I found [this][1] great article by Stephen Toub, which explains that there is actually a performance penalty when using `new Task(...).Start()`, as the start method needs to use synchronization to make sure the task is only scheduled once.

His advice is to prefer using `Task.Factory.StartNew` for .net 4.0. For .net 4.5 `Task.Run` is [the better option][2].


  [1]: http://blogs.msdn.com/b/pfxteam/archive/2010/06/13/10024153.aspx
  [2]: http://blogs.msdn.com/b/pfxteam/archive/2011/10/24/10229468.aspx

Actually in [the article by Stephen Toub][1] he specifies that Task.Run() is exactly equivalent to using Task.Factory.StartNew() with the default parameters:

    Task.Factory.StartNew(someAction, 
    CancellationToken.None, TaskCreationOptions.DenyChildAttach, TaskScheduler.Default);


  [1]: http://blogs.msdn.com/b/pfxteam/archive/2011/10/24/10229468.aspx

I have a variable that holds a callback, and by default it&#39;s value should be null. But this syntax doesn&#39;t seem to work.

    var callback1 : () -&gt; Unit = null
    var callback2 : ((a) -&gt; c, b) -&gt; Unit = null

My current solution is to make sure that callbacks have default implementations.

    var callback1 : () -&gt; Unit = { }
    var callback2 : ((a) -&gt; c, b) -&gt; Unit = { a, b -&gt; }


This, however, makes it hard to check whether or not the callback was set, and possibly default implementation comes at some cost (is that so?). How to assign a null value to a function type variable in Kotlin?

How to assign a null value to a function type variable in Kotlin?

I have inserted some values in the table `DataTab`. &lt;br&gt;

    SomeId: Integer     =&gt; Autogenerated primary key.
    DataId: Guid
    DataNumber: Integer
    DataType: varchar

The above are the column&#39;s in my tables, I want to find, if the table contains Repeated `DataId` values.
It has been long time I had worked with databases. Now I can figure out simple queries. But I found this some what difficult.

I tried the following query, is this correct?

    SELECT * from (Select * from DataTab) AS X 
    where DataId= X.DataId AND SomeId!=X.SomeId

Find duplicate column value in sqlite

Does anyone know if there is any difference between doing `Task.Factory.StartNew` vs `new Task` followed by calling `Start` on the task. Looking at reflector there doesn&#39;t seem to be much difference. So perhaps the only difference is that `Task.Factory.StartNew`returns a task that is already started. Is this correct?

I know that `Task.Factory.StartNew`and `Task.Run` have different default options and `Task.Run` is the preferred option for .Net 4.5.

Task.Factory.StartNew vs new Task

<p>Does anyone know if there is any difference between doing <code>Task.Factory.StartNew</code> vs <code>new Task</code> followed by calling <code>Start</code> on the task. Looking at reflector there doesn't seem to be much difference. So perhaps the only difference is that <code>Task.Factory.StartNew</code>returns a task that is already started. Is this correct?</p>
<p>I know that <code>Task.Factory.StartNew</code>and <code>Task.Run</code> have different default options and <code>Task.Run</code> is the preferred option for .Net 4.5.</p>


[Xunit has a nice feature](https://stackoverflow.com/questions/9110419/test-parameterization-in-xunit-net-similar-to-nunit): you can create one test with a `Theory` attribute and put data in `InlineData` attributes, and xUnit will generate many tests, and test them all.


I want to have something like this, but the parameters to my method are not &#39;simple data&#39; (like `string`, `int`, `double`), but a list of my class:

    public static void WriteReportsToMemoryStream(
        IEnumerable&lt;MyCustomClass&gt; listReport,
        MemoryStream ms,
        StreamWriter writer) { ... }

Pass complex parameters to [Theory]

How can I configure serialization of my Web API to use `camelCase` (starting from lowercase letter) property names instead of `PascalCase` like it is in C#.

Can I do it globally for the whole project?


Web API serialize properties starting from lowercase letter

I read Jon Skeet&#39;s quiz and I wondered why the second sample of mine won&#39;t work while the first one does. 

Why does this yield `true` : 

    object x = new string(&quot;&quot;.ToArray());
    object y = new string(&quot;&quot;.ToArray());
    Console.WriteLine(x == y); //true


But this one does not: 

    var k=&quot;k&quot;;
    //string.intern(k); // doesn&#39;t help
    object x = new string(k.ToArray());
    object y = new string(k.ToArray());
    Console.WriteLine(x == y); //false

*I&#39;m using  fw 4.5 with vs2010.*

Luckily I also have vs2005 installed , same results : 

![enter image description here][1]


  [1]: http://i.stack.imgur.com/Z0r3l.jpg

Empty string as a special case?

