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D E L E G AT E S, E V E N T S, A N D   L A M B D A S

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Delegates can also “point to” methods that contain any number of out or ref parameters (as

well as array parameters marked with the params keyword). For example, assume the following

delegate type:

public delegate string MyOtherDelegate(out bool a, ref bool b, int c);

The signatures of the Invoke() and BeginInvoke() methods look as you would expect; however,

check out the EndInvoke() method, which now includes the set of all out/ref arguments defined by

the delegate type:

sealed class MyOtherDelegate : System.MulticastDelegate

{

public MyOtherDelegate (object target, uint functionAddress);

public string Invoke(out bool a, ref bool b, int c);

public IAsyncResult BeginInvoke(out bool a, ref bool b, int c,

AsyncCallback cb, object state);

public string EndInvoke(out bool a, ref bool b, IAsyncResult result);

}

To summarize, a 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: