You can cast to void to ignore the return value from the Add method:

    [void]$myArrayList.Add(&quot;test&quot;) 

Another option is to redirect to $null:

    $myArrayList.Add(&quot;test&quot;) &gt; $null

Two more options :)

Pipe to [out-null][1]          

    $myArrayList.Add(&quot;test&quot;) | Out-Null  

Assign the result to $null:    

    $null = $myArrayList.Add(&quot;test&quot;)


  [1]: https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/out-null

I am learning C++, but I am confused about abstract class and concrete class. Some real world examples would be appreciated.

What is the difference between a concrete class and an abstract class?

In a Java method, I&#39;d like to use a Jersey client object to do a POST operation on a RESTful web service (also written using Jersey) but am not sure how to use the client to send the values that will be used as FormParam&#39;s on the server.  I&#39;m able to send query params just fine.



Using the Jersey client to do a POST operation

is there a way to supress the return value (=Index) of an ArrayList
in Powershell (using System.Collections.ArrayList) or should I use
another class?

    $myArrayList = New-Object System.Collections.ArrayList($null)
    $myArrayList.Add(&quot;test&quot;)
    Output: 0

Prevent ArrayList.Add() from returning the index

is there a way to supress the return value (=Index) of an ArrayList
in Powershell (using System.Collections.ArrayList) or should I use
another class?
<pre><code class="hljs language-bash">$myArrayList = New-Object System.Collections.ArrayList($null)
$myArrayList.Add("test")
Output: 0
</code></pre>

The `IDictionary&lt;TKey, TValue&gt;` in .NET 4 / Silverlight 4 does not support covariance, i.e. I can&#39;t do a

    IDictionary&lt;string, object&gt; myDict = new Dictionary&lt;string, string&gt;();

analog to what I can do with `IEnumerable&lt;T&gt;`s now.

Probably boils down to the `KeyValuePair&lt;TKey, TValue&gt;` not being covariant either. I feel that covariance should be allowed in dictionaries at least for the values.

So is that a bug or a feature? Will it ever come, maybe in .NET 37.4?

UPDATE (2 years later):

There will be an [`IReadOnlyDictionary&lt;TKey, TValue&gt;`](http://msdn.microsoft.com/en-us/library/hh136548(v=VS.110).aspx) in .NET 4.5, but it won&#39;t be covariant either `:&#183;/`, because it derives from `IEnumerable&lt;KeyValuePair&lt;TKey, TValue&gt;&gt;`, and `KeyValuePair&lt;TKey, TValue&gt;` is not an interface and thus cannot be covariant.

The BCL team would have to redesign a lot to come up and use some `ICovariantPair&lt;TKey, TValue&gt;` instead. Also strongly-typed indexers &#225; la `this[TKey key]` aren&#39;t possible for covariant interfaces. A similar end can only be achieved by placing an extension method `GetValue&lt;&gt;(this IReadOnlyDictionary&lt;TKey, TValue&gt; self, TKey key)` somewhere which would somehow internally have to call an an actual implementation, which arguably looks like a quite messy approach.

IDictionary&lt;TKey, TValue&gt; in .NET 4 not covariant

I have a WinForms application with `DataGridView` control. My control has five
columns (say &quot;Name&quot;, &quot;Address&quot;, &quot;Phone&quot; etc)

I am not happy with default column width. I want to have more control over column appearance. What I want
is to be able to do one of the following:

 - Set width of each column in percent
 - Set width of each column in pixels
 - Use some other best-practive method (make width to fit text etc)

Please suggest - which property to use and how.



DataGridView - how to set column width?

What is a Singleton and when should I use it?

What is a singleton in C#?

A C# desktop application (on the Visual Studio Express/Community edition) worked, but then it didn&#39;t work 5 seconds later.

