.NET Mouse Click without move the cursor.

Hello, I made already the small tool which is allow me coordinate a click to X,Y with PostMessage. But basically it works only special area on the screen like Desktop or Chrome. The important thing are, we don't move the cursor. (Don't saving and restoring last cursor position, I think you cannot do it without PostMessage function.) And When enter the X,Y location, it must be trigger the click on the screen anyhow. Get the small tool from attachment, fixed it and send back, I will awarded and make the project completed.