Try to get the page from the handler and use [`ResolveUrl`][1], or create a Control object...

    (HttpContext.Current.Handler as Page).ResolveUrl(&quot;~/virtualpath&quot;);

Or use [`VirtualPathUtility.ToAppRelative(string)`][2] or [`VirtualPathUtility.ToAbsolute(string)`][3]


For example:

    System.Web.VirtualPathUtility.ToAbsolute(&quot;~/Styles/Contoso.xslt&quot;);

returns

    /WebSite/Styles/Contoso.xslt

  [1]: http://msdn.microsoft.com/en-us/library/system.web.ui.control.resolveurl.aspx
  [2]: http://msdn.microsoft.com/en-us/library/ms150163.aspx
  [3]: http://msdn.microsoft.com/en-us/library/ms150160.aspx

This question on SO ([ASP.Net: Using System.Web.UI.Control.ResolveUrl() in a shared/static function][1]) looks kind of helpful...Basically, you can use the [VirtualPathUtility][2] class which is under the System.Web namespace. There is an additional answer to that question which says to be careful of QueryString parameters, but a solution to that is also provided.

At the same time, Rick Strahl&#39;s code is pretty neat!

  [1]: https://stackoverflow.com/questions/26796/asp-net-using-system-web-ui-control-resolveurl-in-a-shared-static-function
  [2]: http://msdn.microsoft.com/en-us/library/system.web.virtualpathutility.aspx

Use something like this - 
Controls is a folder name in your application and myController is the controller name. to create and instance and load the controller you can do it by: 

    Controls_myController ctrl = Page.LoadControl(Page.ResolveUrl(&quot;controls/myController.ascx&quot;));

Hope this helps.

I’m doing some refactoring of a simple application to follow MVVM and my question is how do I move a SelectionChanged event out of my code behind to the viewModel? I’ve looked at some examples of binding elements to commands but didn’t quite grasp it. Can anyone assist with this. Thanks!

**Can anyone provide a solution using the code below? Many thanks!** 


    public partial class MyAppView : Window 
	{
		public MyAppView()
		{
			InitializeComponent();

            this.DataContext = new MyAppViewModel ();

			// Insert code required on object creation below this point.
		}

        private void contactsList_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
        {
            //TODO: Add event handler implementation here.           
            //for each selected contact get the labels and put in collection 

            ObservableCollection&lt;AggregatedLabelModel&gt; contactListLabels = new ObservableCollection&lt;AggregatedLabelModel&gt;();

            foreach (ContactListModel contactList in contactsList.SelectedItems)
            {
                foreach (AggregatedLabelModel aggLabel in contactList.AggLabels)
                {
                    contactListLabels.Add(aggLabel);
                }
            }
            //aggregate the contactListLabels by name
            ListCollectionView selectedLabelsView = new ListCollectionView(contactListLabels);

            selectedLabelsView.GroupDescriptions.Add(new PropertyGroupDescription(&quot;Name&quot;));
            tagsList.ItemsSource = selectedLabelsView.Groups;
        }
	}

WPF Binding UI events to commands in ViewModel

Can someone explain the difference between `MultiAutoCompleteTextView` and  `AutoCompleteTextView`?

Difference between MultiAutoCompleteTextView and AutoCompleteTextView

I am looking for a way to resolve a relative url the way you would with a page or control instance ([MSDN Docs][1]) such as:

    Page.ResolveUrl(&quot;~/common/Error.aspx&quot;);



...but when I only have an HttpContext available to me, such as when I am in a HttpHandler. 

Will I need to use a custom function, such as the one seen [here][2]?

Or is there a way to get at the underlying function used by the Page.


  [1]: http://msdn.microsoft.com/en-us/library/system.web.ui.control.resolveurl(v=vs.71).aspx
  [2]: http://www.west-wind.com/weblog/posts/154812.aspx

ResolveUrl without an ASP.NET Page

I am looking for a way to resolve a relative url the way you would with a page or control instance (<a href="http://msdn.microsoft.com/en-us/library/system.web.ui.control.resolveurl(v=vs.71).aspx" target="_blank" rel="noopener noreferrer">MSDN Docs</a>) such as:
<pre><code class="hljs language-arduino">Page.ResolveUrl("~/common/Error.aspx");
</code></pre>
...but when I only have an HttpContext available to me, such as when I am in a HttpHandler.
Will I need to use a custom function, such as the one seen <a href="http://www.west-wind.com/weblog/posts/154812.aspx" target="_blank" rel="noopener noreferrer">here</a>?
Or is there a way to get at the underlying function used by the Page.

