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Error when creating window handle in Winforms MDI App

I have written a Windows Forms MDI Application. In this application the user is allowed to create new windows without any restriction. At some point, after creating several hundreds of windows, the following error occurs:

System.ComponentModel.Win32Exception: Fehler beim Erstellen des Fensterhandles.
   bei System.Windows.Forms.NativeWindow.CreateHandle(CreateParams cp)
   bei System.Windows.Forms.Control.CreateHandle()
   bei System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
   bei System.Windows.Forms.Control.CreateControl()
   bei System.Windows.Forms.Control.ControlCollection.Add(Control value)

How can I test, if the next window to create can be created successfully or not?
Or how can I test, if the program has reached 90% of the maximum handles, so that I can stop creating new windows early enough to ensure, the rest of the programm will go on working correctly, because if I will stop one window before the maximum the program possibly will need more handles without creating new windows and the error will occur later without creating any new window.
So the best would be to test, if the program has reached x% of the maximum handles. Does someone know how to do this or does someone has any other suggestion to solve my problem?
 
Thanks for any help.
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thbruns
Asked:
thbruns
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1 Solution
 
thbrunsAuthor Commented:
Perhaps I should add some information here:

A fix mamimum number of windows, the user can create, is no solution, because the application has different types of windows. Some of them have many child controls others only have a few.
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thbrunsAuthor Commented:
... and I assume the number of available handles differ for some operating systems.

So I need to know how many window handles does my application use at the moment and how many window handles can my application use at maximum.
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thbrunsAuthor Commented:
I have found the solution to get the number of user objects and gdi object per process. See:
http://www.syncfusion.com/FAQ/WindowsForms/FAQ_c73c.aspx
(see section 40.8 on that page)

To get the current used handles use the following code:
System.Diagnostics.Process.GetCurrentProcess().Handle
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