40 lines
536 B
C#
40 lines
536 B
C#
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using System;
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delegate void Handler<T> (object sender);
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interface IBar<T> {
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event Handler<T> Handler;
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}
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class Foo<T> {
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IBar<T> proxy, real;
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event Handler<T> handler;
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Handler<T> proxyHandler;
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public event Handler<T> Handler {
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add {
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if (handler == null) {
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if (proxyHandler == null)
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proxyHandler = (object s) => handler (proxy);
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}
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handler += value;
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}
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remove {
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handler -= value;
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}
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}
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}
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class Program {
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public static int Main ()
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{
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var x = new Foo<int> ();
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x.Handler += null;
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return 0;
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}
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}
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