I&#39;m working with the Code First feature of Entity Framework and I&#39;m trying to figure out how I can specify the column data types that should be created when the database is auto-generated.

I have a simple model:

    public class Article
    {
        public int ArticleID { get; set; }

        public string Title { get; set; }
        public string Author { get; set; }
        public string Summary { get; set; }
        public string SummaryHtml { get; set; }
        public string Body { get; set; }
        public string BodyHtml { get; set; }
        public string Slug { get; set; }

        public DateTime Published { get; set; }
        public DateTime Updated { get; set; }

        public virtual ICollection&lt;Comment&gt; Comments { get; set; }
    }

When I run my application, a SQL CE 4.0 database is automatically created with the following schema:

![DB Schema][1]

So far, so good! However, the data I will be inserting into the `Body` and `BodyHtml` properties is routinely larger than the maximum allowed length for the `NVarChar` column type, so I want EF to generate `Text` columns for these properties.

However, I cannot seem to find a way to do this! After quite a bit of Googling and reading, I tried to specify the column type using `DataAnnotations`, from information found in [this answer][2]:

    using System.ComponentModel.DataAnnotations;

    ...

    [Column(TypeName = &quot;Text&quot;)]
    public string Body { get; set; }

This throws the following exception (when the database is deleted and the app is re-run):

    Schema specified is not valid. Errors: (12,6) : error 0040: The Type text is not qualified with a namespace or alias. Only PrimitiveTypes can be used without qualification.

But I have no idea what namespace or alias I should be specifying, and I couldn&#39;t find anything that would tell me.

I also tried changing the annotation as per [this reference][3]:

    using System.Data.Linq.Mapping;

    ...

    [Column(DbType = &quot;Text&quot;)]
    public string Body { get; set; }

In this case a database _is_ created, but the `Body` column is still an `NVarChar(4000)`, so it seems that annotation is ignored.

Can anyone help? This seems like it should be a fairly common requirement, yet my searching has been fruitless!


  [1]: http://i.stack.imgur.com/A4OI9.gif
  [2]: https://stackoverflow.com/questions/4829776/generate-money-type-fields-using-code-first-ef-ctp5/4833477#4833477
  [3]: http://msdn.microsoft.com/en-us/library/system.data.linq.mapping.columnattribute.dbtype.aspx

How do I specify that a property should generate a TEXT column rather than an nvarchar(4000)

I want to create a shortcut pointing to some EXE file, on the desktop, using .NET Framework 3.5 and relying on an official Windows API. How can I do that? 


Create a shortcut on Desktop

For example:


    public class Person
    {
        public Person()
        {
        }
    
        ~Person()
        {
        }
    }


When should I manually create a destructor?
When have you needed to create a destructor? 

When should I create a destructor?

As you know, it is not allowed to use the Array-initialisation syntax with Lists. It will give a compile-time error. Example:

    List&lt;int&gt; test = { 1, 2, 3} 
    // At compilation the following error is shown:
    // Can only use array initializer expressions to assign to array types. 


However today I did the following (very simplified):

    class Test
    {
         public List&lt;int&gt; Field;
    }

    List&lt;Test&gt; list = new List&lt;Test&gt;
    {
        new Test { Field = { 1, 2, 3 } }
    };

The code above compiles just fine, but when run it will give a &quot;Object references is not set to an object&quot; run-time error.

I would expect that code to give a compile-time error. My question to you is: Why doesn&#39;t it, and are there any good reasons for when such a scenario would run correctly?

This has been tested using .NET 3.5, both .Net and Mono compilers.

Cheers.

List&lt;int&gt; test = {1, 2, 3} - is it a feature or a bug?

