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Json-string inside a qml function possible?



  • Hello,
    I will create a Json-string inside a qml function.
    but then I get the error Expected token `,' How i can fix this.
    I define the JsonString outside as a property var jsonString then inside the function i set the content to this variable.
    function add(){
    .......................
    ................
    jsonString = '{"Theoryname": ""+ rythmusname +"", "URL1": ""+ url1 +"", "URL2":"" + url2 +"","URL3": ""+ url3}';
    Component.onCompleted: {
    var JsonObject= JSON.parse(jsonString);
    //retrieve values from JSON again
    var aString = JsonObject.Theoryname;
    var bString = JsonObject.URL1;
    var cString = JsonObject.URL2;
    var dString = JsonObject.URL3;
    console.log(aString);
    console.log(bString);
    console.log(cString);
    console.log(dString);
    }
    }
    Is this correct, and can this work?



  • Also if i make the Component.onCompleted: {...} outside the function and the var jsonString inside the function to set the content.
    came the error ---> JSON.parse: Parse error .
    How I can fix this, if it is better to set the Component.onCompleted: {...} out
    The error came between
    var JsonObject= JSON.parse(jsonString);
    //retrieve values from JSON again
    var aString = JsonObject.Theoryname;
    Component.onCompleted: {

    				var JsonObject= JSON.parse(jsonString);
    				//retrieve values from JSON again
    				var aString = JsonObject.Theoryname;
    				var bString = JsonObject.URL1;
    				var cString = JsonObject.URL2;
    				var dString = JsonObject.URL3;
    
    				console.log(aString);
    				console.log(bString);
    				console.log(cString);
    				console.log(dString);
                                      }

  • Moderators

    @Sam009 said in Json-string inside a qml function possible?:

    can this work?

    Yes. If you try a simpler string, it will work:

    jsonString = '{"key": "value"}'
    var JsonObject = JSON.parse(jsonString);

    '{"Theoryname": ""+ rythmusname +"", "URL1": ""+ url1 +"", "URL2":"" + url2 +"","URL3": ""+ url3}'

    This is not a valid JSON string. To see why, call console.log(jsonString)



  • Hi @JKSH
    I made console.log(jsonString) and i get this string {"Theoryname": ""+ rythmusname +"", "URL1": ""+ url1 +"", "URL2":"" + url2 +"","URL3": ""+ url3}

    Then i have to make jsonString = {"Theoryname": " th1", "URL1": "url1", "URL2": " url2 " ,"URL3": "url3"} , Then it works if i make it define it directly and not with values.

    But i can define the jsonString inside the function and the var JsonObject = JSON.parse(jsonString); is outside the function? (in another fucntion)

    Thx i will try this.


  • Moderators

    @Sam009 said in Json-string inside a qml function possible?:

    But i can define the jsonString inside the function and the var JsonObject = JSON.parse(jsonString); is outside the function? (in another fucntion)

    Yes you can.

    Thx i will try this.

    You're welcome. Good luck!



  • @JKSH

    Yes this works, thx.

    A smal question: How to define a Jason string array in qml. and also how to call it later. For example the first elment with his content?
    Give it in qml a for loop , for the Jason string array?


  • Moderators

    @Sam009 said in Json-string inside a qml function possible?:

    A smal question: How to define a Jason string array in qml. and also how to call it later. For example the first elment with his content?
    Give it in qml a for loop , for the Jason string array?

    Hi, I'm don't quite understand your question. Can you show an example of what you want?



  • @JKSH
    I will create a json array and there i will save multipe elements. And this elments i will call later to get the content of the first element, or the second. But if i do this (code) i get the error JSON.parse: Parse error. How i can fix this and also is it possiblel to create a array in that way?

    function add(){
    .......................
    ................

    switch (listrythmus.rh1) {
    case 1: settings.jsonString[settings.jsonid] = '{"Rythmusname": "1", "URL1": "url1", "URL2":"url2","URL3": "url3"}'; break;
    case 2: settings.jsonString[settings.jsonid] = '{"Rythmusname": "2 string", "URL1": "url1", "URL2":"url2","URL3": "url3"}'; break;
    case 3: settings.jsonString[settings.jsonid] = '{"Rythmusname": "3", "URL1": "url1", "URL2":"url2","URL3": "url3"}'; break;
    case 4: settings.jsonString[settings.jsonid] = '{"Rythmusname": "4", "URL1": "url1", "URL2":"url2","URL3": "url3"}'; break;
    case 5: settings.jsonString[settings.jsonid] = '{"Rythmusname": "5", "URL1": "url1", "URL2":"url2","URL3": "url3"}'; break;
    case 6: settings.jsonString[settings.jsonid] = '{"Rythmusname": "6", "URL1": "url1", "URL2":"url2","URL3": "url3"}'; break;
    default: pluginDialog.close(); break;
    }
    jsonStringfunctheory()
    console.log(settings.jsonString)

