Delegates, Events, and Lambdas
1. Specifically speaking, a delegate object maintains three important pieces of information:• The address of the method on which it makes calls
• The arguments (if any) of this method
• The return value (if any) of this method
2. When the C# compiler processes delegate types, it automatically generates a sealed class deriving from System.MulticastDelegate. This class (in conjunction with its base class, System.Delegate) provides the necessary infrastructure for the delegate to hold onto a list of methods to be invoked at a later time.
3. C# delegate definition results in a sealed class with three compiler-generated methods whose parameter and return types are based on the delegate’s declaration. The following pseudo-code approximates the basic pattern:
// This is only pseudo-code!public sealed class DelegateName : System.MulticastDelegate{public DelegateName (object target, uint functionAddress);public delegateReturnValue Invoke(allDelegateInputRefAndOutParams);public IAsyncResult BeginInvoke(allDelegateInputRefAndOutParams,AsyncCallback cb, object state);public delegateReturnValue EndInvoke(allDelegateRefAndOutParams,IAsyncResult result);}
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