I&#39;m using Linq To XML

    new XElement(&quot;Prefix&quot;, Prefix == null ? &quot;&quot; : Prefix)

but I want to do some computation to the prefix before adding it to the xml, like eliminating spaces, special chars, some calculations etc 

I don&#39;t want to create functions because this ones won&#39;t be of any help on any other part of my program but this, so is there any way to create inline functions??

How to make inline functions in C#

Can anyone point me to a good implementation of a basic Windows Forms TextBox that will initially show watermark text that disappears when the cursor enters it? I think I can create my own with some creative use of Enter and Leave events, but I&#39;m sure there&#39;s a perfectly usable implementation sitting around somewhere. I saw the WPF implementation and if necessary I could nest it, but a native WinForms TextBox derivative would be better.

I have this so far; haven&#39;t tried it yet but does anyone see any glaring problems?

    public class WatermarkTextBox:TextBox
    {
        public string WatermarkText { get; set; }

        public Color WatermarkColor { get; set; }

        private Color TextColor { get; set; }

        private bool isInTransition;

        public WatermarkTextBox()
        {
            WatermarkColor = SystemColors.GrayText;
        }

        private bool HasText { get { return Text.IsNotNullOrBlankOr(WatermarkText); }}

        protected override void OnEnter(EventArgs e)
        {
            base.OnEnter(e);

            if (HasText) return;

            isInTransition = true;
            ForeColor = TextColor;
            Text = String.Empty;
            isInTransition = false;
        }

        protected override void OnForeColorChanged(EventArgs e)
        {
            base.OnForeColorChanged(e);
            if (!isInTransition) //the change came from outside
                TextColor = ForeColor;
        }

        protected override void OnLeave(EventArgs e)
        {
            base.OnLeave(e);

            if (HasText) return;

            isInTransition = true;
            ForeColor = WatermarkColor;
            Text = WatermarkText.EmptyIfNull();
            isInTransition = false;
        }
    }

EDIT: The above would have eventually worked with some finessing, but the CueProvider worked much better. Here&#39;s my final implementation:

    public class WatermarkTextBox:TextBox
    {
        private string watermarkText;
        public string WatermarkText
        {
            get { return watermarkText; }
            set
            {
                watermarkText = value;
                if (watermarkText.IsNullOrBlank())
                    CueProvider.ClearCue(this);
                else
                    CueProvider.SetCue(this, watermarkText);
            }
        }
    }

I could have integrated the CueProvider functionality completely, but this works beautifully.

Watermark TextBox in WinForms

Can private classes exist in C#, other than in Inner classes? 

Concept of Private class in C#

I noticed that with the optional parameters in C# 4 if you specify an  optional parameter on an interface you ***don,t*** have to make that parameter optional on any implementing class:

    public interface MyInterface
    {
    	void TestMethod(bool flag = false);
    }
    
    public class MyClass : MyInterface
    {
    	public void TestMethod(bool flag)
    	{
    	    Console.WriteLine(flag);
    	}
    }

and therefore:

    var obj = new MyClass();    	
    obj.TestMethod(); // compiler error

    var obj2 = new MyClass() as MyInterface;
    obj2.TestMethod(); // prints false

Does anyone know why optional parameters are designed to work this way?

On one hand I suppose the ability to override any default values specified on the interfaces is useful though to be honest I&#39;m not sure if you should even be able to specify default values on the interface as that should be an implementation decision.

On the other hand, this disconnect means you can&#39;t always use the concrete class and the interface interchangeably. This of course, wouldn&#39;t be a problem if the default value is specified on the implementation, but then if you&#39;re exposing your concrete class as the interface (using some IOC framework to inject the concrete class for instance) then really there&#39;s no point having the default value as the caller will have to always provide it anyway.

Why are C# 4 optional parameters defined on interface not enforced on implementing class?

&gt; **Possible Duplicate:**  
&gt; [Populating a list of integers in .NET](https://stackoverflow.com/questions/49214/populating-a-list-of-integers-in-net)  

&lt;!-- End of automatically inserted text --&gt;

Is there a simpler or more elegant way of initializing a list of integers in C# other than this?

