QTcpSocket和QSocketNotifier

[ljq1000]

QTcpSocket和QSocketNotifier配合使用出现问题，表现为能接收到QSocketNotifier::activated(int)信号，但是从QTcpSocket中读数据时始终返回0。
代码如下：
// class TcpServer : public QTcpServer
void TcpServer::incomingConnection(qintptr socketDescriptor)
{
QString connName = ...
TcpConnectionPtr conn(new TcpConnection(connName, socketDescriptor));
......
}


TcpConnection::TcpConnection(const QString &name, qintptr sockfd)
: _name(name),
_socket(new QTcpSocket(this)),
_readNotifier(new QSocketNotifier(sockfd, QSocketNotifier::Read, this)),
_writeNotifier(new QSocketNotifier(sockfd, QSocketNotifier::Write, this)),
...
{
_socket->setSocketDescriptor(sockfd);
_socket->setSocketOption(QAbstractSocket::KeepAliveOption, 1);
_readNotifier->setEnabled(true);
_writeNotifier->setEnabled(false);

connect(_readNotifier, &QSocketNotifier::activated,
this, &TcpConnection::handleRead,
Qt::DirectConnection);
connect(_writeNotifier, &QSocketNotifier::activated,
this, &TcpConnection::handleWrite,
Qt::DirectConnection);
...
}

毫无头绪，请大家帮忙！

[ljq1000]

去掉_readNotifier，连接TCPSocket::readReady信号就可以了

[弓人水]

看下Qt帮助文档（QSocketNotifier ）：
Finally, you can use the socket() function to retrieve the socket identifier. Although the class is called QSocketNotifier, it is normally used for other types of devices than sockets. QTcpSocket and QUdpSocket provide notification through signals, so there is normally no need to use a QSocketNotifier on them.

QTcpSocket 和 QUdpSocket 自身就有readyRead()和bytesWritten(qint64 bytes)信号。

[erdoor]

@ljq1000 关于海图有问题请教，能留个联系方式吗？我的Q-Q 122-635-224