE.

How to get calendar Quarter from a date in TSQL

To get the exact output you requested, you can use the below:

CAST(DATEPART(YEAR, @Date) AS NVARCHAR(10)) + ' - Q' + CAST(DATEPART(QUARTER, @Date) AS NVARCHAR(10))

This will give you an outputs like: "2015 - Q1", "2013 - Q3", etc.

How can I delete all cookies with JavaScript?

This is a function we are using in our application and it is working fine.

delete cookie: No argument method

function clearListCookies()
{   
    var cookies = document.cookie.split(";");
    for (var i = 0; i < cookies.length; i++)
    {   
        var spcook =  cookies[i].split("=");
        deleteCookie(spcook[0]);
    }
    function deleteCookie(cookiename)
    {
        var d = new Date();
        d.setDate(d.getDate() - 1);
        var expires = ";expires="+d;
        var name=cookiename;
        //alert(name);
        var value="";
        document.cookie = name + "=" + value + expires + "; path=/acc/html";                    
    }
    window.location = ""; // TO REFRESH THE PAGE
}

Edit: This will delete the cookie by setting it to yesterday's date.

sudo: docker-compose: command not found

The output of dpkg -s ... demonstrates that docker-compose is not installed from a package. Without more information from you there are at least two possibilities:

  1. docker-compose simply isn't installed at all, and you need to install it.

    The solution here is simple: install docker-compose.

  2. docker-compose is installed in your $HOME directory (or other location not on root's $PATH).

    There are several solution in this case. The easiest is probably to replace:

    sudo docker-compose ...
    

    With:

    sudo `which docker-compose` ...
    

    This will call sudo with the full path to docker-compose.

    You could alternatively install docker-compose into a system-wide directory, such as /usr/local/bin.

What is the difference between signed and unsigned int

Sometimes we know in advance that the value stored in a given integer variable will always be positive-when it is being used to only count things, for example. In such a case we can declare the variable to be unsigned, as in, unsigned int num student;. With such a declaration, the range of permissible integer values (for a 32-bit compiler) will shift from the range -2147483648 to +2147483647 to range 0 to 4294967295. Thus, declaring an integer as unsigned almost doubles the size of the largest possible value that it can otherwise hold.

SQL Bulk Insert with FIRSTROW parameter skips the following line

You can use the below snippet

BULK INSERT TextData
FROM 'E:\filefromabove.txt'
WITH
(
FIRSTROW = 2,
FIELDTERMINATOR = '|',  --CSV field delimiter
ROWTERMINATOR = '\n',   --Use to shift the control to next row
ERRORFILE = 'E:\ErrorRows.csv',
TABLOCK
)

SQL MERGE statement to update data

Update energydata set energydata.kWh = temp.kWh 
where energydata.webmeterID = (select webmeterID from temp_energydata as temp) 

how does array[100] = {0} set the entire array to 0?

It's not magic.

The behavior of this code in C is described in section 6.7.8.21 of the C specification (online draft of C spec): for the elements that don't have a specified value, the compiler initializes pointers to NULL and arithmetic types to zero (and recursively applies this to aggregates).

The behavior of this code in C++ is described in section 8.5.1.7 of the C++ specification (online draft of C++ spec): the compiler aggregate-initializes the elements that don't have a specified value.

Also, note that in C++ (but not C), you can use an empty initializer list, causing the compiler to aggregate-initialize all of the elements of the array:

char array[100] = {};

As for what sort of code the compiler might generate when you do this, take a look at this question: Strange assembly from array 0-initialization

What to use instead of "addPreferencesFromResource" in a PreferenceActivity?