I have two classes:

    public class ClassA
    {
      public int? ID {get; set;}
      public IEnumerable&lt;ClassB&gt; Children {get; set;}
    }
    
    public class ClassB
    {
      public int? ID {get; set;}
      public string Name {get; set;}
    }

I want to use fluent assertions to compare to ClassA instances. However I want to ignore the IDs (because the IDs will have been assigned after the save).

I know I can do this:

    expectedA.ShouldBeEquivalentTo(actualA, options =&gt; options.Excluding(x =&gt; x.PropertyPath == &quot;Children[0].ID&quot;));

Which I can obviously repeat for each ClassB in the collection. However I&#39;m looking for a way to exclude the all the IDs (rather than doing an exclude for each element).

I&#39;ve read [this question][1] however if I remove the [0] indexers the assertions fail.

Is this possible?


  [1]: https://stackoverflow.com/questions/15361521/how-do-i-exclude-a-property-of-all-items-in-ienumerable-when-using-shouldbeequiv

How to use Exclude in FluentAssertions for property in collection?

I&#39;ve read around many questions but I&#39;ve not been able to find the right answer for me.
  

As I try to compile a project in VS2012 I have this result:

The command &quot;..\..\tools\bin\nuget pack Packages\Lib.Html.nuspec -    OutputDirectory ..\..\bin\Zip\Packages -NoPackageAnalysis&quot; exited with code 1.

I looked for the line of code in my .csproj file, where the error should be, and there is:  

    &lt;Exec Command=&quot;$(ProjectDir)..\..\tools\bin\nuget pack $(ProjectDir)Packages\Lib.Html.nuspec -OutputDirectory $(OutputPath)Packages -NoPackageAnalysis&quot; /&gt;  

What am I doing wrong?

[EDIT] 
Launching the Debug of that project and ignoring &quot;building errors&quot;, I have a new alert:

&quot;Visual Studio cannot start debugging because the debug target &#39;[project.exe path]&#39; is missing.
Please build the project and retry, or set OutputPath and AssemblyName properties appropriately to point at the correct location for the target assembly.&quot;

How can I resolve the error: &quot;The command [...] exited with code 1&quot;?

I am using HttpClient for sending out request to one of the web api service that I don&#39;t have access to and I need to trace the actual request stream getting to the server from my client.
Is there a way I can hookup the Fiddler to listen to the requests?

I am using the System.Net.Http.HttpClient class for sending out request.

Update: trying to improve this question now as I could not get what I was looking for.
I am using a .Net Client application to connect to a Web Service hosted on my own IIS over HTTP channel. I have done the fiddler debugging earlier with a Website hosted on my IIS and watching the traffic generated between my browser and the WebSite. But when it comes to watching the traffic generated by a .Net client program talking to the web service using HttpClient class, strangely the fiddler does not seem to be able to tap that traffic and does not show anything. Is .Net HttpClient bypassing the WinInet API to connect to the service which results in the fiddler not able to watch the traffic? 

How can I trace the HttpClient request using fiddler or any other tool?

While reading and exploring the dynamic keyword I found following line on [MSDN] (in *[Using Type dynamic (C# Programming Guide)][1]*):

&gt; The type is a static type, but an object of type dynamic bypasses static type checking. In most cases, it functions like it has type object.

What is the meaning of static in above line and how does it bypass static type checking?

  [1]: http://msdn.microsoft.com/en-IN/library/dd264736.aspx



Why is C# dynamic type static?

The `Main` method is the entry point of a C# console application. Thus, for example, if I have to start some threads or services, I will do it within the `Main` method.

I do not see the `Main` method inside a WPF project, so what is the entry point of a WPF application? If I have to start some threads or services, where should write the code for starting them?

**UPDATE:** [this answer][1] summarizes the available solutions, but what are the pros and cons of each solution?


  [1]: https://stackoverflow.com/a/8777142/364056

What is the entry point of a WPF application?

I want to change name of executable file. Like suppose my project name is &quot;SampleDemo&quot;  It will create executable  file Like &#39;SampleDemo.exe&#39; but I want to rename it to  &#39;Demo.exe&#39;

How to change the output name of an executable built by Visual Studio

I have some async code that I would like to add a `CancellationToken` to. However, there are many implementations where this is not needed so I would like to have a default parameter - perhaps `CancellationToken.None`. However,

```c#
Task&lt;x&gt; DoStuff(...., CancellationToken ct = null)
```

yields

&gt; A value of type &#39;&amp;lt;null&amp;gt;&#39; cannot be used as a default parameter because
&gt; there are no standard conversions to type
&gt; &#39;System.Threading.CancellationToken&#39;

and

```c#
Task&lt;x&gt; DoStuff(...., CancellationToken ct = CancellationToken.None)
```

&gt; Default parameter value for &#39;ct&#39; must be a compile-time constant

Is there any way to have a default value for `CancellationToken`?

