protected void requisitionListButton_Click(object sender, EventArgs e)
        {
            PurchaseRequisitionBLL purchaseRequisition = new PurchaseRequisitionBLL();

            try
            {
                if (warehouseDropDownList.SelectedValue == "")
                {
                    msgbox.Visible = true; msgTitleLabel.Text = "Validation!!!"; msgDetailLabel.Text = "Warehouse Name field is required.";
                }
                else if (fromDateTextBox.Text.Trim() == "" || LumexLibraryManager.ParseAppDate(fromDateTextBox.Text.Trim()) == "False")
                {
                    msgbox.Visible = true; msgTitleLabel.Text = "Validation!!!"; msgDetailLabel.Text = "Date From field is required.";
                }
                else if (toDateTextBox.Text.Trim() == "" || LumexLibraryManager.ParseAppDate(toDateTextBox.Text.Trim()) == "False")
                {
                    msgbox.Visible = true; msgTitleLabel.Text = "Validation!!!"; msgDetailLabel.Text = "Date To field is required.";
                }
                else
                {
                    string warehouseId = warehouseDropDownList.SelectedValue.Trim();
                    string fromDate = LumexLibraryManager.ParseAppDate(fromDateTextBox.Text.Trim());
                    string toDate = LumexLibraryManager.ParseAppDate(toDateTextBox.Text.Trim());
                    string status = statusDropDownList.SelectedValue.Trim();

                    DataTable dt = purchaseRequisition.GetPurchaseRequisitionsListByWarehouseDateRangeAndStatus(warehouseId, fromDate, toDate, status);

                    purchaseRequisitionListGridView.DataSource = dt;
                    purchaseRequisitionListGridView.DataBind();

                    if (purchaseRequisitionListGridView.Rows.Count > 0)
                    {
                        purchaseRequisitionListGridView.UseAccessibleHeader = true;
                        purchaseRequisitionListGridView.HeaderRow.TableSection = TableRowSection.TableHeader;
                    }
                    else
                    {
                        msgbox.Visible = true; msgTitleLabel.Text = "Data Not Found!!!"; msgDetailLabel.Text = "";
                    }
                }
            }
            catch (Exception ex)
            {
                msgbox.Visible = true; msgTitleLabel.Text = "Exception!!!"; msgDetailLabel.Text = ex.Message;
            }
            finally
            {
                purchaseRequisition = null;
            }
        }