No alternative method is provided in the method's description because the preferred approach (as of API level 11) is to instantiate PreferenceFragment objects to load your preferences from a resource file. See the sample code here: PreferenceActivity

Match everything except for specified strings

All except word "red"

_x000D_
_x000D_
var href = '(text-1) (red) (text-3) (text-4) (text-5)';_x000D_
_x000D_
var test = href.replace(/\((\b(?!red\b)[\s\S]*?)\)/g, testF); _x000D_
_x000D_
function testF(match, p1, p2, offset, str_full) {_x000D_
  p1 = "-"+p1+"-";_x000D_
  return p1;_x000D_
}_x000D_
_x000D_
console.log(test);
_x000D_
_x000D_
_x000D_

All except word "red"

_x000D_
_x000D_
var href = '(text-1) (frede) (text-3) (text-4) (text-5)';_x000D_
_x000D_
var test = href.replace(/\(([\s\S]*?)\)/g, testF); _x000D_
_x000D_
function testF(match, p1, p2, offset, str_full) {_x000D_
  p1 = p1.replace(/red/g, '');_x000D_
  p1 = "-"+p1+"-";_x000D_
  return p1;_x000D_
}_x000D_
_x000D_
console.log(test);
_x000D_
_x000D_
_x000D_

How to Cast Objects in PHP

You can opt for this example below. Hope it will help.

/** @var ClassName $object */

$object->whateverMethod() // any method defined in the class can be accessed by $object

I know this is not a cast but it can be useful sometimes.

How to send post request with x-www-form-urlencoded body

string urlParameters = "param1=value1&param2=value2";
string _endPointName = "your url post api";

var httpWebRequest = (HttpWebRequest)WebRequest.Create(_endPointName);

httpWebRequest.ContentType = "application/x-www-form-urlencoded";
httpWebRequest.Method = "POST";
httpWebRequest.Headers["ContentType"] = "application/x-www-form-urlencoded";

System.Net.ServicePointManager.ServerCertificateValidationCallback +=
                                                  (se, cert, chain, sslerror) =>
                                                  {
                                                      return true;
                                                  };


using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
                {
                    streamWriter.Write(urlParameters);
                    streamWriter.Flush();
                    streamWriter.Close();
                }
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();

using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
                {
                    var result = streamReader.ReadToEnd();
                }

cut or awk command to print first field of first row

Try

sed 'NUMq;d'  /etc/*release | awk {'print $1}'

where NUM is line number

ex. sed '1q;d'  /etc/*release | awk {'print $1}'

call javascript function onchange event of dropdown list

using jQuery

 $("#ddl").change(function () {
                alert($(this).val());
            });

jsFiddle

Get total number of items on Json object?

In addition to kieran's answer, apparently, modern browsers have an Object.keys function. In this case, you could do this:

Object.keys(jsonArray).length;

More details in this answer on How to list the properties of a javascript object

How can I write variables inside the tasks file in ansible

Whenever you have a module followed by a variable on the same line in ansible the parser will treat the reference variable as the beginning of an in-line dictionary. For example:

- name: some example
  command: {{ myapp }} -a foo

The default here is to parse the first part of {{ myapp }} -a foo as a dictionary instead of a string and you will get an error.

So you must quote the argument like so:

- name: some example
  command: "{{ myapp }} -a foo"

In MVC, how do I return a string result?

There Are 2 ways to return a string from the controller to the view:

First

You could return only the string, but it will not be included in your .cshtml file. it will be just a string appearing in your browser.


Second

You could return a string as the Model object of View Result.

Here is the code sample to do this:

public class HomeController : Controller
{
    // GET: Home
    // this will return just a string, not html
    public string index()
    {
        return "URL to show";
    }

    public ViewResult AutoProperty()
    {   
        string s = "this is a string ";
        // name of view , object you will pass
        return View("Result", s);

    }
}

In the view file to run AutoProperty, It will redirect you to the Result view and will send s
code to the view

<!--this will make this file accept string as it's model-->
@model string

@{
    Layout = null;
}

<!DOCTYPE html>

<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Result</title>
</head>
<body>
    <!--this will represent the string -->
    @Model
</body>
</html>

I run this at http://localhost:60227/Home/AutoProperty.

How to tell git to use the correct identity (name and email) for a given project?

If you don't use the --global parameter it will set the variables for the current project only.

How to call Base Class's __init__ method from the child class?

