It is possible to do this, you&#39;ve just got the syntax slightly wrong. You need a [`where`][1] for each constraint rather than separating them with a comma:

    public TResponse Call&lt;TResponse, TRequest&gt;(TRequest request)
        where TRequest : MyClass
        where TResponse : MyOtherClass


  [1]: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/where-generic-type-constraint &quot;Microsoft Docs | where constraint&quot;

In addition to the main answer by @LukeH with another usage, we can use multiple interfaces instead of class. (One class and n count interfaces) like this

    public TResponse Call&lt;TResponse, TRequest&gt;(TRequest request)
      where TRequest : MyClass, IMyOtherClass, IMyAnotherClass

or

    public TResponse Call&lt;TResponse, TRequest&gt;(TRequest request)
      where TRequest : IMyClass,IMyOtherClass

In addition to the main answer by @LukeH, I have issue with dependency injection, and it took me some time to fix this. It is worth to share, for those who face the same issue:

    public interface IBaseSupervisor&lt;TEntity, TViewModel&gt; 
        where TEntity : class
        where TViewModel : class

It is solved this way. in containers/services the key is typeof and the comma (,)

    services.AddScoped(typeof(IBaseSupervisor&lt;,&gt;), typeof(BaseSupervisor&lt;,&gt;));

This was mentioned in this [answer][1].


  [1]: https://stackoverflow.com/questions/43087821/how-to-add-a-generic-dependency-injection/43094684#43094684

Each constraint need to be on own line and if there are more of them for single generic parameter then they need to separated by comma.

```
public TResponse Call&lt;TResponse, TRequest&gt;(TRequest request)
    where TRequest : MyClass 
    where TResponse : MyOtherClass, IOtherClass

````
Edited as per comment

I am creating an element with document.createElement().
Now how can I pass it to a function that only takes a Jquery object?

    $(&quot;#id&quot;) 

I can not use it, as the element has not been rendered in the page yet.

How can I convert a DOM element to a jQuery element?

When I&#39;m opening a new file in Vim and I use tab completion, it completes the whole file name instead of doing the partial match like Bash does. Is there an option to make this file name tab completion work more like Bash?


How do I make Vim do normal (Bash-like) tab completion for file names?

I have a generic method which has two generic parameters. I tried to compile the code below but it doesn&#39;t work. Is it a .NET limitation? Is it possible to have multiple constraints for different parameter?

    public TResponse Call&lt;TResponse, TRequest&gt;(TRequest request)
      where TRequest : MyClass, TResponse : MyOtherClass


Generic method with multiple constraints

I have a generic method which has two generic parameters. I tried to compile the code below but it doesn't work. Is it a .NET limitation? Is it possible to have multiple constraints for different parameter?
<pre><code class="hljs language-vbnet">public TResponse Call&#x3C;TResponse, TRequest>(TRequest request)
 where TRequest : MyClass, TResponse : MyOtherClass
</code></pre>

I want to parse SQL code using C#.

Specifically, is there any freely available parser which can parse SQL code and generate a tree or any other structure out of it? It should also generate the proper tree for nested structures.

It should also return which kind of statement the node of this tree represents.

For example, if the node contains a loop condition then it should return that this is a &quot;loop type&quot; of a node.

Or is there any way by which I can parse the code in C# and generate a tree of the type I want?


Parsing SQL code in C#

In a c# threading app, if I were to lock an object, let us say a queue, and if an exception occurs, will the object stay locked?  Here is the pseudo-code:

    int ii;
    lock(MyQueue)
    {
       MyClass LclClass = (MyClass)MyQueue.Dequeue();
       try
       {
          ii = int.parse(LclClass.SomeString);
       }
       catch
       {
         MessageBox.Show(&quot;Error parsing string&quot;);
       }
    }

As I understand it, code after the catch doesn&#39;t execute - but I have been wondering if the lock will be freed.    
   

Does a locked object stay locked if an exception occurs inside it?

My Map is:

    routes.MapRoute(
       &quot;Default&quot;,                                             // Route name
       &quot;{controller}/{action}/{id}&quot;,                          // URL with params
       new { controller = &quot;Home&quot;, action = &quot;Index&quot;, id = &quot;&quot; } // Param defaults
    );

If I use the URL `http://localhost:5000/Home/About/100%2f200` there is no matching route.
I change the URL to `http://localhost:5000/Home/About/100` then the route is matched again.

