Why using cannot be used to define a virtual function?

为什么使用不能用于定义一个虚函数?。

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This function is really a message handler, not a virtual function.

这个函数是一个真正的消息句柄，不是虚函数。

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Firstly, you should know what a virtual function is, and how to use it.

首先，你应该知道什么是虚函数，以及如何使用它。

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Unlike the expansive microcosms of Linden Lab's "Second Life" or Vivendi's "World of Warcraft, " In-Q-Tel's digital environment will likely be a single room, designed to function as a virtual meeting place for U.S. intelligence agencies, according to a Forterra spokesman.

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This means Facebook can now function as a virtual living room.

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