qt版的TCP客户端代码

以下是一个基本的QT TCP客户端代码示例：

#include <QtNetwork>
#include <QtWidgets>

class TcpClient : public QDialog
{
    Q_OBJECT

public:
    TcpClient(QWidget *parent = nullptr);

private slots:
    void start();
    void stop();
    void readData();
    void displayError(QAbstractSocket::SocketError socketError);

private:
    QLabel *hostLabel;
    QLineEdit *hostLineEdit;
    QLabel *portLabel;
    QLineEdit *portLineEdit;
    QLabel *statusLabel;
    QPushButton *startButton;
    QPushButton *stopButton;
    QTcpSocket *tcpSocket;
    QTextEdit *textEdit;
};

TcpClient::TcpClient(QWidget *parent)
    : QDialog(parent), tcpSocket(new QTcpSocket(this))
{
    hostLabel = new QLabel(tr("Host name:"));
    hostLineEdit = new QLineEdit("127.0.0.1");
    portLabel = new QLabel(tr("Port number:"));
    portLineEdit = new QLineEdit("8080");
    statusLabel = new QLabel(tr("Status: Not connected"));
    startButton = new QPushButton(tr("Connect"));
    stopButton = new QPushButton(tr("Disconnect"));
    textEdit = new QTextEdit;
    textEdit->setReadOnly(true);

    QGridLayout *mainLayout = new QGridLayout(this);
    mainLayout->addWidget(hostLabel, 0, 0);
    mainLayout->addWidget(hostLineEdit, 0, 1);
    mainLayout->addWidget(portLabel, 1, 0);
    mainLayout->addWidget(portLineEdit, 1, 1);
    mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
    mainLayout->addWidget(startButton, 3, 0);
    mainLayout->addWidget(stopButton, 3, 1);
    mainLayout->addWidget(textEdit, 4, 0, 1, 2);

    stopButton->setEnabled(false);

    connect(startButton, SIGNAL(clicked()), this, SLOT(start()));
    connect(stopButton, SIGNAL(clicked()), this, SLOT(stop()));
    connect(tcpSocket, SIGNAL(readyRead()), this, SLOT(readData()));
    connect(tcpSocket, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(displayError(QAbstractSocket::SocketError)));
}

void TcpClient::start()
{
    QString host = hostLineEdit->text();
    int port = portLineEdit->text().toInt();
    tcpSocket->connectToHost(host, port);

    if (tcpSocket->waitForConnected()) {
        startButton->setEnabled(false);
        stopButton->setEnabled(true);
        statusLabel->setText(tr("Status: Connected"));
    } else {
        QMessageBox::critical(this, tr("Error"), tcpSocket->errorString());
    }
}

void TcpClient::stop()
{
    tcpSocket->disconnectFromHost();
    startButton->setEnabled(true);
    stopButton->setEnabled(false);
    statusLabel->setText(tr("Status: Not connected"));
}

void TcpClient::readData()
{
    QByteArray data = tcpSocket->readAll();
    textEdit->append(QString(data));
}

void TcpClient::displayError(QAbstractSocket::SocketError socketError)
{
    switch (socketError) {
    case QAbstractSocket::RemoteHostClosedError:
        break;
    case QAbstractSocket::HostNotFoundError:
        QMessageBox::information(this, tr("Error"), tr("The host was not found. Please check the host name and port settings."));
        break;
    case QAbstractSocket::ConnectionRefusedError:
        QMessageBox::information(this, tr("Error"), tr("The connection was refused by the peer. Make sure the fortune server is running, and check that the host name and port settings are correct."));
        break;
    default:
        QMessageBox::information(this, tr("Error"), tr("The following error occurred: %1.").arg(tcpSocket->errorString()));
    }

    startButton->setEnabled(true);
    stopButton->setEnabled(false);
    statusLabel->setText(tr("Status: Not connected"));
}

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    TcpClient client;
    client.show();
    return a.exec();
}

#include "tcpclient.moc"

该代码使用QTcpSocket类来处理TCP连接。 它创建一个简单的界面，允许用户输入服务器主机名和端口号，并包括控制连接的开始和停止按钮。 一旦连接建立，它将显示从服务器接收到的任何数据。

请注意，该代码仅是一个基本示例，可能需要根据您的特定需求进行修改。