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How should post data to API that has ContentTypeHeader:"text/plain; charset=utf-8" ?

  • I use this link to find API ContentTypeHeader

    this line:

    qDebug() << reply->header(QNetworkRequest::ContentTypeHeader).toString();

    print :

    "text/plain; charset=utf-8"

    so for post data I do like:

    QNetworkRequest request(QUrl(""));
    request.setHeader(QNetworkRequest::ContentTypeHeader, "text/plain; charset=utf-8");
     QByteArray const data("145,2018/02/16,19:17:23");
     QNetworkAccessManager nam;
     QNetworkReply *reply =, data);


    QNetworkRequest request(QUrl(QStringLiteral("")));
     request.setHeader(QNetworkRequest::ContentTypeHeader, QStringLiteral("text/plain; charset=utf-8"));
    QString text(QStringLiteral("145,2018/02/16,19:17:23"));
    QByteArray const data = text.toUtf8();
    QNetworkAccessManager nam;
    QNetworkReply *reply =, data);

    But the server replied:

    Unsupported Media Type

    where is the problem?

  • Lifetime Qt Champion


    From the looks of it, you are trying to send the wrong kind of data to that end point. You should check its documentation to see what it expects.

    The fact that it replies with text has nothing to do with what is valid to send to it.

  • This post is deleted!

  • @SGaist am I get the correctly contentTypeheader With that link ?

  • And am I use contentTypeHeader correctly?

  • Lifetime Qt Champion

    Did you check what the endpoint you are sending requests to requires ?

  • Can you show us an example of valid request to your API? Maybe using curl?

    Qt tutorials from should be avoided, they are of very low quality and sometimes encourage toxic patterns in code.

  • @SGaist @VRonin I send post request with postman in google chrome
    I set header Content-Type:"application/json"
    in body section I choose raw
    and data:"122,2019/02/21,10:54:31"
    data is successfully posted to the API and I can see it on the URL


    I change my code :

     QNetworkRequest request(QUrl(""));
    request.setRawHeader("Content-Type", "application/json");
       QByteArray data("102,2018/02/16,19:17:23");
        QNetworkAccessManager nam;
        QNetworkReply *reply =, data);

    I do not get any errors, but when I check the URL, the data is not post(set)on it

  • Lifetime Qt Champion

    Except that what you send is not valid JSON.

  • @SGaist but I post the same format data that I use in postman

    POST /api/PatData/ HTTP/1.1
    Content-Type: application/json
    Cache-Control: no-cache
    Postman-Token: c31beda7-12bf-d5b8-4945-88895d0727a0

  • Lifetime Qt Champion

    You should check the data sent using postman.

  • I checked the C code in postman the data format must be :

    QByteArray data("\"185,2019/02/22,10:59:21\"");

    Finally it's post successfuly :-/

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