.net - click on a button in another application from my C# application?

Question

I want to click on a button in another application from my C# application ,
and I don't have the source code for the application that contains the button

let us say as an example ...can I use windows calculator from my application by clicking its buttons Programmatically
I am using c# and .NET
I think I must use windows api to do this
does anybody have any idea????

Answer 1

Yes, it's not too complicated. You can use FindWindowEx to get the window handle, then iterate through the windows elements and use sendmessage or postmessage to send the WM_Click message.

Here's a codeproject project that does exactly what you want.

Code project