请问为什么Process的kill方法无法结束进程呢？

private void button2_Click(object sender, EventArgs e)
{
string procn = listBox1.SelectedItem.ToString();//进程为在listBox中选中的进程
Process[] localAll = Process.GetProcesses();
foreach (Process p in localAll)//GetProcessesByName(strProcessesByName))
{
if (p.ProcessName.ToUpper().Contains(procn))
{
try
{
//p.CloseMainWindow();//只能关掉主程序框
//p.Close();
p.Kill();
p.WaitForExit(); // possibly with a timeout
}
catch (Win32Exception e1)
{
MessageBox.Show(e1.Message.ToString()); // process was terminating or can't be terminated - deal with it
}
catch (InvalidOperationException e1)
{
MessageBox.Show(e1.Message.ToString()); // process has already exited - might be able to let this one go
}
}
}
}
初学windows开发 以上是我的代码 还有就是CloseMainWindow();也无法关闭 kill能够关闭qq但关闭不了cmd窗口 CloseMainWindow();能关闭qq的会话窗口 也是关闭不了cmd窗口 请问这是为什么呀 ？