I know I can open Windows Calculator with the following code :
System.Diagnostics.Process.Start(\"calc\");
But I wanna open it in my C# Win
MS Windows Calculator is not a GUI control, it is a standalone application. If you are looking for a .NET calculator control, there are some commercial controls from third party vendors, for example
here
http://download.cnet.com/Softgroup-Net-Calculator-Control/3000-10250_4-10909672.html
or here
http://www.softpedia.com/get/Programming/Components-Libraries/Net-Calculator-Control.shtml