Debugging Winforms app

I have a winforms C# app.

On one screen, i have two grids (infragistics) inside split container. Both grid's scrollbars are synced with each other.

App works fine and there is no issue in functionality. The problem is when I switch window from my app to VS or Excel, and come back to my app, the second grid does not render, and it keeps showing the previous app screen. What's weird is this happens only when both grids are in read only more and not when in edit mode.

Ok, I am not asking for solution to my problem, but looking for suggestion, how to profile or debug what is the reason. There is no code on activate or on focus as such. I need to see what causing delay (sometimes infinite) to render t开发者_开发百科he grid.

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Do you have the Profiler in Visual Studio? If so, fire it up and run through the steps you just outlined. If not, go download the free 14 day trial of Ants profiler

Once you run through the steps it will show whether there is any code in the background that is blocking the UI thread. My guess is that you have some CPU intensive code on the UI thread and it's keeping your grid from updating.