how to install SQL Server Express edition using c# silently

private void button1_Click(object sender, EventArgs e)
        {
            Process p = new Process();
            ProcessStartInfo psi = new ProcessStartInfo();
            psi.FileName = Application.StartupPath.Trim() + @"\SqlServer2005 Express\SQLEXPR.EXE";
            //-q[n|b|r|f]   Sets user interface (UI) level:
            //n = no UI
            //b = basic UI (progress only, no prompts)
            //r = reduced UI (dialog at the end of installation)
            //f = full UI
            psi.Arguments = "/qb username=\"sa\" companyname=\"Rumtek\" addlocal=ALL  disablenetworkprotocols=\"0\" instancename=\"SQLExpress\" SECURITYMODE=\"SQL\" SAPWD=\"lock\"";
            p.StartInfo = psi;
            p.Start();
        }