public partial class CommandLine : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        System.Diagnostics.Process si = new System.Diagnostics.Process();
        si.StartInfo.WorkingDirectory = "c:\\";
        si.StartInfo.UseShellExecute = false;
        si.StartInfo.FileName = "cmd.exe";
        si.StartInfo.Arguments = "dir";
        si.StartInfo.CreateNoWindow = true;
        si.StartInfo.RedirectStandardInput = true;
        si.StartInfo.RedirectStandardOutput = true;
        si.StartInfo.RedirectStandardError = true;
        si.Start();
        string output = si.StandardOutput.ReadToEnd();
        si.Close();
        Response.Write(output);
    }
}