Is there any easy way to work with parameters that contain slashes? Other escaped values (space `%20`) seem to work.

EDIT:

To encode Base64 works for me. It makes the URL ugly, but that&#39;s OK for now.




    public class UrlEncoder
    { 
        public string URLDecode(string  decode)
        {
            if (decode == null) return null;
            if (decode.StartsWith(&quot;=&quot;))
            {
                return FromBase64(decode.TrimStart(&#39;=&#39;));
            }
            else
            {
                return HttpUtility.UrlDecode( decode) ;
            }
        }

        public string UrlEncode(string encode)
        {
            if (encode == null) return null;
            string encoded = HttpUtility.PathEncode(encode);
            if (encoded.Replace(&quot;%20&quot;, &quot;&quot;) == encode.Replace(&quot; &quot;, &quot;&quot;))
            {
                return encoded;
            }
            else
            {
                return &quot;=&quot; + ToBase64(encode);
            }
        }

        public string ToBase64(string encode)
        {
            Byte[] btByteArray = null;
            UTF8Encoding encoding = new UTF8Encoding();
            btByteArray = encoding.GetBytes(encode);
            string sResult = System.Convert.ToBase64String(btByteArray, 0, btByteArray.Length);
            sResult = sResult.Replace(&quot;+&quot;, &quot;-&quot;).Replace(&quot;/&quot;, &quot;_&quot;);
            return sResult;
        }

        public string FromBase64(string decode)
        {
            decode = decode.Replace(&quot;-&quot;, &quot;+&quot;).Replace(&quot;_&quot;, &quot;/&quot;);
            UTF8Encoding encoding = new UTF8Encoding();
            return encoding.GetString(Convert.FromBase64String(decode));
        }
    }

EDIT1:

At the end it turned out that the best way was to save a nicely formated string for each item I need to select. Thats much better because now I only encode values and never decode them. All special characters become &quot;-&quot;. A lot of my db-tables now have this additional column &quot;URL&quot;. The data is pretty stable, thats why I can go this way. I can even check, if the data in &quot;URL&quot; is unique.

EDIT2:

Also watch out for space character. It looks ok on VS integrated webserver but is different on iis7 [https://stackoverflow.com/questions/1651711/properly-url-encode-space-character][1]


  [1]: https://stackoverflow.com/questions/1651711/properly-url-encode-space-character

URL-encoded slash in URL

I can&#39;t think of an easy one or two liner that would get the previous months first day and last day.

I am LINQ-ifying a survey web app, and they squeezed a new requirement in.

The survey must include all of the service requests for the previous month.  So if it is April 15th, I need all of Marches request ids.

    var RequestIds = (from r in rdc.request 
                      where r.dteCreated &gt;= LastMonthsFirstDate &amp;&amp; 
                      r.dteCreated &lt;= LastMonthsLastDate 
                      select r.intRequestId);

I just can&#39;t think of the dates easily without a switch.  Unless I&#39;m blind and overlooking an internal method of doing it.

Get the previous month&#39;s first and last day dates in c#

I&#39;m using the code below to read a text file that contains foreign characters, the file is encoded ANSI and looks fine in notepad. The code below doesn&#39;t work, when the file values are read and shown in the datagrid the characters appear as squares, could there be another problem elsewhere?

    StreamReader reader = new StreamReader(inputFilePath, System.Text.Encoding.ANSI);
    using (reader = File.OpenText(inputFilePath))

Thanks

**Update 1**: I have tried all encodings found under `System.Text.Encoding`. and all fail to show the file correctly.

**Update 2**: I&#39;ve changed the file encoding (resaved the file) to unicode and used `System.Text.Encoding.Unicode` and it worked just fine. So why did notepad read it correctly? And why didn&#39;t `System.Text.Encoding.Unicode` read the ANSI file?

C# Help reading foreign characters using StreamReader

In C# 3.0 you can create anonymous class with the following syntax

    var o = new { Id = 1, Name = &quot;Foo&quot; };

Is there a way to add these anonymous class to a generic list?

