c#中运行外部应用程序的方法

using System.Diagnostics

.
.
.
private void buttonItem3_Click(object sender, System.EventArgs e)
  {
   Process mPro=new Process();
   string path=System.Environment.GetFolderPath(Environment.SpecialFolder.System);
   mPro.StartInfo.FileName=path+"\\calc.exe";
   mPro.Start();
  }