//called to refresh all the fields and datagridview
private void populateFields(Button disableButton, Button enableButton, int index)
{
orders = OrderDB.GetOrders();
txtOrderID.Text = orders[index].OrderID.ToString();
txtCustomerID.Text = orders[index].CustomerID;
dtpOrderDate.Value = (DateTime)orders[index].OrderDate;
dtpRequiredDate.Value = (DateTime)orders[index].RequiredDate;
if (orders[index].ShippedDate != null) // if the shippeddate is not null
{
dtpShippedDate.Format = DateTimePickerFormat.Long;
dtpShippedDate.Value = (DateTime)orders[index].ShippedDate;
isNull = false;
}
else //shipped date is null
{
dtpShippedDate.CustomFormat = " ";
dtpShippedDate.Format = DateTimePickerFormat.Custom;
isNull = true;
}
List <OrderDetails> orderDetails_List = OrderDetailsDB.GetOrdersDetails(orders[index].OrderID);
dgvOrderDetails.DataSource = orderDetails_List;
txtTotalCharges.Text = CalculateCharges(orderDetails_List).ToString("c");
Disablebuttion(disableButton, enableButton, index);
}
// need to retrieve the list of OrderIDs upon form loading
private void Form1_Load(object sender, EventArgs e)
{
try
{
orders = OrderDB.GetOrders(); // get the list of OrderIDs
foreach (var order in orders) // add items to the OrderID combobox
{
orderIDComboBox.Items.Add(order.OrderID);
}
}
catch (Exception ex)
{
MessageBox.Show("Error while loading order data: " + ex.Message,
ex.GetType().ToString());
}
}
// ----------------- Methods ------------------
// Do Updates Against Database
private void TryUpdate()
{
// 1. pass listToUpdate to OrderDB update method
// 2.1 if thrown, show exception message
// 2.2 if no exception, return a List<int> (collection of update failed OrderIDs)
// 3. show user how many updates succeed, how many failed, and OrderID of failed ones
// 4.1 if all updates succeed, clear listToUpdate, disable save btn (only enabled when there are unupdated changes)
// 4.2 if there are failed updates, add failed orders to listToUpdate again, reload orders table
var failedOrderIDs = new List <int>();
try
{
// try to update changes
failedOrderIDs = OrderDB.UpdateOrders(listToUpdate);
// create error message shows which orders failed update
string failMsg = "Order ID: ";
foreach (var failedID in failedOrderIDs)
{
failMsg += failedID + ", ";
}
failMsg += "did not update due to concurrency issue, please try again later.";
// use messagebox to give user feedback
int howManySucceed = listToUpdate.Count - failedOrderIDs.Count;
MessageBox.Show((howManySucceed == 0 ? "" : howManySucceed.ToString() + " order(s) updated.\n") +
(failedOrderIDs.Count == 0 ? "" : failedOrderIDs.Count + " order(s) failed to update. " + failMsg));
// if there are failed updates, add them to listToUpdate again, fetch newest data from database, so user can try to update again
if (failedOrderIDs.Count > 0)
{
var updateFailedOrders = new List <Order>();
foreach (var failedOrderID in failedOrderIDs)
{
foreach (var order in listToUpdate)
{
if (order.OrderID == failedOrderID)
{
updateFailedOrders.Add(order);
}
}
}
listToUpdate = updateFailedOrders;
// fetch newest data, bind to orders, so that data on form is up to date
allOrders = OrderDB.GetOrders();
orderBindingSource.DataSource = allOrders;
// if current order is not in update list, hide date change indicators
if (!listToUpdate.Contains(currentOrder))
{
grpDateChangeVisualIndicator.Visible = false;
lblDateChangeTextIndicator.Visible = false;
}
}
else // if all updated successfully, clear update list, disable save
{
listToUpdate.Clear();
// save button is only enabled when there are unsaved changes in listToUpdate
orderBindingNavigatorSaveItem.Enabled = false;
grpDateChangeVisualIndicator.Visible = false;
lblDateChangeTextIndicator.Visible = false;
}
}
catch (Exception ex)
{ // if exception is thrown, show error message
MessageBox.Show("Updates failed due to " + ex.Message, ex.GetType().ToString());
}
}