Example:

    var o = new { Id = 1, Name = &quot;Foo&quot; };
    var o1 = new { Id = 2, Name = &quot;Bar&quot; };
    
    List&lt;var&gt; list = new List&lt;var&gt;();
    list.Add(o);
    list.Add(o1);

Another Example:

    List&lt;var&gt; list = new List&lt;var&gt;();

    while (....)
    {
        ....
        list.Add(new {Id = x, Name = y});
        ....
    }

A generic list of anonymous class

I have used the &quot;select&quot; keyword and extension method to return an `IEnumerable&lt;T&gt;` with LINQ, but I have a need to return a generic `Dictionary&lt;T1, T2&gt;` and can&#39;t figure it out.  The example I learned this from used something in a form similar to the following: 

    IEnumerable&lt;T&gt; coll = from x in y 
        select new SomeClass{ prop1 = value1, prop2 = value2 };

I&#39;ve also done the same thing with extension methods.  I assumed that since the items in a  `Dictionary&lt;T1, T2&gt;` can be iterated as `KeyValuePair&lt;T1, T2&gt;` that I could just replace &quot;SomeClass&quot; in the above example with &quot;`new KeyValuePair&lt;T1, T2&gt; { ...`&quot;, but that didn&#39;t work (Key and Value were marked as readonly, so I could not compile this code).

Is this possible, or do I need to do this in multiple steps?

Thanks.



Select a Dictionary&lt;T1, T2&gt; with LINQ

Does anyone have any idea what the practical differences are between the System.Collections.Specialized.StringDictionary object and System.Collections.Generic.Dictionary&lt;string, string&gt;?

I&#39;ve used them both in the past without much thought as to which would perform better, work better with Linq, or provide any other benefits.


Any thoughts or suggestions as to why I should use one over the other?

StringDictionary vs Dictionary&lt;string, string&gt;

If I want to use objects as the keys for a `Dictionary`, what methods will I need to override to make them compare in a specific way?

Say I have a a class which has properties:

    class Foo {
        public string Name { get; set; }
        public int FooID { get; set; }

        // elided
    } 

And I want to create a:

    Dictionary&lt;Foo, List&lt;Stuff&gt;&gt;

I want `Foo` objects with the same `FooID` to be considered the same group.  Which methods will I need to override in the `Foo` class?

To summarize: I want to categorize `Stuff` objects into lists, grouped by `Foo` objects. `Stuff` objects will have a `FooID` to link them to their category.

Using the field of an object as a generic Dictionary key

I have a class that contains the following two properties:

    public int Id      { get; private set; }
    public T[] Values  { get; private set; }

I have made it `IEquatable&lt;T&gt;` and overriden the `object.Equals` like this:

    public override bool Equals(object obj)
    {
        return Equals(obj as SimpleTableRow&lt;T&gt;);
    }
    
    public bool Equals(SimpleTableRow&lt;T&gt; other)
    {
        // Check for null
        if(ReferenceEquals(other, null))
            return false;

        // Check for same reference
        if(ReferenceEquals(this, other))
            return true;

        // Check for same Id and same Values
        return Id == other.Id &amp;&amp; Values.SequenceEqual(other.Values);
    }

When having override `object.Equals` I must also override `GetHashCode` of course. But what code should I implement? How do I create a hashcode out of a generic array? And how do I combine it with the `Id` integer?

    public override int GetHashCode()
    {
        return // What?
    }

GetHashCode override of object containing generic array

I am beginning to use LINQ in general (so far toXML and toSQL). I&#39;ve seen that sometimes there are two or more ways to achieve the same results. Take this simple example, as far as I understand both return exactly the same thing:

    SomeDataContext dc = new SomeDataContext();
    
    var queue = from q in dc.SomeTable
            where q.SomeDate &lt;= DateTime.Now &amp;&amp; q.Locked != true
            orderby (q.Priority, q.TimeCreated)
            select q;
    
    var queue2 = dc.SomeTable
            .Where( q =&gt; q.SomeDate &lt;= DateTime.Now &amp;&amp; q.Locked != true )
            .OrderBy(q =&gt; q.Priority)
            .ThenBy(q =&gt; q.TimeCreated);

The idea is that there are two ways to express the same thing; I understand that the first method has some limitations and that the &quot;dot notation&quot; is more complete, but besides that, are there any other advantages?

