The constructor is used to form a delegate over a target object and a function pointer.

这构造器用来通过一个目标对象和一个函数指针形成一个委托。

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The delegating object keeps a reference to the other object, the delegate, and at the appropriate time sends a message to it.

委托对象保持对另一个对象的引用，委托方法在恰当的时间向其发送消息。

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This delegate simply returns the newly instantiated object and leaves the construction logic up to the client supplying the delegate.

该委托只是返回刚刚实例化的对象，而将构建逻辑留待提供该委托的客户端完成。

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