Default parameter for CancellationToken

I have done quite some search already. However, still having doubts about the &#39;main&#39; parameter in the package.json of a Node project.

 1. How would filling in this field help? Asking in another way, can I start the module in a different style if this field presents?
 2. Can I have more than one script filled into the main parameter? If yes, would they be started as two threads? If no, how can I start two scripts in a module and having them run in parallel?

I know that the second question is quite weird. It is because I have hosted a Node.js application on OpenShift but the application consists of two main components. One being a REST API and one being a notification delivering service.

I am afraid that the notification delivering process would block the REST API if they were implemented as a single thread. However, they have to connect to the same MongoDB cartridge. Moreover, I would like to save one gear if both the components could be serving in the same gear if possible.

Any suggestions are welcome.

How to use the &#39;main&#39; parameter in package.json?

I have an angular service called `requestNotificationChannel`:

    app.factory(&quot;requestNotificationChannel&quot;, function($rootScope) {
    
        var _DELETE_MESSAGE_ = &quot;_DELETE_MESSAGE_&quot;;
    
        function deleteMessage(id, index) {
            $rootScope.$broadcast(_DELETE_MESSAGE_, { id: id, index: index });
        };
        
        return {
           deleteMessage: deleteMessage
        };
    
    });


I am trying to unit test this service using jasmine:

    &quot;use strict&quot;;
    
    describe(&quot;Request Notification Channel&quot;, function() {
        var requestNotificationChannel, rootScope, scope;
    
        beforeEach(function(_requestNotificationChannel_) {
            module(&quot;messageAppModule&quot;);
    
            inject(function($injector, _requestNotificationChannel_) {
                rootScope = $injector.get(&quot;$rootScope&quot;);
                scope = rootScope.$new();
                requestNotificationChannel = _requestNotificationChannel_;
            })
    
            spyOn(rootScope, &#39;$broadcast&#39;);
        });
    
      
        it(&quot;should broadcast delete message notification&quot;, function(done) {
            
            requestNotificationChannel.deleteMessage(1, 4);
            expect(rootScope.$broadcast).toHaveBeenCalledWith(&quot;_DELETE_MESSAGE_&quot;, { id: 1, index: 4 });
            done();       
        });
    });


I read about the Asynchronous Support in Jasmine, but as I am rather new to unit testing with javascript couldn&#39;t make it work.

I am receiving an error :   

    Async callback was not invoked within timeout specified by jasmine.DEFAULT_TIMEOUT_INTERVAL

and my test is taking too long to execute (about 5s).

Can somebody help me providing working example of my code with some explanation?

jasmine: Async callback was not invoked within timeout specified by jasmine.DEFAULT_TIMEOUT_INTERVAL

I have an `async` method:

    public async Task&lt;string&gt; GenerateCodeAsync()
    {
        string code = await GenerateCodeService.GenerateCodeAsync();
        return code;
    }

I need to call this method from a synchronous method.

How can I do this without having to duplicate the `GenerateCodeAsync` method in order for this to work synchronously?

**Update**

Yet no reasonable solution found.

However, I see that `HttpClient` already implements this *pattern*

    using (HttpClient client = new HttpClient())
    {
    	// async
        HttpResponseMessage responseAsync = await client.GetAsync(url);
    
    	// sync
    	HttpResponseMessage responseSync = client.GetAsync(url).Result;
    }

Calling async method synchronously

I am currently reading [Async Javascript][1] by Trevor Burnham.  This has been a great book so far.

He talks about this snippet and console.log being &#39;async&#39; in the Safari and Chrome console. Unfortunately I can&#39;t replicate this. Here is the code:

    var obj = {}; 
    console.log(obj); 
    obj.foo = &#39;bar&#39;;
    // my outcome: Object{}; &#39;bar&#39;;
    // The book outcome: {foo:bar};
If this was async, I would anticipate the outcome to be the books outcome. console.log() is put in the event queue until all code is executed, then it is ran and it would have the bar property.

It appears though it is running synchronously.

Am I running this code wrong? Is console.log actually async?



  [1]: http://pragprog.com/book/tbajs/async-javascript

Content Type	Original Author	Original Content on Stackoverflow
Question	NeddySpaghetti	View Question on Stackoverflow
Solution 1 - C#	NeddySpaghetti	View Answer on Stackoverflow
Solution 2 - C#	o_c	View Answer on Stackoverflow

Task.Factory.StartNew vs new Task

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

Find duplicate column value in sqlite

How to assign a null value to a function type variable in Kotlin?

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