Detect Design Time Mode in WPF

In order to detect whether your application is executing as a result of being in a designer use the GetIsInDesignMode method of DesignerProperties as the following demonstrate.

C#

bool designTime = System.ComponentModel.DesignerProperties.GetIsInDesignMode(
    new DependencyObject());

VB.NET

dim designTime as Boolean = DesignerProperties.GetIsInDesignMode(
    New DependencyObject)