I ran dotTrace on my application (which is having some issues).

IntPtr System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr, IntPtr, Int32, IntPtr, IntPtr)

Void System.Windows.Forms.UnsafeNativeMethods.WaitMessage()

Are the two main functions that came up, taking about 94% of the application time.

Since I didn't know what these two functions were, I ran through my code line by line. It runs smooth and efficiently until a point where it just hangs. "newFrm.Show()".

The newFrm only contains a textbox. The larger the file I load into the text box (it's a notepad program), the longer it takes. Now normally this makes sense, but it takes about 30 seconds for a 167 kB file.

Now I'm not sure what to do. It runs incredibly slow/stops functioning when you load a textfile and try to resize the window containing the text file too.

Then I realized that it is only struggling to open text files with a long string of hex inside (ie) "XX-XX-XX-" etc. With other similarly sized files it struggles with resizing somewhat, but opens within a couple seconds.

Does this have something to do with the textbox properties? I've set it to multiline and set maximum characters to 0 (so unlimited).

How do I solve this issue? Is there some way I can see what is being called in those functions?