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c#drag-and-dropnull

C# How to debug Control.DoDragDrop Method

I'm reading a foreign source code and there occurs sometimes a 

NullException

by Drag'n'Drop operation. The problem is, that all parameters are never null, so I'd like to be able to debug this method somehow.

Any ideas ?

Solution

  • Any exception thrown while a drag+drop is in progress is swallowed by a catch all handler in DoDragDrop. You can see the first-chance exception in the Output window but that's all. To get the debugger to stop use Debug + Exceptions, tick the Thrown checkbox on CLR exceptions.