protected void txtTransferVendor_TextChanged(object sender, EventArgs e) { if (txtTransferVendor.Text != "") { DataTable dtvendor = locationMaster.GetVendorID(txtTransferVendor.Text.Trim()); if (dtvendor != null && dtvendor.Rows.Count > 0) { hidTransferVendor.Value = dtvendor.Rows[0]["pVendMstrID"].ToString().Trim(); } else { txtTransferVendor.Text = ""; ScriptManager.RegisterClientScriptBlock(txtTransferVendor, typeof(TextBox), "Valid", "alert('Invalid vendor #');", true); } } else { hidTransferVendor.Value = ""; } }