C#调用外部dos命令并取得返回結果

private static string CmdPing(string strIp)
         {

             Process p = new Process();
            //设定程序名
             p.StartInfo.FileName = "cmd.exe";
            //关闭Shell的使用
             p.StartInfo.UseShellExecute = false;
            //重定向标准输入
             p.StartInfo.RedirectStandardInput = true;
            //重定向标准输出
             p.StartInfo.RedirectStandardOutput = true;
            //重定向错误输出
             p.StartInfo.RedirectStandardError = true;
            //设置不显示窗口
             p.StartInfo.CreateNoWindow = true;

            string pingrst;
            //启动进程
             p.Start();
            //输入要执行的命令，这里就是ping
             p.StandardInput.WriteLine("ping -n 1 " + strIp);
             p.StandardInput.WriteLine("exit");
            //从输出流获取命令执行结果
            string strRst = p.StandardOutput.ReadToEnd();

            //分析strRst字符串就可以知道网络的连接情况
            if (strRst.IndexOf("(0% loss)") != -1)
                 pingrst = "连接";
            else if (strRst.IndexOf("Destination host unreachable.") != -1)
                 pingrst = "无法到达目的主机";
            else if (strRst.IndexOf("Request timed out.") != -1)
                 pingrst = "超时";
            else if (strRst.IndexOf("Unknown host") != -1)
                 pingrst = "无法解析主机";
            else
                 pingrst = strRst;

             p.Close();

            return pingrst;

         }