asp.net获取指定IP的Mac地址

/**//// <summary>
/// 读取IP地址对应的MAC地址
/// </summary>
/// <param name="ip">访问者的IP</param>
/// <returns></returns>
public string getmac(string ip)
...{
    string result="";
    try
    ...{
        string dirresults="";
        System.Diagnostics.ProcessStartInfo psi=new System.Diagnostics.ProcessStartInfo();
        System.Diagnostics.Process proc = new System.Diagnostics.Process();
        psi.FileName = "nbtstat";
        psi.RedirectStandardInput=false;
        psi.RedirectStandardOutput=true;
        psi.Arguments="-A "+ip;
        psi.UseShellExecute=false;
        proc=System.Diagnostics.Process.Start(psi);
        int x=-1;
        while(x<=-1)
        ...{
            if(dirresults!=null)
            ...{
                x=dirresults.Trim().ToLower().IndexOf("mac address");
                if (x>-1)
                ...{
                    break;
                }
            }
            dirresults=proc.StandardOutput.ReadLine().ToString();
        };
        proc.WaitForExit();
        result=ValueSepR(dirresults.Trim(),"=");
        return result;
    }
    catch
    ...{
        return "";
    }
}