You can call the super class's constructor like this

class A(object):
    def __init__(self, number):
        print "parent", number

class B(A):
    def __init__(self):
        super(B, self).__init__(5)

b = B()

NOTE:

This will work only when the parent class inherits object

SQLite error 'attempt to write a readonly database' during insert?

This can be caused by SELinux. If you don't want to disable SELinux completely, you need to set the db directory fcontext to httpd_sys_rw_content_t.

semanage fcontext -a -t httpd_sys_rw_content_t "/var/www/railsapp/db(/.*)?"
restorecon -v /var/www/railsapp/db

WARNING: Exception encountered during context initialization - cancelling refresh attempt

This was my stupidity, but a stupidity that was not easy to identify :).

Problem:

  1. My code is compiled on Jdk 1.8.
  2. My eclipse, had JDK 1.8 as the compiler.
  3. My tomcat in eclipse was using Java 1.7 for its container, hence it was not able to understand the .class files which were compiled using 1.8.
  4. To avoid the problem, ensure in your eclipse, double click on your server -> Open Launch configuration -> Classpath -> JRE System Library -> Give the JDK/JRE of the compiled version of java class, in my case, it had to be JDK 1.8
    1. Post this, clean the server, build and redeploy, start the tomcat.

If you are deploying manually into your server, ensure your JAVA_HOME, JDK_HOME points to the correct JDK which you used to compile the project and build the war.

If you do not like to change JAVA_HOME, JDK_HOME, you can always change the JAVA_HOME and JDK_HOME in catalina.bat(for tomcat server) and that'll enable your life to be easy!

Git Bash is extremely slow on Windows 7 x64

Combined answers:

  1. Wilbert's - what info to include in PS1
  2. sinelaw's - (<branch_name>) or (<sha>)
# https://unix.stackexchange.com/questions/140610/using-variables-to-store-terminal-color-codes-for-ps1/140618#140618
# https://unix.stackexchange.com/questions/124407/what-color-codes-can-i-use-in-my-ps1-prompt
# \033 is the same as \e
# 0;32 is the same as 32
CYAN="$(echo -e "\e[1;36m")"
GREEN="$(echo -e "\e[32m")"
YELLOW="$(echo -e "\e[33m")"
RESET="$(echo -e "\e[0m")"

# https://stackoverflow.com/questions/4485059/git-bash-is-extremely-slow-in-windows-7-x64/19500237#19500237
# https://stackoverflow.com/questions/4485059/git-bash-is-extremely-slow-in-windows-7-x64/13476961#13476961
# https://stackoverflow.com/questions/39518124/check-if-directory-is-git-repository-without-having-to-cd-into-it/39518382#39518382
fast_git_ps1 ()
{
    git -C . rev-parse 2>/dev/null && echo " ($((git symbolic-ref --short -q HEAD || git rev-parse -q --short HEAD) 2> /dev/null))"
}

# you need \] at the end for colors
# Don't set \[ at the beginning or ctrl+up for history will work strangely
PS1='${GREEN}\u@\h ${YELLOW}\w${CYAN}$(fast_git_ps1)${RESET}\] $ '

Result:

frolowr@RWAMW36650 /c/projects/elm-math-kids (master) $

Selenium Web Driver & Java. Element is not clickable at point (x, y). Other element would receive the click

If element is not clickable and overlay issue is ocuring we use arguments[0].click().

WebElement ele = driver.findElement(By.xpath("//div[@class='input-group-btn']/input")); JavascriptExecutor executor = (JavascriptExecutor)driver; executor.executeScript("arguments[0].click();", ele);

How do I make UITableViewCell's ImageView a fixed size even when the image is smaller

A Simply Swift,

Step 1: Create One SubClass of UITableViewCell
Step 2: Add this method to SubClass of UITableViewCell

override func layoutSubviews() {
    super.layoutSubviews()
    self.imageView?.frame = CGRectMake(0, 0, 10, 10)
}

Step 3: Create cell object using that SubClass in cellForRowAtIndexPath,

Ex: let customCell:CustomCell = CustomCell(style: UITableViewCellStyle.Default, reuseIdentifier: "Cell")

Step 4: Enjoy

Compiler error: "initializer element is not a compile-time constant"

The reason is that your are defining your imageSegment outside of a function in your source code (static variable).

