ImageURL and GetWebResourceURL

I have this at the top of my file: 

[assembly: WebResource("WebLayer.Resources.Warning.png", "image/png")]


and I'm doing this in my Page_Load(..) routine:

Warning_Image.ImageUrl = Page.ClientScript.GetWebResourceUrl(this.GetType(), "WebLayer.Resources.Warning.png");

The file is located under my project named "WebLayer" in a directory called "Resources".  The file is named "Warning.png" and is marked as an Embedded Resource.  This doesn't work for me (I get the red x) and I cannot figure out what I'm doing wrong.  Please help, I feel like an idiot (smacks forehead).

David
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