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Controls Disappear in Custom Control Design View

Posted By:      Posted Date: September 08, 2010    Points: 0   Category :ASP.Net
I have a site using eight (so far) custom web user controls  and two of them have started misbehaving in design view.  When designing the control itself some (in one control) or all (in the other) regular controls (labels, text boxes, etc.) disappear from the design view surface.  They can still be seen in the source view and if the control is hosted on a regular .aspx page the control displays properly.  The code window recognizes all controls in the objects dropdown list and I can write appropriate code.  The controls run properly on their hosted pages.  If I switch to Split view and select controls in the source view panel a very small area od the design surface becomes selected (like one pixel for any of us who remember programming old DOS applications with 80-column screens) but no controls can be seen. In short, the controls work in every respect except that I cannot see all or part of the design surface in Design view when editing the controls directly.  I've double-tripple checked the source code for anything that may be causing this and just don't see anything.  (The controls aren't that complicated.)

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