Qt上传文件小记

news2024/12/27 0:16:05

最近由于公司上线了云平台，需要用Qt与云平台进行对接，故拾起了network模块。

众所周知Qt网络http相关的类QNetworkAccessManager发挥着举足轻重的作用。

普通的http：GET POST PUT DELETE已经耳熟能详，网上也有很多的文章有介绍到。

今天我要说的是平时不常用的上传文件，使用的是QHttpMultiPart模块：

    QUrl url("http://xxx.xxxxxx.com/api/xxxxxx/xxxx/report");

    QHttpMultiPart* multiPart = new QHttpMultiPart(QHttpMultiPart::FormDataType);

    //form-data普通字符
    QString a                 = "TextA";
    QHttpPart aPart;
    aPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"a\""));
    aPart.setBody(a.toUtf8());

    //form-data文件
    QFile* file = new QFile("D:/xx.db");
    QString fileName = QFileInfo(*file).fileName();
    QString fileNaem_ = file->fileName();
    QHttpPart filePart;
    //warning 1
    filePart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"file\"; filename=\""+fileName+"\""));
    //warning 2
    filePart.setHeader(QNetworkRequest::ContentTypeHeader, "application/octet-stream");
    if(file->open(QIODevice::ReadOnly)) {
        filePart.setBodyDevice(file);
    }
    file->setParent(multiPart);

    //form-data文件2
    QString fileName1 = QFileInfo(*file1).fileName();
    QString fileName1_ = file1->fileName();
    QHttpPart filePart1;
    //warning 1
    filePart1.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"data\"; filename=\""+fileName1+"\""));
    //warning 2
    filePart1.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
    if(file1->open(QIODevice::ReadOnly)) {
        filePart1.setBodyDevice(file1);
    }
    file1->setParent(multiPart);


    multiPart->append(aPart);
    multiPart->append(filePart);
    multiPart->append(filePart1);

    QNetworkRequest request(url);
    QString bdry = multiPart->boundary();
    //warning 3
    request.setHeader(QNetworkRequest::ContentTypeHeader,"multipart/form-data;boundary=" + bdry);
    QNetworkReply *reply = manager->post(request, multiPart);
    connect(reply, &QNetworkReply::uploadProgress, [=](qint64 bytesSent, qint64 bytesTotal)
    {
        if ((reply->error() == QNetworkReply::NoError) &&
                (0 != bytesSent) && (0 != bytesTotal))
        {
            int uploadProgress = static_cast<int>(bytesSent * 100 / bytesTotal);

            qDebug() << "###-->" << uploadProgress << endl;
        }
    });

代码中的warning1、warning2、warning3这三个地方需要注意，基本没什么问题。

如果有问题的话，可以先用postman测试，测试OK的话，同步使用Fiddler进行抓包查看一下具体发送的数据是什么：

Postman截图：