How Do I Detect Design-Time Vs Run-Time in a .NET Control?

When you're designing custom controls in Visual Studio .NET, you'll often need to distinguish between design-time and run-time. You could, for example, load a static image, or create a made-up DataSource at design-time while you use a real image or DataSource at run-time. The following snippet allows you to determine whether you're currently in design-time or not.
if (this.Site != null && this.Site.DesignMode == true)
  // Design Mode
  // Run-time

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On Monday, June 26, 2006 8:20:00 PM Kris Krause said:
Thanks for the tip.

Works the same way with WinForm controls .DesignMode
On Sunday, February 10, 2008 7:15:30 PM Eric Sierp said:
Good suggestion.  What about detecting Design Time in the constructor of a control though?  I have a control for Windows Mobile that needs to access System Properties such as PowerBatteryStrength upon creation so that it can subscribe to the change events.  Site, and therfore DesignMode, is not available in the constructor of a control.  Does anyone have any suggestions for how to do this?

On Sunday, February 10, 2008 9:39:54 PM Imar Spaanjaars said:
Hi Eric,

Sorry, no suggestions. It's been a while since I did anything "mobile"...

On Tuesday, November 25, 2008 3:38:18 PM Michael Finlan said:
Hi Imar,

I appreciate this article. It has been a long time I could never find a way to do this and believe me I looked.



On Saturday, January 10, 2009 11:20:43 PM Eugen said:
I have a post about this problem (including detecting the design mode in a usercontrol constructor). Please read this article, maybe you will find it useful:

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