protected void ddlPOList_SelectedIndexChanged(object sender, Telerik.Web.UI.RadComboBoxSelectedIndexChangedEventArgs e)
    {
        decimal batch_no = WebTools.DMaxchar("BATCH_NO", "PIP_PO_BATCH_PLAN", " WHERE PO_ID='" + ddlPOList.SelectedValue + "'");

        txtBatchNo.Text    = (batch_no + 1).ToString();
        txtRevBatchNo.Text = (batch_no + 1).ToString();
        txtRevNo.Text      = "1";
    }