Yes; just uses braces instead of parentheses.

    var nvc = new NameValueCollection { {&quot;a&quot;, &quot;1&quot;}, {&quot;b&quot;, &quot;2&quot;} };


You can call `Add` methods with arbitrary sets of parameters using the syntax.

You can use collection initializers with everything that has `Add` method. Yeah, duck typing. If `Add` has more then 1 param put tuples in curly bracets:

    NameValueCollection nvc = new NameValueCollection() { { &quot;a&quot;, &quot;1&quot; }, { &quot;b&quot;, &quot;2&quot; } };

I check to see if a file exists with 

    if(!File.Exists(myPath))
    {
        File.Create(myPath);
    }

However, when I go to create a `StreamReader` with this newly created file, I get an error saying that

&gt;The process cannot access the file &#39;[my file path here]&#39; because it is being used by another process.

There isn&#39;t a `File.Close(myPath)` that I can call so that it is closed after being created, so how do I free this resource so that I can open it later in my program?

Closing a file after File.Create

I think the question is clear enough. Will the `auto` keyword auto-detect const-ness, or always return a non-const type, even if there are eg. two versions of a function (one that returns `const` and the other that doesn&#39;t).

Just for the record, I do use `const auto end = some_container.end()` before my for-loops, but I don&#39;t know if this is necessary or even different from normal `auto`.

does `const auto` have any meaning?

Is there a way to initialize a NVC using C# collection initializer syntax:

    NameValueCollection nvc = new NameValueCollection() { (&quot;a&quot;, &quot;1&quot;), (&quot;b&quot;, &quot;2&quot;) };

Thanks



Can I use collection initializers with a NameValueCollection?

Is there a way to initialize a NVC using C# collection initializer syntax:
<pre><code class="hljs language-ini">NameValueCollection nvc = new NameValueCollection() { ("a", "1"), ("b", "2") };
</code></pre>
Thanks

Whenever I look deeply enough into reflector I bump into `extern` methods with no source.  I read the msdn documentation at http://msdn.microsoft.com/en-us/library/e59b22c5(v=vs.80).aspx.  What I got from that article is that methods with the `extern` modifier have to be injected.  I interpreted this to mean it works something like an abstract factory pattern.  I also noticed that I&#39;ve never seen a non-static extern method.  Is static declaration a requirement (I could see how this would make sense)?   I&#39;m still guessing here and I&#39;m not sure how it actually works.  It seems to me like the compiler must recognize certain attributes that mitigate processing, but I don&#39;t know what the attributes are other than ones I&#39;ve come across like `MethodImplAttribute` and `DllImportAttribute` from the MSDN example.  How does someone leverage the `extern` attribute?  It said that in many instances this can increase performance.  Also, how would I go about looking into the source of `extern` methods like `Object.InternalGetEquals()`? 

How does extern work in C#?

Using dynamic pattern perhaps? You can call any method/property using the dynamic keyword, right? How to check whether the method exist before calling myDynamicObject.DoStuff(), for example?

How to check whether an object has certain method/property?

I am using the Open XML SDK to open an Excel xlsx file and I try to read the cellvalue on position A1 in each sheet.
I use the following code:

    using (SpreadsheetDocument spreadsheetDocument = SpreadsheetDocument.Open(openFileDialog1.FileName, false))
    {
        var sheets = spreadsheetDocument.WorkbookPart.Workbook.Descendants&lt;Sheet&gt;();

        foreach (Sheet sheet in sheets)
        {
            WorksheetPart worksheetPart = (WorksheetPart)spreadsheetDocument.WorkbookPart.GetPartById(sheet.Id);
            Worksheet worksheet = worksheetPart.Worksheet;

            Cell cell = GetCell(worksheet, &quot;A&quot;, 1);

            Console.Writeline(cell.CellValue.Text);
         }
    }

    private static Cell GetCell(Worksheet worksheet, string columnName, uint rowIndex)
    {
         Row row = GetRow(worksheet, rowIndex);

         if (row == null)
             return null;

         return row.Elements&lt;Cell&gt;().Where(c =&gt; string.Compare
                   (c.CellReference.Value, columnName +
                   rowIndex, true) == 0).First();
    }

    // Given a worksheet and a row index, return the row.
    private static Row GetRow(Worksheet worksheet, uint rowIndex)
    {
        return worksheet.GetFirstChild&lt;SheetData&gt;().
              Elements&lt;Row&gt;().Where(r =&gt; r.RowIndex == rowIndex).First();
    } 

The text in the first worksheet on position A1 is simply &#39;test&#39; however, in my console I see the value &#39;0&#39; as cell.CellValue.Text

Does anyone have an idea to get the correct value of the cell?

