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PO.NET4: How to apply dynamic binding to anonymous delegates with returns?
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copied!<pre><code>class MyClass { public event Action<string> OnAction; public event Func<string, int> OnFunc; } class Program { static void Main(string[] args) { MyClass mc = new MyClass(); /// I need to handle arbitrary events. /// But I see no way to create anonymous delegates in runtime /// with arbitrary returns and parameters. So I choosed to /// create multiple “signatures” with different parameter /// number (up to 10) and different returns (either the Action or /// Func). While Actions<> work pretty well, the Funcs<> do not. Action<dynamic> someAction = delegate(dynamic p1) { }; Func<dynamic, dynamic> someFunc = delegate(dynamic p1) { return 42;}; // OK mc.OnAction += someAction; // Error: “Cannot implicitly convert type 'System.Func<dynamic,dynamic>' // to 'System.Func<string,int>'” mc.OnFunc += someFunc; // It doesn't work this way as well (the same error message): // dynamic someFunc = new Func<dynamic, dynamic>((dynamic n1) => { return 42; }); // Let's try another way // 1: // Cannot convert anonymous method to delegate type 'System.Func<string,int>' // because the parameter types do not match the delegate parameter types. // 2 (even more funny): // Parameter 1 is declared as type 'dynamic' but should be 'string'. mc.OnFunc += delegate(dynamic p1) { return 42; }; } } </code></pre> <p>Why does it work for actions and doesn't for functions? In other words, I just would like to know why <code>Action<dynamic> → Action<string></code> is ok while <code>Func<dynamic,dynamic> → Func<string, int></code> is not. Thanks.</p>

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