private void cb_ci_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (sw == true)
            {
                if (this.cb_ci.SelectedIndex >= 0)
                {
                    ServiceReference6.WebService2SoapClient ws = new ServiceReference6.WebService2SoapClient();
                    c                    = ws.consultar_ci(cb_ci.SelectedValue.ToString());
                    txtci.Text           = c.Tables[0].Rows[0]["ci"].ToString();
                    txtcarrera.Text      = c.Tables[0].Rows[0]["carrera"].ToString();
                    txtcel.Text          = c.Tables[0].Rows[0]["telefono"].ToString();
                    txtcorreo.Text       = c.Tables[0].Rows[0]["correo"].ToString();
                    txtdireccion.Text    = c.Tables[0].Rows[0]["direccion"].ToString();
                    txtfnac.Text         = c.Tables[0].Rows[0]["fecha_nac"].ToString();
                    txtgenero.Text       = c.Tables[0].Rows[0]["genero"].ToString();
                    txtmaterno.Text      = c.Tables[0].Rows[0]["materno"].ToString();
                    txtnacionalidad.Text = c.Tables[0].Rows[0]["nacionalidad"].ToString();
                    txtnombre.Text       = c.Tables[0].Rows[0]["nombre"].ToString();
                    txtpaterno.Text      = c.Tables[0].Rows[0]["paterno"].ToString();
                    txt_reguniv.Text     = c.Tables[0].Rows[0]["registro"].ToString();

                    ServiceReference6.WebService2SoapClient ws1 = new ServiceReference6.WebService2SoapClient();
                    c = ws1.consultar_materias(txtci.Text.ToString());

                    dgvmateria.DataSource = c;
                    dgvmateria.DataMember = "materias";
                }
            }
        }
        private void Form_con_Load(object sender, EventArgs e)
        {
            ServiceReference6.WebService2SoapClient ws = new ServiceReference6.WebService2SoapClient();
            c = ws.cargar_ci();

            cb_ci.DataSource    = c.Tables[0];
            cb_ci.DisplayMember = "ci";
            cb_ci.ValueMember   = "ci";
            cb_ci.SelectedIndex = -1;
            sw = true;
        }