In such cases, the initialization cannot include execution of code, like calling a function or allocation a class. Initializer must be a constant whose value is known at compile time.

You can then initialize your static variable inside of your init method (if you postpone its declaration to init).

How to solve "The specified service has been marked for deletion" error

In my case, I execute taskkill /f /im dongleserver.exe , where dongleserver.exe is my program's exe file.

Then I can able to reinstall my program already.

How to sleep the thread in node.js without affecting other threads?

Please consider the deasync module, personally I don't like the Promise way to make all functions async, and keyword async/await anythere. And I think the official node.js should consider to expose the event loop API, this will solve the callback hell simply. Node.js is a framework not a language.

var node = require("deasync");
node.loop = node.runLoopOnce;

var done = 0;
// async call here
db.query("select * from ticket", (error, results, fields)=>{
    done = 1;
});

while (!done)
    node.loop();

// Now, here you go

Django - taking values from POST request

If you need to do something on the front end you can respond to the onsubmit event of your form. If you are just posting to admin/start you can access post variables in your view through the request object. request.POST which is a dictionary of post variables

How to remove newlines from beginning and end of a string?

Use String.trim() method to get rid of whitespaces (spaces, new lines etc.) from the beginning and end of the string.

String trimmedString = myString.trim();

MySQL error 1241: Operand should contain 1 column(s)

Another way to make the parser raise the same exception is the following incorrect clause.

SELECT r.name
FROM roles r
WHERE id IN ( SELECT role_id ,
                     system_user_id
                 FROM role_members m
                 WHERE r.id = m.role_id
                 AND m.system_user_id = intIdSystemUser
             )

The nested SELECT statement in the IN clause returns two columns, which the parser sees as operands, which is technically correct, since the id column matches values from but one column (role_id) in the result returned by the nested select statement, which is expected to return a list.

For sake of completeness, the correct syntax is as follows.

SELECT r.name
FROM roles r
WHERE id IN ( SELECT role_id
                 FROM role_members m
                 WHERE r.id = m.role_id
                 AND m.system_user_id = intIdSystemUser
             )

The stored procedure of which this query is a portion not only parsed, but returned the expected result.

How to hide Android soft keyboard on EditText

After long time looking into TextView class I found a way to prevent keyboard to appears. The trick is hide it right after it appears, so I searched a method that is called after keyboard appear and hide it.

Implemented EditText class

public class NoImeEditText extends EditText {

    public NoImeEditText(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    /**
     * This method is called before keyboard appears when text is selected.
     * So just hide the keyboard
     * @return
     */
    @Override
    public boolean onCheckIsTextEditor() {
        hideKeyboard();

        return super.onCheckIsTextEditor();
    }

    /**
     * This methdod is called when text selection is changed, so hide keyboard to prevent it to appear
     * @param selStart
     * @param selEnd
     */
    @Override
    protected void onSelectionChanged(int selStart, int selEnd) {
        super.onSelectionChanged(selStart, selEnd);

        hideKeyboard();
    }

    private void hideKeyboard(){
        InputMethodManager imm = (InputMethodManager) getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.hideSoftInputFromWindow(getWindowToken(), 0);
    }
}

and style

<com.my.app.CustomViews.NoImeEditText
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:editable="false"
    android:background="@null"
    android:textSize="@dimen/cell_text" />

jQuery UI Dialog OnBeforeUnload

For ASP.NET MVC if you want to make an exception for leaving the page via submitting a particular form:

Set a form id:

@using (Html.BeginForm("Create", "MgtJob", FormMethod.Post, new { id = "createjob" }))
{
  // Your code
}



<script type="text/javascript">

  // Without submit form
   $(window).bind('beforeunload', function () {
        if ($('input').val() !== '') {
            return "It looks like you have input you haven't submitted."
        }
    });

    // this will call before submit; and it will unbind beforeunload
    $(function () {
        $("#createjob").submit(function (event) {
            $(window).unbind("beforeunload");
        });
    });

</script>

How to iterate over a string in C?

