protected void Btn_requestStudentSend_Click(object sender, EventArgs e)
        {
            con.Open();
            SqlCommand cmd = con.CreateCommand();

            cmd.CommandType = CommandType.Text;
            cmd.CommandText = "INSERT INTO [REQUEST_STUDENT] ([WORK_DEPARTMENT], [REQUEST_AMOUNT], [WORK_DESCRIPTION], [STUDY_TERMS], [STUDY_YEARS], [AUTH_CONTROL_ID], [AUTH_CONTROL_FIRSTNAME], [AUTH_CONTROL_LASTNAME], [STATUS], [TIMESTAMP]) VALUES (N'" + Ddl_requestStudentDepartment.Text + "', '" + Ddl_requestStudentAmount.Text + "', N'" + Tb_requestStudentWorkDescription.Text + "', '" + Ddl_requestStudentStudyYear.Text + "', '" + Ddl_requestStudentStudyYears.Text + "', '" + Tb_requestStudentAuthID.Text + "', '" + Tb_requestStudentAuthFirstname.Text + "', '" + Tb_requestStudentAuthLastname.Text + "', 'Open', '" + DateTime.Now + "')";
            cmd.ExecuteNonQuery();

            con.Close();
            Gv_authRequestStd.DataBind();
            ScriptManager.RegisterStartupScript(Page, Page.GetType(), "requestStudentModalCenter", "$('#requestStudentModalCenter').modal('hide');", true);
        }
        protected void Btn_authRequestStdFilter_Click(object sender, EventArgs e)
        {
            Thread.Sleep(1000);
            string WORK_DESCRIPTION = Tb_authRequestStdFilter.Text;
            string Filter           = "";

            //Colum of data table
            if (WORK_DESCRIPTION != "")
            {
                Filter = Filter + "WORK_DESCRIPTION like '%" + WORK_DESCRIPTION + "%' and ";
            }

            //Add filter expression of datasource
            if (Filter.Length > 0)
            {
                string FinalFilter = Filter.Remove(Filter.Length - 4, 3);
                SqlDataSourceREQUEST_STUDENT.FilterExpression = FinalFilter;
            }
            else
            {
                Gv_authRequestStd.DataBind();
            }
        }