Question:
You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create a custom control named OrderForm. You write the following code segment.
public delegate void
CheckOrderFormEventHandler(EventArgs e);
private static readonly object CheckOrderFormKey
= new object();
public event CheckOrderFormEventHandler
CheckOrderForm {
add {
Events.AddHandler(CheckOrderFormKey, value);
}
remove {
Events.RemoveHandler(CheckOrderFormKey,
value);
}
}
You need to provide a method that enables the OrderForm control to raise the CheckOrderForm event. Which code segment should you use?
A
protected virtual void OnCheckOrderForm(EventArgs e) { CheckOrderFormEventHandler checkOrderForm =
(CheckOrderFormEventHandler)Events[
typeof(CheckOrderFormEventHandler)];
if (checkOrderForm != null)
checkOrderForm(e);
}
B
protected virtual void OnCheckOrderForm(EventArgs e) { CheckOrderFormEventHandler checkOrderForm =
Events[CheckOrderFormKey] as CheckOrderFormEventHandler; if (checkOrderForm != null)
checkOrderForm(e);
}
C
CheckOrderFormEventHandler checkOrderForm =
new CheckOrderFormEventHandler(checkOrderFormCallBack); protected virtual void OnCheckOrderForm(EventArgs e) { if (checkOrderForm != null)
checkOrderForm(e);
}
D
CheckOrderFormEventHandler checkOrderForm =
new CheckOrderFormEventHandler(checkOrderFormCallBack); protected virtual void OnCheckOrderForm(EventArgs e) { if (checkOrderForm != null)
RaiseBubbleEvent(checkOrderForm, e);
}
+ AnswerB
+ Report