I tried the following:

* Ensure debug configuration, debug flag, and full debug information are set on all assemblies.
* Delete all bin and obj folders and all DLL files related to the project from my entire machine.
* Recreate projects causing the problem from scratch.
* Reboot.

I have two Windows Forms projects in the solution. One of them loads the debug information, one doesn&#39;t. They both refer to the assembly I&#39;m trying to get debug information on in exactly the same way in the project file. Any ideas?

----

I want to add here, mostly for myself when I come back to review this question, that symbols are not loaded until the assembly is loaded, and the assembly is not loaded until it is needed. If the breakpoint is in a library that is only used in one function in your main assembly, the symbols will not be loaded (and it will show the breakpoint as not being hit) until that function is called.



How do I remedy &quot;The breakpoint will not currently be hit. No symbols have been loaded for this document.&quot; warning?

I&#39;ve got the lovely task of working out how to handle large files being loaded into our application&#39;s script editor (it&#39;s like [VBA][1] for our internal product for quick macros). Most files are about 300-400&amp;nbsp;KB which is fine loading. But when they go beyond 100&amp;nbsp;MB the process has a hard time (as you&#39;d expect).

What happens is that the file is read and shoved into a RichTextBox which is then navigated - don&#39;t worry too much about this part.

The developer who wrote the initial code is simply using a StreamReader and doing

    [Reader].ReadToEnd()

which could take quite a while to complete.

My task is to break this bit of code up, read it in chunks into a buffer and show a progressbar with an option to cancel it.

Some assumptions:

 - Most files will be 30-40&amp;nbsp;MB
 - The contents of the file is text (not binary), some are Unix format, some are DOS.
 - Once the contents is retrieved we work out what terminator is used.
 - No-one&#39;s concerned once it&#39;s loaded the time it takes to render in the richtextbox. It&#39;s just the initial load of the text.

Now for the questions:

  - Can I simply use StreamReader, then check the Length property (so ProgressMax) and issue a Read for a set buffer size and iterate through in a while loop *WHILST* inside a background worker, so it doesn&#39;t block the main UI thread? Then return the stringbuilder to the main thread once it&#39;s completed.
  - The contents will be going to a StringBuilder. can I initialise the StringBuilder with the size of the stream if the length is available?

Are these (in your professional opinions) good ideas? I&#39;ve had a few issues in the past with reading content from Streams, because it will always miss the last few bytes or something, but I&#39;ll ask another question if this is the case.

  [1]: http://en.wikipedia.org/wiki/Visual_Basic_for_Applications


Reading large text files with streams in C#

What is the &quot;best&quot; way to handle command-line arguments?

It seems like there are several answers on what the &quot;best&quot; way is and as a result I am stuck on how to handle something as simple as:

    script.ps1 /n name /d domain

AND

    script.ps1 /d domain /n name.

Is there a plugin that can handle this better? I know I am reinventing the wheel here.

Obviously what I have already isn&#39;t pretty and surely isn&#39;t the &quot;best&quot;, but it works.. and it is UGLY.

    for ( $i = 0; $i -lt $args.count; $i++ ) {
        if ($args[ $i ] -eq &quot;/n&quot;){ $strName=$args[ $i+1 ]}
        if ($args[ $i ] -eq &quot;-n&quot;){ $strName=$args[ $i+1 ]}
        if ($args[ $i ] -eq &quot;/d&quot;){ $strDomain=$args[ $i+1 ]}
        if ($args[ $i ] -eq &quot;-d&quot;){ $strDomain=$args[ $i+1 ]}
    }
    Write-Host $strName
    Write-Host $strDomain


How to handle command-line arguments in PowerShell

This is the `try catch` in PowerShell 2.0

&lt;!-- language: lang-powershell --&gt;

