What is VB&#39;s equivalent for C#&#39;s `default(T)` - the [default operator][1]


  [1]: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/default

VB equivalent for C#&#39;s default(T)

The Entity Framework context object implements a Dispose() method which &quot;Releases the resources used by the object context&quot;. What does it do really? Could it be a bad thing to always put it into a using {} statement? I&#39;ve seen it being used both with and without the using statement.

I&#39;m specifically going to use the EF context from within a WCF service method, create the context, do some linq and return the answer.

**EDIT:** Seems that I&#39;m not the only one wondering about this. Another question is what&#39;s really happening inside the Dispose() method. Some say it closes connections, and some articles says not. What&#39;s the deal?

Should Entity Framework Context be Put into Using Statement?

How do you replace all instances of one string with another in javascript?
Example:

    someString = &#39;the cat looks like a cat&#39;
    anotherString = someString.replace(&#39;cat&#39;, &#39;dog&#39;);

results in anotherString being set to &#39;the **dog** looks like a **cat**&#39;, and I would like it to be &#39;the **dog** looks like a **dog**&#39;

Javascript multiple replace

How do you replace all instances of one string with another in javascript?
Example:
<pre><code class="hljs language-ini">someString = 'the cat looks like a cat'
anotherString = someString.replace('cat', 'dog');
</code></pre>
results in anotherString being set to 'the dog looks like a cat', and I would like it to be 'the dog looks like a dog'

I’m embedding Google Maps into my web site. Once Google Maps is loaded, I need to kick off a few JavaScript processes.

**Is there a way to auto-detect when Google Maps has fully loaded, including tile downloads and all?**

A `tilesloaded()` method exists that is supposed to accomplish exactly this task but [it does not work](https://www.google.com/search?hl=en&amp;q=GEvent.addListener%28map,+%22tilesloaded%22,+function%28%29+&amp;#123;&amp;btnG=Google+Search&amp;aq=f&amp;oq=).

How can I check whether Google Maps is fully loaded?

I&#39;m trying to scroll down 100px every time the user gets near the top of the document.

I have the function executing when the user gets close to the top of the document, but the .scrollTo function isn&#39;t working.

I put an alert after and before to check to see if it actually was the line or not that was stopping it and only the first alert goes off, here&#39;s the code:

    alert(&quot;starting&quot;);
    $.scrollTo({ top: &#39;+=100px&#39;, left: &#39;+=0px&#39; }, 800);
    alert(&quot;finished&quot;);

I know I have the jquery page linked properly because I&#39;m using many other jquery functions throughout and they all work fine. I&#39;ve also tried removing the &#39;px&#39; from above and it doesn&#39;t seem to make a difference.

How to scroll the window using JQuery $.scrollTo() function

Can anyone tell me what is going wrong with this code? I tried to submit a form with JavaScript, but an error &quot;.submit is not a function&quot; shown. See below for more details of the code:

    &lt;form action=&quot;product.php&quot; method=&quot;get&quot; name=&quot;frmProduct&quot; id=&quot;frmProduct&quot; enctype=&quot;multipart/form-data&quot;&gt;

    &lt;input onclick=&quot;submitAction()&quot; id=&quot;submit_value&quot; type=&quot;button&quot; name=&quot;submit_value&quot; value=&quot;&quot;&gt;

    &lt;/form&gt;

    &lt;script type=&quot;text/javascript&quot;&gt;
        function submitAction()
        {
            document.frmProduct.submit();
        }
    &lt;/script&gt;

I also tried this:

    &lt;script type=&quot;text/javascript&quot;&gt;
        function submitAction()
        {
            document.forms[&quot;frmProduct&quot;].submit();
        }
    &lt;/script&gt;

Both show me the same error  :(








&quot;Submit is not a function&quot; error in JavaScript

I have created a custom URL protocol handler.

`http://`

`mailto://`

**`custom://`**

I have registered a WinForms application to respond accordingly. This all works great.

But I would like to be able to gracefully handle the case where the user doesn&#39;t have the custom URL protocol handler installed, yet.

In order to be able to do this I need to be able to detect the browser&#39;s registered protocol handlers, I would assume from JavaScript. But I have been unable to find a way to poll for the information. I am hoping to find a solution to this problem.

Thanks for any ideas you might be able to share.





How to detect browser&#39;s protocol handlers?

