.net - NullReferenceException with ToolTip.CreateHandle -


When we try to update a tool tip, we can easily get errors

< Pre> ToolTip .etToolTip (myLabel, customDataStructure)

The error we get is a NullReferenceException: Object reference is not set to an object instance

Does anyone know the reason for this?

Is a simple try / hold which is NullReferenceException a viable option? We do not want that we blow our entire application.

I think that you are calling 'codeTool.TipToolTip' from an event handler and that handler Sometimes a fire occurs before creating a label. You should probably protect it with an inquiry for label null , and then make sure that the tip of the device is started on the label's load event.

You definitely should not catch this exception because this hides the problem.


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