//3. Raise Event QuitBid
private void OnEndBid(BidEventInfo e)
{
if (QuitBid != null)
{
QuitBid(this, e);
}
}
//3. Raise Event
public void OnNewBid(BidEventInfo e)
{
if (NewBid != null)
{
NewBid(this, e);
}
}
//2. Determine when to raise the event.
//Note: The arguments here, neither the sender, nor the e is of any interest for us,
//as these two belong to the button-click event.
//We create a bidInfo (correspondng to e) object and the sender is "this".
private void btnSubmit_Click(object sender, RoutedEventArgs e)
{
decimal newBid = ToDecimal.GetDecimal(txtAmount.Text);
BidEventInfo bidInfo = new BidEventInfo(this.Title, newBid);
OnNewBid(bidInfo); //Rais event
}
//2. When to raise EndBid event
private void btnQuit_Click(object sender, RoutedEventArgs e)
{
if (MessageBox.Show("You'll not be able to place a bid through this session. Continue?",
"Think twice", MessageBoxButton.YesNo) == MessageBoxResult.Yes)
{
BidEventInfo bidInfo = new BidEventInfo(this.Title, 0.0m);
OnEndBid(bidInfo);
}
}
/// <summary>
/// Here is the power of delegates - who is the bidder - don't know,
/// the sender tells us at run time
/// Eventhandler for the sender's (bidder's) SendQuitBid event - what to do when the event is
/// fired by the publisher object (a bidder class, see above)
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
///
private void OnBidderDrawBack(object sender, BidEventInfo e)
{
lstBidHistory.Items.Add(string.Format("{0} draws back at {1}. Please come back!",
e.Bidder, DateTime.Now.ToShortTimeString()));
if (sender != null)
{
BidderIsPublisher frm = (BidderIsPublisher)sender;
//Unubscribe to the publisher's new bid and quit bid events
//Compare with above (subscription)
frm.NewBid -= OnNewBidSent;
frm.QuitBid -= OnBidderDrawBack;
frm.Title = "You are out! " + DateTime.Now.ToShortTimeString();
}
}
//###############################################################################
/// <summary>
/// From this line on no information available on the bidder that is just created.
/// Here is the power of delegates - who is the bidder - don't know,
/// the sender tells us at run time
///
/// Eventhandler for the SendNewBid event - what to do when the event is
/// fired by the publisher object (a bidder class, see above)
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void OnNewBidSent(object sender, BidEventInfo e)
{
if (!AcceptBid())
{
return;
}
string strError = "<= current amount - not valid! ";
string strOut = string.Format("{0} places a new bid {1,0:f2}", e.Bidder, e.Amount);
if (!CheckIfbidisValid(e.Amount))
{
strOut += strError;
}
else
{
m_currentAmount = e.Amount;
}
lstBidHistory.Items.Add(strOut);
}