I need to check a JavaScript array to see if there are any duplicate values. What&#39;s the easiest way to do this? I just need to find what the duplicated values are - I don&#39;t actually need their indexes or how many times they are duplicated.

I know I can loop through the array and check all the other values for a match, but it seems like there should be an easier way.

### Similar question: 

 - https://stackoverflow.com/questions/1960473

Get all non-unique values (i.e.: duplicate/more than one occurrence) in an array

Why do Javascript sub-matches stop working when the `g` modifier is set?

    var text = &#39;test test test test&#39;;
    
    var result = text.match(/t(e)(s)t/);
    // Result: [&quot;test&quot;, &quot;e&quot;, &quot;s&quot;]

The above works fine, `result[1]` is `&quot;e&quot;` and `result[2]` is `&quot;s&quot;`.

    var result = text.match(/t(e)(s)t/g);
    // Result: [&quot;test&quot;, &quot;test&quot;, &quot;test&quot;, &quot;test&quot;]

The above ignores my capturing groups. Is the following the only valid solution?

    var result = text.match(/test/g);
    for (var i in result) {
        console.log(result[i].match(/t(e)(s)t/));
    }
    /* Result:
    [&quot;test&quot;, &quot;e&quot;, &quot;s&quot;]
    [&quot;test&quot;, &quot;e&quot;, &quot;s&quot;]
    [&quot;test&quot;, &quot;e&quot;, &quot;s&quot;]
    [&quot;test&quot;, &quot;e&quot;, &quot;s&quot;]
    */

**EDIT:**

I am back again to happily tell you that 10 years later you can now do this (.matchAll has been added to the spec)

    let result = [...text.matchAll(/t(e)(s)t/g)];



JavaScript regular expressions and sub-matches

I need a regular expression that I can use in VBScript and .NET that will return only the numbers that are found in a string. 

For Example any of the following &quot;strings&quot; should return only **1231231234**

- 123 123 1234
- (123) 123-1234
- 123-123-1234
- (123)123-1234
- 123.123.1234
- 123  123 1234
- 1 2 3 1 2 3 1 2 3 4

This will be used in an email parser to find telephone numbers that customers may provide in the email and do a database search.

I may have missed a similar regex but I did search on regexlib.com.

[EDIT] - Added code generated by [RegexBuddy][1] after setting up musicfreak&#39;s answer

**VBScript Code**

    Dim myRegExp, ResultString
    Set myRegExp = New RegExp
    myRegExp.Global = True
    myRegExp.Pattern = &quot;[^\d]&quot;
    ResultString = myRegExp.Replace(SubjectString, &quot;&quot;)

**VB.NET**

    Dim ResultString As String
    Try
          Dim RegexObj As New Regex(&quot;[^\d]&quot;)
          ResultString = RegexObj.Replace(SubjectString, &quot;&quot;)
    Catch ex As ArgumentException
          &#39;Syntax error in the regular expression
    End Try

**C#**

    string resultString = null;
    try {
    	Regex regexObj = new Regex(@&quot;[^\d]&quot;);
    	resultString = regexObj.Replace(subjectString, &quot;&quot;);
    } catch (ArgumentException ex) {
    	// Syntax error in the regular expression
    }


  [1]: http://www.regexbuddy.com/

return only Digits 0-9 from a String

I&#39;ve found a solution for finding the position of an underscore with PATINDEX :

    DECLARE @a VARCHAR(10)  
    SET     @a = &#39;37_21&#39;
    
    PRINT PATINDEX(&#39;%_%&#39;, @a)                    -- return 1 (false)
    PRINT PATINDEX(&#39;%!%&#39;, REPLACE(@a, &#39;_&#39;, &#39;!&#39;)) -- return 3 (correct)

Have you other ideas? Like a way to escape the underscore character?  


How to escape underscore character in PATINDEX pattern argument?

I&#39;m trying to get the elements in an HTML doc that contain the following pattern of text: #\S{11}

    &lt;h2&gt; this is cool #12345678901 &lt;/h2&gt;

So, the previous would match by using:

    soup(&#39;h2&#39;,text=re.compile(r&#39; #\S{11}&#39;))

And the results would be something like:

    [u&#39;blahblah #223409823523&#39;, u&#39;thisisinteresting #293845023984&#39;]

I&#39;m able to get all the text that matches (see line above). But I want the parent element of the text to match, so I can use that as a starting point for traversing the document tree. In this case, I&#39;d want all the h2 elements to return, not the text matches.

