MOP works well as a safety net to catch message passing errors, but that's not its most interesting function.

MOP 就像一个安全网，捕捉传递错误的消息，但是这不是它最妙的功能。

youdao

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。

youdao