OpenXML SDK returning a number for CellValue instead of cells text

I know it&#39;s possible to cast a list of items from one type to another (given that your object has a public static explicit operator method to do the casting) one at a time as follows:

    List&lt;Y&gt; ListOfY = new List&lt;Y&gt;();
    
    foreach(X x in ListOfX)
        ListOfY.Add((Y)x);

But is it not possible to cast the entire list at one time? For example,

    ListOfY = (List&lt;Y&gt;)ListOfX;

Shorter syntax for casting from a List&lt;X&gt; to a List&lt;Y&gt;?

How do I determine what platform my C# code is running on? for example whether it is running on Linux or windows so that I can execute different code at runtime.

I have a C# Windows application that I want to build to target Windows and Linux platforms.

So far I have created two project files pointing to the same set of source code files. I then use a conditional compilation statement one of the projects called *LINUX*.

Where there are difference in the actual code I use conditional statements using the conditional compilation statement, for example,

    #if (LINUX)
        &#39; Do something
    #endif

Is there a better way of doing this? I don&#39;t really want to have two project files.






How to check the OS version at runtime, e.g. on Windows or Linux, without using a conditional compilation statement

*Note: This is an FAQ, asked specifically so I can answer it myself, as this issue seems to come up fairly often and I want to put it in a location where it can (hopefully) be easily found via a search*

As prompted by a comment on my [answer here](https://stackoverflow.com/questions/5189984/why-cant-this-simple-scala-example-be-compiled/5190950#5190950)

---
For example:

    &quot;abcde&quot; map {_.toUpperCase} //returns a String
    &quot;abcde&quot; map {_.toInt} // returns an IndexedSeq[Int]
    BitSet(1,2,3,4) map {2*} // returns a BitSet
    BitSet(1,2,3,4) map {_.toString} // returns a Set[String]

Looking in the scaladoc, all of these use the `map` operation inherited from `TraversableLike`, so how come it&#39;s always able to return the most specific valid collection? Even `String`, which provides `map` via an implicit conversion.

How are Scala collections able to return the correct collection type from a map operation?

I have an array of objects and I want to concatenate it with another array of objects, except that objects that have same id&#39;s. That objects are used in many places in the system and don&#39;t have hash code or equals implemented. So I don&#39;t want to implement `hashCode()` and `equals()`, cause I&#39;m afraid to break something somewhere in the system where that objects are used and I don&#39;t know about that. 

I want to put all that objects in a set, but somehow make the objects use custom `hashCode()` and `equals()`. Something like custom `Comparator`, but for equals.

Is it possible in java make something like Comparator but for implementing custom equals() and hashCode()

Is it possible to define a list with a fixed size that&#39;s 100? If not why isn&#39;t this available in Java?

Define a fixed-size list in Java

Why does Python not support a record type natively? It&#39;s a matter of having a mutable version of namedtuple.

I could use `namedtuple._replace`. But I need to have these records in a collection and since `namedtuple._replace` creates another instance, I also need to modify the collection which becomes messy quickly. 

Background:
I have a device whose attributes I need to get by polling it over TCP/IP. i.e. its representation is a mutable object.

Edit:
I have a set of devices for whom I need to poll.

Edit:
I need to iterate through the object displaying its attributes using PyQt. I know I can add special methods like `__getitem__` and `__iter__`, but I want to know if there is an easier way.

Edit:
I would prefer a type whose attribute are fixed (just like they are in my device), but are mutable.

Why does Python not support record type? (i.e. mutable namedtuple)

Today I was happily coding away when I got to a piece of code I already used hundreds of times:

&gt; Iterating through a Collection (here ArrayList)

For some reason, I actually looked at the autocompletion options of Eclipse and it got me wondering:

**What cases are the following loops better to use than the others?**

The classic array index loop:

    for (int i = 0; i &lt; collection.length; i++) {
	  type array_element = collection.get(index);
	}

The Iterator hasNext()/next():

	for (Iterator iterator = collection.iterator(); iterator.hasNext();) {
	  type type = (type) iterator.next();	
	}

And my favorite because its so simple to write:		

	for (iterable_type iterable_element : collection) {
			
	}

Content Type	Original Author	Original Content on Stackoverflow
Question	gap	View Question on Stackoverflow
Solution 1 - C#	SLaks	View Answer on Stackoverflow
Solution 2 - C#	Andrey	View Answer on Stackoverflow

Can I use collection initializers with a NameValueCollection?

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

does `const auto` have any meaning?

Closing a file after File.Create

Attributions