Ideas?

Using BeautifulSoup to find a HTML tag that contains certain text

After collecting user input for various conditions like

 1. Starts with : `/(^@)/`
 2. Ends with : `/(@$)/`
 3. Contains : `/@/`
 4. Doesn&#39;t contains

To make single regex if user enter multiple conditions,
I combine them with `&quot;|&quot;` so if 1 and 2 given it become `/(^@)|(@$)/`

This method works so far but,

I&#39;m not able to determine correctly, What should be the regex for the 4th condition? And combining regex this way work?


----------


&gt; Update: @(user input) won&#39;t be same
&gt; for two conditions and not all four
&gt; conditions always present but they can
&gt; be and in future I might need more
&gt; conditions like &quot;is exactly&quot; and &quot;is
&gt; exactly not&quot; etc. so, I&#39;m more curious
&gt; to know this approach will scale ?
&gt; 
&gt; Also there may be issues of user input
&gt; cleanup so regex escaped properly, but
&gt; that is ignored right now.

Combine Regexp?

How can I write two functions that would take a string and return if it starts with the specified character/string or ends with it?

For example:

    $str = &#39;|apples}&#39;;
    
    echo startsWith($str, &#39;|&#39;); //Returns true
    echo endsWith($str, &#39;}&#39;); //Returns true


startsWith() and endsWith() functions in PHP

I have a `String` that I want to use as an `InputStream`. In Java 1.0, you could use [`java.io.StringBufferInputStream`][1], but that has been `@Deprecrated` (with good reason--you cannot specify the character set encoding):

&gt; This class does not properly convert
&gt; characters into bytes. As of JDK 1.1,
&gt; the preferred way to create a stream
&gt; from a string is via the `StringReader`
&gt; class.

You can create a [`java.io.Reader`][2] with [`java.io.StringReader`][3], but there are no adapters to take a `Reader` and create an `InputStream`.

I found an [ancient bug][4] asking for a suitable replacement, but no such thing exists--as far as I can tell.

The oft-suggested workaround is to use [`java.lang.String.getBytes()`][5] as input to [`java.io.ByteArrayInputStream`][6]:

    public InputStream createInputStream(String s, String charset)
        throws java.io.UnsupportedEncodingException {

        return new ByteArrayInputStream(s.getBytes(charset));
    }

but that means materializing the entire `String` in memory as an array of bytes, and defeats the purpose of a stream. In most cases this is not a big deal, but I was looking for something that would preserve the intent of a stream--that as little of the data as possible is (re)materialized in memory.


  [1]: http://java.sun.com/javase/6/docs/api/java/io/StringBufferInputStream.html
  [2]: http://java.sun.com/javase/6/docs/api/java/io/Reader.html
  [3]: http://java.sun.com/javase/6/docs/api/java/io/StringReader.html
  [4]: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4217782
  [5]: http://java.sun.com/javase/6/docs/api/java/lang/String.html#getBytes(java.lang.String)
  [6]: http://java.sun.com/javase/6/docs/api/java/io/ByteArrayInputStream.html

How can I get a java.io.InputStream from a java.lang.String?

How would you normalize all new-line sequences in a string to one type?

I&#39;m looking to make them all CRLF for the purpose of email (MIME documents).  Ideally this would be wrapped in a static method, executing very quickly, and not using regular expressions (since the variances of line breaks, carriage returns, etc. are limited).  Perhaps there&#39;s even a BCL method I&#39;ve overlooked?

ASSUMPTION: After giving this a bit more thought, I think it&#39;s a safe assumption to say that CR&#39;s are either stand-alone or part of the CRLF sequence.  That is, if you see CRLF then you know all CR&#39;s can be removed.  Otherwise it&#39;s difficult to tell how many lines should come out of something like &quot;\r\n\n\r&quot;.

What is a quick way to force CRLF in C# / .NET?

I have this code;

    using System;

    namespace Rapido
    {
        class Constants
        {
            public static const string FrameworkName = &quot;Rapido Framework&quot;;
        }  
    }

Visual Studio tells me: `The constant &#39;Rapido.Constants.FrameworkName&#39; cannot be marked static`

How can I make this constant available from other classes without having to create a new instance of it? (ie. directly accessing it via `Rapido.Constants.FrameworkName`)

Static Constants in C#

Let&#39;s suppose that have a stream of text (or Reader in Java) that I&#39;d like to check for a particular string. The stream of text might be very large so as soon as the search string is found I&#39;d like to return true and also try to avoid storing the entire input in memory.

