添加引用:

using System.Runtime.InteropServices; 

 

结束进程代码
   [DllImport("user32.dll", CharSet = CharSet.Auto)]
    public static extern int GetWindowThreadProcessId(IntPtr hwnd, out int id);

    public void KillExcellProcess(string path)
    {
        Excel.ApplicationClass excel = new Excel.ApplicationClass();//.applicationclass();
        excel.Workbooks.Open(path, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
        IntPtr t = new IntPtr(excel.Hwnd); 
        int k = 0;
        GetWindowThreadProcessId(t, out k);
        System.Diagnostics.Process p = System.Diagnostics.Process.GetProcessById(k);
        p.Kill();
    }

------解决方案--------------------
学习...还没用过这个东东。