    $urls = &quot;http://www.google.com&quot;, &quot;http://none.greenjump.nl&quot;, &quot;http://www.nu.nl&quot;
    $wc = New-Object System.Net.WebClient 
    
    foreach($url in $urls)
    {
        try
        {
            $url
            $result=$wc.DownloadString($url)
        }
        catch [System.Net.WebException]
        {
            [void]$fails.Add(&quot;url webfailed $url&quot;)
        }  
    }

but what I want to do is something like in c#

&lt;!-- language: lang-csharp --&gt;

    catch( WebException ex)
    {
        Log(ex.ToString());
    }

Is this possible?

powershell 2.0 try catch how to access the exception

I can format the [`Get-Date`][1] cmdlet no problem like this:

    $date = Get-Date -format &quot;yyyyMMdd&quot;

But once I&#39;ve got [a date][2] in a variable, how do I format it? The statement below

    $dateStr = $date -format &quot;yyyMMdd&quot;

returns this error:

&gt; &quot;You must provide a value expression
&gt; on the right-hand side of the &#39;-f&#39;
&gt; operator&quot;

  [1]: https://technet.microsoft.com/en-us/library/hh849887.aspx
  [2]: https://msdn.microsoft.com/en-us/library/system.datetime%28v=vs.110%29.aspx




How to format a DateTime in PowerShell

In Bash I can easily do something like

    command1 &amp;&amp; command2 || command3

which means to run command1 and if command1 succeeds to run command2 and if command1 fails to run command3.

What&#39;s the equivalent in PowerShell?


What are the PowerShell equivalents of Bash&#39;s &amp;&amp; and || operators?

Is there any way to copy a really large file (from one server to another) in PowerShell AND display its progress?

There are solutions out there to use Write-Progress in conjunction with looping to copy many files and display progress.  However I can&#39;t seem to find anything that would show progress of a single file.

Any thoughts?

Progress during large file copy (Copy-Item &amp; Write-Progress?)

Is `ArrayList` an array or a list in java? what is the time complexity for the get operation, is it `O(n)` or `O(1)`?



Time complexity for java ArrayList

    ArrayList&lt;MyClass&gt; myList = new ArrayList&lt;MyClass&gt;();
    
    ListView listView = (ListView) findViewById(R.id.list);
    
    ArrayAdapter&lt;MyClass&gt; adapter = new ArrayAdapter&lt;MyClass&gt;(this, R.layout.row,
        to, myList.);
    listView.setAdapter(adapter);

Class: MyClass
----------------


    class MyClass {
        public String reason;
        public long long_val;
    }

I have created row.xml in layouts, but don&#39;t know how to show both reason and long_val in the ListView using ArrayAdapter.



How to use ArrayAdapter&lt;myClass&gt;

Does anyone have any idea, *why* removeRange method in [AbstractList](http://java.sun.com/javase/6/docs/api/java/util/AbstractList.html) (and also in [ArrayList](http://java.sun.com/j2se/1.5.0/docs/api/java/util/ArrayList.html)) is `protected`?  It looks like a quite well-defined and useful operation, but still, to use it, we&#39;re forced to subclass the List implementation.

Is there some hidden rationale? Seems quite inexplicable to me.

Why is Java&#39;s AbstractList&#39;s removeRange() method protected?

What is the difference between `ArrayList` and `List&lt;&gt;` in C#? 

Is it only that `List&lt;&gt;` has a type while `ArrayList` doesn&#39;t?

ArrayList vs List&lt;&gt; in C#

In Java, how can you make an `ArrayList` read-only (so that no one can add elements, edit, or delete elements) after initialization?

Content Type	Original Author	Original Content on Stackoverflow
Question	Milde	View Question on Stackoverflow
Solution 1 - .Net	Keith Hill	View Answer on Stackoverflow
Solution 2 - .Net	Shay Levy	View Answer on Stackoverflow

Prevent ArrayList.Add() from returning the index

.Net Problem Overview

.Net Solutions

Solution 1 - .Net

Solution 2 - .Net

Using the Jersey client to do a POST operation

What is the difference between a concrete class and an abstract class?

Attributions