Replace sizeof with strlen and it should work.

How to append rows in a pandas dataframe in a for loop?

I have created a data frame in a for loop with the help of a temporary empty data frame. Because for every iteration of for loop, a new data frame will be created thereby overwriting the contents of previous iteration.

Hence I need to move the contents of the data frame to the empty data frame that was created already. It's as simple as that. We just need to use .append function as shown below :

temp_df = pd.DataFrame() #Temporary empty dataframe
for sent in Sentences:
    New_df = pd.DataFrame({'words': sent.words}) #Creates a new dataframe and contains tokenized words of input sentences
    temp_df = temp_df.append(New_df, ignore_index=True) #Moving the contents of newly created dataframe to the temporary dataframe

Outside the for loop, you can copy the contents of the temporary data frame into the master data frame and then delete the temporary data frame if you don't need it

Failed to auto-configure a DataSource: 'spring.datasource.url' is not specified

Since you have added both mongodb and data-jpa dependencies in your pom.xml file, it was creating a dependency conflict like below

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

Try removing jpa dependency and run. It should work fine.

FFMPEG mp4 from http live streaming m3u8 file?

Your command is completely incorrect. The output format is not rawvideo and you don't need the bitstream filter h264_mp4toannexb which is used when you want to convert the h264 contained in an mp4 to the Annex B format used by MPEG-TS for example. What you want to use instead is the aac_adtstoasc for the AAC streams.

ffmpeg -i http://.../playlist.m3u8 -c copy -bsf:a aac_adtstoasc output.mp4

How to store and retrieve a dictionary with redis

you can pickle your dict and save as string.

import pickle
import redis

r = redis.StrictRedis('localhost')
mydict = {1:2,2:3,3:4}
p_mydict = pickle.dumps(mydict)
r.set('mydict',p_mydict)

read_dict = r.get('mydict')
yourdict = pickle.loads(read_dict)

Get and Set Screen Resolution

This code will work perfectly in WPF. You can use it in either page load or in button click.

      string screenWidth =System.Windows.SystemParameters.PrimaryScreenWidth.ToString();

      string screenHeight = System.Windows.SystemParameters.PrimaryScreenHeight.ToString();

      txtResolution.Text ="Resolution : "+screenWidth + " X " + screenHeight;

Git merge reports "Already up-to-date" though there is a difference

I had the same problem. I had changes in the remote and it was still showing "Already up to date". Recloning the repository fixed the problem for me.

Not showing placeholder for input type="date" field

Found a better way to handle user basic comprehension with mouseover and opening datepicker on click :

<input type="text" onfocus="(this.type='date')" onmouseover="(this.type = 'date')" onblur="(this.value ? this.type = 'date' : this.type = 'text')" id="date_start" placeholder="Date">

Also hide webkit arrow and make it 100% wide to cover the click :

input[type="date"] {
    position: relative;
}
input[type="date"]::-webkit-calendar-picker-indicator {
  position: absolute;
  height: 100%;
  width: 100%;
  opacity: 0;
  left: 0;
  right: 0;
  top:0;
  bottom: 0;
}

How do I start/stop IIS Express Server?

to stop IIS manually:

  1. go to start menu
  2. type in IIS

you get a search result for the manager (Internet Information Services (IIS) manager, on the right side of it there are restart/stop/start buttons.

If you don't want IIS to start on startup because its really annoying..:

  1. go to start menu.
  2. click control panel.
  3. click programs.
  4. turn windows features on or off
  5. wait until the list is loaded
  6. search for Internet Information Services (IIS).
  7. uncheck the box.
  8. Wait until it's done with the changes.
  9. restart computer, but then again the info box will tell you to do that anyways (you can leave this for later if you want to).

oh and IIS and xampp basically do the same thing just in a bit different way. ANd if you have Xampp for your projects then its not really all that nessecary to leave it on if you don't ever use it anyways.