LINQ: Dot Notation vs Query Expression

I&#39;d like to do two things on my progress bar.

 1. Change the green colour to red.
 1. Remove the blocks and make it in one color.

Any information about those two things I wonder how to accomplish will be greatfuly appreaciated!

Thanks.

How to change the color of progressbar in C# .NET 3.5?

I have installed Static and dynamic compression for IIS7, as well as setting the two `web.config` values at my application `Virtual Folder` level. As I understand it, I don&#39;t need to enable compression at the server, or site level anymore, and I can manage it on a per folder basis using my web.config file.

I have two settings in my `.config` file that I have set to customize gzip for my app:
  
    &lt;httpCompression dynamicCompressionDisableCpuUsage=&quot;90&quot;
        dynamicCompressionEnableCpuUsage=&quot;0&quot;&gt;
      &lt;scheme name=&quot;gzip&quot; dll=&quot;%Windir%\system32\inetsrv\gzip.dll&quot; /&gt;
      &lt;dynamicTypes&gt;
        &lt;remove mimeType=&quot;*/*&quot;/&gt;
        &lt;add mimeType=&quot;*/*&quot; enabled=&quot;true&quot; /&gt;
      &lt;/dynamicTypes&gt;
    &lt;/httpCompression&gt;
    &lt;urlCompression doDynamicCompression=&quot;true&quot;
        dynamicCompressionBeforeCache=&quot;true&quot; /&gt;

However, when I run the application, I can clearly see that gzip is not used, because my page sizes are the same. I am also using [YSlow][1] for FireFox, which also confirms that my pages are not being gziped.

What am I missing here? In IIS6 it was a simple matter of specifying the file types, and setting the compression level between 0-10. I don&#39;t see the need documented to specify the file types or compression level, since the defaults seem to cover the file types, and I&#39;m not seeing the level anywhere.


  [1]: http://developer.yahoo.com/yslow/

How can I get gzip compression in IIS7 working?

&gt; **Possible Duplicate:**  
&gt; [Why is there not a ForEach extension method on the IEnumerable interface?](https://stackoverflow.com/questions/101265/why-is-there-not-a-foreach-extension-method-on-the-ienumerable-interface)  

&lt;!-- End of automatically inserted text --&gt;

**EDIT**

For reference, here&#39;s the blog post which eric referred to in the comments

[https://ericlippert.com/2009/05/18/foreach-vs-foreach/][1]

**ORIG**

More of a curiosity I suppose but one for the C# Specification Savants...

Why is it that the ForEach() clause doesn&#39;t work (or isn&#39;t available) for use on IQueryable/IEnumerable result sets...

You have to first convert your results ToList() or ToArray()
Presumably theres a technical limitation to the way C# iterates IEnumerables Vs. Lists...
Is it something to do with the Deferred Execution&#39;s of IEnumerables/IQuerable Collections.
e.g.

    var userAgentStrings = uasdc.UserAgentStrings
        .Where&lt;UserAgentString&gt;(p =&gt; p.DeviceID == 0 &amp;&amp; 
                                !p.UserAgentString1.Contains(&quot;msie&quot;));
    //WORKS            
    userAgentStrings.ToList().ForEach(uas =&gt; ProcessUserAgentString(uas));         
    
    //WORKS
    Array.ForEach(userAgentStrings.ToArray(), uas =&gt; ProcessUserAgentString(uas));

    //Doesn&#39;t WORK
    userAgentStrings.ForEach(uas =&gt; ProcessUserAgentString(uas));


  [1]: https://ericlippert.com/2009/05/18/foreach-vs-foreach/

Content Type	Original Author	Original Content on Stackoverflow
Question	Martin	View Question on Stackoverflow
Solution 1 - C#	LukeH	View Answer on Stackoverflow
Solution 2 - C#	Hamit YILDIRIM	View Answer on Stackoverflow
Solution 3 - C#	Maytham Fahmi	View Answer on Stackoverflow
Solution 4 - C#	mybrave	View Answer on Stackoverflow

Generic method with multiple constraints

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

Solution 3 - C#

Solution 4 - C#

How do I make Vim do normal (Bash-like) tab completion for file names?

How can I convert a DOM element to a jQuery element?

Attributions