qt - QTcpSocket 未知错误

Question

我想将数据从客户端发送到服务器，当我尝试连接到 serevr 时，客户端显示未知错误，并且没有发送数据

它只显示空字符串“”，

任何帮助将不胜感激。

这是代码：

//客户

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);

    tcpSocket = new QTcpSocket(this);

    connect(tcpSocket, SIGNAL(connected()), this, SLOT(connected()));

    QHostAddress ha;
    ha.setAddress("myIP");

    tcpSocket->connectToHost(ha, 6401);

    if(!tcpSocket->waitForConnected(3000)) {
        ui->lineEdit->setText(tcpSocket->errorString());
    }
    else
        ui->lineEdit->setText("connected");
}

void Widget::connected()
{
   tcpSocket->write("hello this is client\r\n");
   tcpSocket->flush();
   tcpSocket->waitForBytesWritten(3000);

    tcpSocket->close();
}

//服务器

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);

    tcpServer = new QTcpServer(this);

    connect(tcpServer, SIGNAL(newConnection()), this, SLOT(newConnection()));

    if(!tcpServer->listen(QHostAddress::Any, 6401)) {
           ui->lineEdit->setText("server not started");
       }
       else
           ui->lineEdit->setText("server started");
}

void Widget::newConnection()
{
    QTcpSocket *tcpSocket= tcpServer->nextPendingConnection();

    qDebug() << tcpSocket->readAll();
    tcpSocket->waitForReadyRead(3000);

    tcpSocket->close();
}

Answer 1

这是问题所在：

//错误的顺序

qDebug() << tcpSocket->readAll();
tcpSocket->waitForReadyRead(3000);

//正确的顺序：

tcpSocket->waitForReadyRead(3000);
qDebug() << tcpSocket->readAll();