private void DataLoad()
        {
            string strQuery = "";
            if (txtManagementId.Text.Trim() != "")
            {
                if (strQuery != "")
                {
                    strQuery = strQuery + " AND ";
                }
                strQuery = strQuery + " UserId LIKE '%" + txtManagementId.Text.Trim() + "%' ";
            }

            if (txtUserId.Text.Trim() != "")
            {
                if (strQuery != "")
                {
                    strQuery = strQuery + " AND ";
                }
                strQuery = strQuery + " UserNumber LIKE '%" + txtUserId.Text.Trim() + "%' ";
            }

            if (cboUserGrade.SelectedValue != "")
            {
                if (strQuery != "")
                {
                    strQuery = strQuery + " AND ";
                }
                strQuery = strQuery + " UserGrade = '" + cboUserGrade.SelectedValue + "' ";
            }
}