title: how to programmatically click on a button in running app using C# code
body: <p>I want to write a C# program which will launch an .exe (this is an easy job, I know how to do it.) but now I want to add some more functionality to it. 
     I want to take user inputs to my program and want to pass them to running .exe as a input.Also I want to click on a particular button available on the exe window. Important thing is, I want to do it programatically without user knowledge that we are actually running that exe in background. 
     Please let me know if it is possible. It is very urgent. </p>