Question

I have a big winform class that calls from a little one like this:

    void login()
    {           
        mainForm f1 = new mainForm();                
        f1.ShowDialog();
    }

The mainForm will take lots of memory after login (I check it in Task Manager). After closing the mainForm, program returns to login form. At this step I check Task Manager again and see that my program has not released the memory that mainForm used. And after some login, my program crashes and shows “Out of Memory” error.

I have to say that I tested f1.Dispose(), f1=null, GC.Collect() and every other methods that I found.

It will only releases the memory when I close the login form (Its the starting class used in Application.Run)

I want to destroy the mainForm instance (f1) and all resources of this form just like when I close the program.

Answer 1

Couple of thoughts:

• wrap your code in a using statement
• static event handlers / variables usually cause these sort of these problems
• are you using any third party controls? check their forums they may have known memory leak problems
• are you using any frameworks for UI composition eg PRISM
• have you tried windbg or sos? http://blogs.msdn.com/b/delay/archive/2009/03/11/where-s-your-leak-at-using-windbg-sos-and-gcroot-to-diagnose-a-net-memory-leak.aspx