c++ - QNetworkReply::error 信号什么时候会跟着一个 finish() 信号？

Question

对于信号:

QNetworkReply::error(QNetworkReply::NetworkError code)

Qt 的文档说:

This signal is emitted when the reply detects an error in processing. The finished() signal will probably follow, indicating that the connection is over.

具体来说，finished()信号什么时候发出，什么时候不发出？

Answer 1

When will QNetworkReply::error signal followed by a finished() signal? To be specific, when will the finished() signal be emitted and when not?

信号finished()在请求由于数据传输完成或传输过程中发生错误而完成时发出。如果发生错误，信号 error() 会在 finished() 之前发生。在实践中，我们可以处理“错误”和“传输成功”的finished()。

举例说明:

// connect 'finished' signal with consumer
connect(&s_networkAccessManager, SIGNAL(finished(QNetworkReply*)),
        this, SLOT(requestFinished(QNetworkReply*)));



void MyClass::requestFinished(QNetworkReply* pReply)
{
    if ( pReply )
    {
         if (pReply->error() == QNetworkReply::NoError)
             consumeData(pReply)
         else
             errorHandler(pReply->error(), pReply->errorString());
    }
}