    List&lt;int&gt; numberList = new List&lt;int&gt;() { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

or

    for(int i = 1; i &lt;= 10; i++)
    {
        numberList.Add(i);
    }

It just doesn&#39;t seem very practical - especially if the list was to contain a large number of values. Would a loop be a more practical solution?

Thanks,

CC


Easier way to populate a list with integers in .NET

I have a DropDownList object in my web page. When I click on it and select a different value, nothing happens, even though I have a function wired up to the `SelectedIndexChanged` event.

First, the actual object&#39;s HTML code:

    &lt;asp:DropDownList ID=&quot;logList&quot; runat=&quot;server&quot; 
	       onselectedindexchanged=&quot;itemSelected&quot;&gt;
    &lt;/asp:DropDownList&gt;

And this is that function, `itemSelected`:

    protected void itemSelected(object sender, EventArgs e)
	{
		Response.Write(&quot;Getting clicked; &quot; + sender.GetType().ToString());
		FileInfo selectedfile;
		Response.Write(&quot;&lt;script&gt;alert(&#39;Hello&#39;)&lt;/script&gt;&quot;);
		foreach (FileInfo file in logs)
		{
			if (file.Name == logList.Items[logList.SelectedIndex].Text)
			{
				Response.Write(&quot;&lt;script&gt;alert(&#39;Hello&#39;)&lt;/script&gt;&quot;);
			}
		}
	}

None of the Responses appear, and that portion of JavaScript is never run. I&#39;ve tried this on the latest 3.6 version of Firefox, as well as Internet Explorer 8. This is being served from a Windows Server 2003 R2 machine, running ASP.NET with the .NET Framework version 4.

DropDownList&#39;s SelectedIndexChanged event not firing

    protected void Page_Load(object sender, EventArgs e)
    {
        XmlDocument doc = new XmlDocument();
        try
        {
            string path = Server.MapPath(&quot;.&quot;);
            doc.Load(path+&quot;whatever.xml&quot;);
        }
        catch (Exception ex)
        {
            lblError.Text = ex.ToString();
            return;
        }
    
        // Convert XML to a JSON string
        string JSON = XmlToJSON(doc);
        
        // Replace \ with \\ because string is being decoded twice
        JSON = JSON.Replace(@&quot;\&quot;, @&quot;\\&quot;);
        
        // Insert code to process JSON at end of page
        ClientScriptManager cs = Page.ClientScript;
        cs.RegisterStartupScript(GetType(), &quot;SpaceJSON&quot;, &quot;space_processJSON(&#39;&quot; + JSON + &quot;&#39;);&quot;, true);
    }

Instead if of loading the xml from a file, how do I load it from a string?

XmlDocument - load from string?

There are plenty of examples for having it worked on an MVC application. How is it done on Web Forms?

How can I implement Ninject or DI on asp.net Web Forms?

what is the best way to compare two objects and find the differences?

    Customer a = new Customer();
    Customer b = new Customer();



Compare two objects and find the differences

I&#39;m currently developing a site using ASP.Net MVC3 with Razor. Inside the &quot;View/Shared&quot; folder, I want to add a subfolder called &quot;Partials&quot; where I can place all of my partial views (for the sake of organizing the site better.

I can do this without a problem as long as I always reference the &quot;Partials&quot; folder when calling the views (using Razor):

    @Html.Partial(&quot;Partials/{ViewName}&quot;)

My question is if there is a way to add the &quot;Partials&quot; folder to the list that .Net goes through when searching for a view, this way I can call my view without having to reference the &quot;Partials&quot; folder, like so:

    @Html.Partial(&quot;{ViewName}&quot;)

Thanks for the help!


Content Type	Original Author	Original Content on Stackoverflow
Question	cweston	View Question on Stackoverflow
Solution 1 - C#	BrunoLM	View Answer on Stackoverflow
Solution 2 - C#	davidsleeps	View Answer on Stackoverflow
Solution 3 - C#	Mani	View Answer on Stackoverflow

ResolveUrl without an ASP.NET Page

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

Solution 3 - C#

Difference between MultiAutoCompleteTextView and AutoCompleteTextView

WPF Binding UI events to commands in ViewModel

Attributions