根据MSDN:hEvent:IfanoverlappedI/OoperationisissuedwithoutanI/Ocompletionroutine(theoperation'slpCompletionRoutineparameterissettonull),thenthisparametershouldeithercontainavalidhandletoaWSAEVENTobjectorbenull.当我使用IOCP时，当我调用WSASend()或WSARecv()时，我将NULL传递给它们的最后一个参数(即lpCompletionRoutine):WSASend(pIoRe