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From JSON string to JSON object



  • I want to convert JSON strings into JSON objects which I can use in C++. I know of QJsonValue and QJsonObject, I'm probably just using them wrong.

    As an example I am passing a const char* which points to:

        [{"failure":"onFileError",
             "file":["~/XMLMPAM/config/simon.txt", "wt"],
               "op":"open",
          "success":"onFileWrite"},
          {"binary":[10,11,12 ],
               "op":"write",
             "text":"123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ\r\n"},
            {"name":"simon",
               "op":"save"},
          {"binary":[10,11,12 ],
               "op":"write",
             "text":"123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ\r\n"},
            {"name":"simon",
               "op":"restore"},
          {"binary":[25,27,28 ],
               "op":"write",
             "text":"HELLO"},
              {"op":"close"}]
    

    The above is an array of objects. I start of by creating an instance of QJsonValue:

        QJsonValue valJSON(cpszJSON);
    

    I then test for it being an array or an object:

        if ( valJSON.isArray() == true || valJSON.isObject() == true ) {
            objJSON = valJSON.toObject();
        }
    

    It doesn't pass either of these tests, I've validated that the JSON string I'm passing is of the correct syntax, why does it fail and is there a way to do this?

    I used http://json.parser.online.fr to verify the syntax.


  • Qt Champions 2019

    See ctor of QJsonValue(const char*) - it creates a new JSon value with the given string. There is nothing about parsing.
    You're looking for QJsonDocument::fromJson()


  • Qt Champions 2019

    See ctor of QJsonValue(const char*) - it creates a new JSon value with the given string. There is nothing about parsing.
    You're looking for QJsonDocument::fromJson()


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