Editing XAML leads Visual Studio's Designer to crash

Question

Original Question

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I\'m working on a WPF application with Visual Studio 2010, using Telerik.

I have been dealing with a lot of crashes ev

Answer 1

I believe the problem you are seeing is related to one of the controls you are using.

Let me first show you a way of reproducing this problem; if it is the same issue you are seeing. (I'm using VS 2013 which handles this issue a little better than vs 2010)

Firstly, I created a custom control which is a TextBox; and I have code that looks something like this.

public class CustomTextBox : TextBox
{
    public string testText { get; set; }

    public CustomTextBox()
        : base()
    {
        if (string.IsNullOrEmpty(testText))
        {
            throw new ArgumentNullException();
        }
    }
}

then I put this control into the xaml

All I'm doing is throwing an exception when a property is null when the control calls its constructor (which it will do when in the designer as the designer attempts to new it up and render it).

In VS2013 I simply have a red line underneath the control in the XAML itself, but from past experience with VS2010 this issue did cause the designer to fall over.

What I may suggest you do, is go through the XAML without the designer and take out any 3rd party/custom control's one at a time. One of these controls may be throwing an exception which can produce what you are seeing. If its one of the Telerik controls, contacting them is a option.