qt网络编程简易计算器代码

好的，这是一个简单的Qt网络编程计算器的代码示例：

#include <QtWidgets>
#include <QtNetwork>

class Calculator : public QWidget
{
    Q_OBJECT

public:
    Calculator(QWidget *parent = nullptr);

private slots:
    void requestNewConnection();
    void readClientData();
    void sendResult();

private:
    QTcpServer *tcpServer;
    QTcpSocket *clientSocket;
    QTextEdit *display;
    quint16 blockSize;
    QString currentOperation;
    double currentResult;
};

Calculator::Calculator(QWidget *parent)
    : QWidget(parent), tcpServer(new QTcpServer(this)), clientSocket(nullptr),
      display(new QTextEdit(this)), blockSize(0), currentOperation(""), currentResult(0.0)
{
    if (!tcpServer->listen(QHostAddress::Any, 1234)) {
        QMessageBox::critical(this, tr("Error"), tr("Unable to start the server: %1.").arg(tcpServer->errorString()));
        close();
        return;
    }

    connect(tcpServer, &QTcpServer::newConnection, this, &Calculator::requestNewConnection);

    QVBoxLayout *layout = new QVBoxLayout(this);
    layout->addWidget(display);
}

void Calculator::requestNewConnection()
{
    if (clientSocket) {
        clientSocket->disconnectFromHost();
        clientSocket->deleteLater();
    }

    clientSocket = tcpServer->nextPendingConnection();
    connect(clientSocket, &QTcpSocket::readyRead, this, &Calculator::readClientData);
}

void Calculator::readClientData()
{
    QDataStream in(clientSocket);
    in.setVersion(QDataStream::Qt_5_15);

    if (blockSize == 0) {
        if (clientSocket->bytesAvailable() < static_cast<int>(sizeof(quint16)))
            return;

        in >> blockSize;
    }

    if (clientSocket->bytesAvailable() < blockSize)
        return;

    QString operation;
    in >> operation;

    if (operation == "clear") {
        currentResult = 0.0;
        currentOperation = "";
        display->setText("");
    } else if (operation == "+" || operation == "-" || operation == "*" || operation == "/") {
        currentOperation = operation;
        currentResult = display->toPlainText().toDouble();
        display->setText("");
    } else if (operation == "=") {
        double operand = display->toPlainText().toDouble();

        if (currentOperation == "+")
            currentResult += operand;
        else if (currentOperation == "-")
            currentResult -= operand;
        else if (currentOperation == "*")
            currentResult *= operand;
        else if (currentOperation == "/")
            currentResult /= operand;

        display->setText(QString::number(currentResult));
    }

    sendResult();
}

void Calculator::sendResult()
{
    QByteArray block;
    QDataStream out(&block, QIODevice::WriteOnly);
    out.setVersion(QDataStream::Qt_5_15);

    out << static_cast<quint16>(0);
    out << display->toPlainText();
    out.device()->seek(0);
    out << static_cast<quint16>(block.size() - sizeof(quint16));

    clientSocket->write(block);
    blockSize = 0;
}

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Calculator calculator;
    calculator.show();
    return app.exec();
}

这个计算器使用TCP协议进行通信，监听端口号为1234。当客户端连接到服务器时，服务器会接收客户端发送的数据，并根据数据进行计算，然后将计算结果发送回客户端。