Code
 public void deleteTempExcel()
        {
            try
            {
          
                Kill(MyExcel);
            }
            catch(Exception e) { 
               log.Error("关闭Excel进程异常"+e.Message);
            }

        }

        [DllImport("User32.dll", CharSet = CharSet.Auto)]
        public static extern int GetWindowThreadProcessId(IntPtr hwnd, out int ID);
        public static void Kill(Application excel)
        {
            IntPtr t = new IntPtr(excel.Hwnd);   //得到这个句柄，具体作用是得到这块内存入口 

            int k = 0;
            GetWindowThreadProcessId(t, out k);    //得到本进程唯一标志k
            System.Diagnostics.Process p = System.Diagnostics.Process.GetProcessById(k);    //得到对进程k的引用
            p.Kill();      //关闭进程k
        }