JavaFX Application Icon

I used this in my application

Image icon = new Image(getClass().getResourceAsStream("icon.png"));
window.getIcons().add(icon);

Here window is the stage.

What is the fastest way to send 100,000 HTTP requests in Python?

I know this is an old question, but in Python 3.7 you can do this using asyncio and aiohttp.

import asyncio
import aiohttp
from aiohttp import ClientSession, ClientConnectorError

async def fetch_html(url: str, session: ClientSession, **kwargs) -> tuple:
    try:
        resp = await session.request(method="GET", url=url, **kwargs)
    except ClientConnectorError:
        return (url, 404)
    return (url, resp.status)

async def make_requests(urls: set, **kwargs) -> None:
    async with ClientSession() as session:
        tasks = []
        for url in urls:
            tasks.append(
                fetch_html(url=url, session=session, **kwargs)
            )
        results = await asyncio.gather(*tasks)

    for result in results:
        print(f'{result[1]} - {str(result[0])}')

if __name__ == "__main__":
    import pathlib
    import sys

    assert sys.version_info >= (3, 7), "Script requires Python 3.7+."
    here = pathlib.Path(__file__).parent

    with open(here.joinpath("urls.txt")) as infile:
        urls = set(map(str.strip, infile))

    asyncio.run(make_requests(urls=urls))

You can read more about it and see an example here.

Git on Bitbucket: Always asked for password, even after uploading my public SSH key

I cloned the repository with HTTPS URL instead of SSH URL hence even after adding the SSH Key it was asking me for password on Bash Shell.

I just edited the ./.git/config file and changed the value of url variable by simply replacing the https:// to ssh://

E.g.

[core]
        ...
        ...
        ...
[remote "origin"]
        url = https://<username>@bitbucket.org/<username>/<repository_name>.git
        fetch = +refs/heads/*:refs/remotes/origin/*
        ...
        ...
        ...

Changed to:

[core]
        ...
        ...
        ...
[remote "origin"]
        url = ssh://<username>@bitbucket.org/<username>/<repository_name>.git
        fetch = +refs/heads/*:refs/remotes/origin/*
        ...
        ...
        ...

Java 8: Lambda-Streams, Filter by Method with Exception

The functional interfaces in Java don’t declare any checked or unchecked exception. We need to change the signature of the methods from:

boolean isActive() throws IOException; 
String getNumber() throwsIOException;

To:

boolean isActive();
String getNumber();

Or handle it with try-catch block:

public Set<String> getActiveAccountNumbers() {
  Stream<Account> s =  accounts.values().stream();
  s = s.filter(a -> 
    try{
      a.isActive();
    }catch(IOException e){
      throw new RuntimeException(e);
    }
  );
  Stream<String> ss = s.map(a -> 
    try{
      a.getNumber();
    }catch(IOException e){
      throw new RuntimeException(e);
    }
  );
  return ss.collect(Collectors.toSet());
}

Another option is to write a custom wrapper or use a library like ThrowingFunction. With the library we only need to add the dependency to our pom.xml:

<dependency>
    <groupId>pl.touk</groupId>
    <artifactId>throwing-function</artifactId>
    <version>1.3</version>
</dependency>

And use the specific classes like ThrowingFunction, ThrowingConsumer, ThrowingPredicate, ThrowingRunnable, ThrowingSupplier.

At the end the code looks like this:

public Set<String> getActiveAccountNumbers() {
  return accounts.values().stream()
    .filter(ThrowingPredicate.unchecked(Account::isActive))
    .map(ThrowingFunction.unchecked(Account::getNumber))
    .collect(Collectors.toSet());
}

How to stop (and restart) the Rails Server?

In case that doesn't work there is another way that works especially well in Windows: Kill localhost:3000 process from Windows command line