Scraping text from outside application's non-standard window

[nightmares]

Hey Everyone

I'm writing an application, and part of it includes scraping the text from a chat box in another application currently running on the computer. So, if the chat box in another running program contains something like
Me: Hi
You: Hi
Me: lol
I want to get "Me: Hi You: Hi Me: lol" into a string variable in my application so that I can parse it as needed. I have tried using some win32 api calls as follows:

			IntPtr handle = new IntPtr(11111); //note: i can get the window handle, this isn't the issue
			int nChars = GetWindowTextLength(handle); //win32 function
			StringBuilder Buff = new StringBuilder(nChars);

			if (GetWindowText(handle, Buff, nChars) > 0)  //also win32 function
			{
				Console.WriteLine(Buff.ToString());
				Console.WriteLine(handle.ToString());
			}
			else
			{
				Console.WriteLine("fail");
			}

I also tried:

			IntPtr window_hwnd = 313312; //I can find the window handle, this isn't the problem
			Int32 txtlen;

			txtlen = SendMessage(window_hwnd, WM_GETTEXTLENGTH, IntPtr.Zero, IntPtr.Zero);

			if (txtlen == 0)

				return "";



			txtlen = txtlen + 1;

			StringBuilder txt = new StringBuilder(txtlen);

			SendMessage(window_hwnd, WM_GETTEXT, txtlen, txt);

			Console.WriteLine(txt.ToString());

Note that above these code fragments are all of the dllimports for the windows functions. Also, the code fragments work for other windows programs, like notepad. From what I understand, GetWindowText and sending a WM_GETTEXT message only work if the target window is a standard windows control. Because they aren't returning anything when I know there is text in the chat window, I have concluded that the chat window is not a standard windows control. Does anyone know how to get the text out of a non-standard windows control? Note: I'm trying to use the windows api but if I can't, that's ok.

Thanks for any comments/suggestions