I am working on a little side project that needs to read information from a text box of another program. I have used FindWindow, FindWindowEx, GetWindowText and was able to grab the initial values of the text box. The problem is that this is an ever changing value that I want to monitor in real time. Let me give you an example of what is happening and what needs to happen.

Output.exe is putting a random number into TextBox1 with an initial value of 1.5. I programmed GetText.exe to grab the text from TextBox1 and it does this successfully every time I run through the routine, but it will always return the inital value of 1.5 it wont change with Output.exe.

From what I have found thus far I think I am going to have to establish a System hook to monitor the text box in real time. My question is pretty much what API's should I be looking at, what types of web resources are there for this type of application, and is this NT/2000/XP/Vista specific or will I be able to port to a 9x machine?

Any and all help is appreciated.