Naively, I might try to do something like this (in Java):

    public boolean streamContainsString(Reader reader, String searchString) throws IOException {
        char[] buffer = new char[1024];
        int numCharsRead;
        while((numCharsRead = reader.read(buffer)) &gt; 0) {
            if ((new String(buffer, 0, numCharsRead)).indexOf(searchString) &gt;= 0)
                return true;
        }
        return false;
    }

Of course this fails to detect the given search string if it occurs on the boundary of the 1k buffer:

Search text: &quot;stackoverflow&quot;&lt;br&gt;
Stream buffer 1: &quot;abc.........stack&quot;&lt;br&gt;
Stream buffer 2: &quot;overflow.......xyz&quot;&lt;br&gt;

How can I modify this code so that it correctly finds the given search string across the boundary of the buffer but without loading the entire stream into memory?

**Edit:** Note when searching a stream for a string, we&#39;re trying to **minimise the number of reads from the stream** (to avoid latency in a network/disk) and to **keep memory usage constant** regardless of the amount of data in the stream. Actual efficiency of the [string matching algorithm][1] is secondary but obviously, it would be nice to find a solution that used one of the more efficient of those algorithms.


  [1]: http://en.wikipedia.org/wiki/String_searching_algorithm

Efficient way to search a stream for a string

I have a string. How do I remove all text after a certain character? (*In this case `...`*) &lt;br/&gt;
The text after will **`...`** change so I that&#39;s why I want to remove all characters after a certain one.

How to remove all characters after a specific character in python?

I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:

     //...
     Pattern p = Pattern.compile(&quot;(\\d).*(\\d)&quot;);
        String input = &quot;6 example input 4&quot;;
        Matcher m = p.matcher(input);
        if (m.find()) {

            //Now I want replace group one ( (\\d) ) with number 
           //and group two (too (\\d) ) with 1, but I don&#39;t know how.

        }
     



Can I replace groups in Java regex?

I have this string in my JavaScript code:

    &quot;Test abc test test abc test test test abc test test abc&quot;

Doing:

    str = str.replace(&#39;abc&#39;, &#39;&#39;);

Seems to only remove the first occurrence of `abc` in the string above.

How can I replace **all** occurrences of it?







How to replace all occurrences of a string in JavaScript

Given this function:

    function Repeater(template) {
    
        var repeater = {
    
            markup: template,
    
            replace: function(pattern, value) {
                this.markup = this.markup.replace(pattern, value);
            }
    
        };
    
        return repeater;
    
    };

How do I make `this.markup.replace()` replace globally? Here&#39;s the problem. If I use it like this:

    alert(new Repeater(&quot;$TEST_ONE $TEST_ONE&quot;).replace(&quot;$TEST_ONE&quot;, &quot;foobar&quot;).markup);

The alert&#39;s value is &quot;foobar $TEST_ONE&quot;.

If I change `Repeater` to the following, then nothing in replaced in Chrome:

    function Repeater(template) {
    
        var repeater = {
    
            markup: template,
    
            replace: function(pattern, value) {
                this.markup = this.markup.replace(new RegExp(pattern, &quot;gm&quot;), value);
            }
    
        };
    
        return repeater;
    
    };

...and the alert is `$TEST_ONE $TEST_ONE`.

JavaScript replace/regex

Using Java, I want to go through the lines of a text and replace all ampersand symbols (`&amp;`) with the XML entity reference `&amp;amp;`.

I scan the lines of the text and then each word in the text with the Scanner class. Then I use the `CharacterIterator` to iterate over each characters of the word.  However, how can I replace the character?  First, Strings are immutable objects.  Second, I want to replace a character (`&amp;`) with several characters(`amp&amp;;`).  How should I approach this?

    CharacterIterator it = new StringCharacterIterator(token);
    for(char ch = it.first(); ch != CharacterIterator.DONE; ch = it.next()) {
           if(ch == &#39;&amp;&#39;) {
    						    	   
           }
    }

Javascript multiple replace

Javascript Problem Overview

Javascript Solutions

Should Entity Framework Context be Put into Using Statement?

VB equivalent for C#'s default(T)

Attributions