如果希望Tcp服务器端可以与多个客户端连接，可以这样写：

    tcpServer=new QTcpServer(this);connect(tcpServer,SIGNAL(newConnection()),this,SLOT(onNewConnection()));

void MainWindow::onNewConnection()
{QTcpSocket *tcpSocket;//TCP通讯的SockettcpSocket = tcpServer->nextPendingConnection(); //创建socketqDebug()<<"tcpSocket:"<<tcpSocket;connect(tcpSocket, SIGNAL(connected()),this, SLOT(onClientConnected()));emit tcpSocket->connected();connect(tcpSocket, SIGNAL(disconnected()),this, SLOT(onClientDisconnected()));connect(tcpSocket,SIGNAL(stateChanged(QAbstractSocket::SocketState)),this,SLOT(onSocketStateChange(QAbstractSocket::SocketState)));emit tcpSocket->stateChanged(tcpSocket->state());connect(tcpSocket,SIGNAL(readyRead()),this,SLOT(onSocketReadyRead()));
}

相关的槽函数中：

void MainWindow::onClientConnected()
{//客户端接入时QTcpSocket* tcpSocket=(QTcpSocket*)sender();ui->plainTextEdit->appendPlainText("**client socket connected");ui->plainTextEdit->appendPlainText("**peer address:"+tcpSocket->peerAddress().toString());ui->plainTextEdit->appendPlainText("**peer port:"+QString::number(tcpSocket->peerPort()));
}

使用sender()来获取对应的QTcpSocket对象。

其实，主要就是QTcpServer进行监听：

客户端的QTcpSocket与服务器端的QTcpSocket进行通信。