    }
    function jsonStringfunc{
    Component.onCompleted; {
    var JsonObject= JSON.parse(settings.jsonString);
    //Error JSON.parse: Parse error
    for(var i=0;i<settings.jsonid;i++){

    				//retrieve values from JSON again
    				var aString = JsonObject.Rythmusname[settings.jsonid];
    				var bString = JsonObject.URL1[settings.jsonid];
    				var cString = JsonObject.URL2[settings.jsonid];
    				var dString = JsonObject.URL3[settings.jsonid];
    
                                        /*var aString = settings.jsonString.Rythmusname[settings.jsonid];
    				var bString = settings.jsonString.URL1[settings.jsonid];
    				var cString = settings.jsonString.URL2[settings.jsonid];
    				var dString = settings.jsonString.URL3[settings.jsonid];*/
    
    				console.log(aString)
    				console.log(bString)
    				console.log(cString)
    				console.log(dString)                                    }
                                      }	
                                     settings.jsonid ++
                                    update(Dialog)
                                    }
    

    jsonid is a extern variable store in the settings. it is the index.


  • Moderators

    @Sam009 said in Json-string inside a qml function possible?:

    settings.jsonString[settings.jsonid] = '{"Rythmusname": "1", "URL1": "url1", "URL2":"url2","URL3": "url3"}';
    

    Well, even though you named your variable jsonString, you did not create a string. You created an array.

    You cannot pass an array into JSON.parse(); you can only pass a string.

    Make sure you understand this:

    // v1 is an array
    var v1 = [];
    v1[0] = 42;
    v1[1] = "Hello";
    
    // v2 is a string
    var v2 = '[42, "Hello"]';
    
    // v3 is an array that is has the same value as v1
    var v3 = JSON.parse(v2);
    

    Anyway, let's step back first: Why do you want to create JSON strings? Why not just use plain JavaScript objects and JavaScript arrays?



  • @JKSH
    The idea is to create many elements with tag like URL1: "...." and this has different links etc..Also the name of the tag can by change and the number of tags this since I will make one element with "Rythmusname": "1", "URL1": "url1", "URL2":"url2","URL3": "url3" and a second "Typename": "1", "notename": "1", "URL1": "url1", "URL2":"url2","URL3": "url3". And I don´t know how to store this. So was the idea to create a Jason array/string that has all this and I will make a set of object that I can call later into an outer function. But I can only make one time the JSON. parse () and so a second so a second element get not store. (that was the idea to make an array and so it was "easier" to call a set/object with JsonObject.URL1 [id of the set]) But this don´t work give it a better solution?
    {
    "id": 1,
    "Typename": "1"
    "notename": "2"
    "URL1": "url1",
    "URL2":"url2",
    "URL3": "url3"
    },
    {
    "id": 2,
    "Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    },
    {
    "id": 3,
    Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    }
    Or is it better to create more Json to store the different content, so that I have one for Rythmusname and Typename/notename. Into the settings I make the property very jsonString: [] them into the function I call it. But this is wrong since JSON. parse (v2) will create an Array of string (v2), if I understand the example with v3. Then I change jsonString: [] to jsonString. But then I can´t store more as one object/set.
    How I can make that it store more elements that I can call later by here Id?I hope it is understandable, and I'm sorry for the many questions.


  • Moderators

    You don't need JSON strings for this.

    @Sam009 said in Json-string inside a qml function possible?:

    {
    "id": 1,
    "Typename": "1"
    "notename": "2"
    "URL1": "url1",
    "URL2":"url2",
    "URL3": "url3"
    },
    {
    "id": 2,
    "Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    }

    var obj1 = {};
    obj1["id"] = 1; // NOTE: This is the same as ` obj1.id = 1`
    obj1["Typename"] = "1";
    obj1["notename"] = "2";
    obj1["URL1"] = "url1";
    obj1["URL2"] = "url2";
    obj1["URL3"] = "url3";
    
    var obj2 = {};
    obj2["id"] = 2;
    obj2["Rythmusname"] = "Rythmusname";
    obj2["Url1"] = "1";
    obj2["Url2"] = "2";
    obj2["Url3"] = "3";
    
    console.log(obj1.Typename)
    console.log(obj2.Rhythmusname)
    


  • @JKSH
    Ok and how I can it dynamically so that it can create more as 1 from the same. Since the idea is to create a X of number of them and save this. And later call them individually. (without to create multiple obj1... or jsaonstring)
    If a I create a 2 theory then the previous information is not overwritten.
    I've done it with Json-string, but I can only do one time "var JsonObject = JSON.parse (settings.jsonString);" , and if i set a 2 element (2 theorie) is no longer saved.
    How do I can create more than one element of theorie and save it?


  • Moderators

    @Sam009 said in Json-string inside a qml function possible?:

    Ok and how I can it dynamically so that it can create more as 1 from the same. Since the idea is to create a X of number of them and save this. And later call them individually. (without to create multiple obj1... or jsaonstring)
    If a I create a 2 theory then the previous information is not overwritten.
    I've done it with Json-string, but I can only do one time "var JsonObject = JSON.parse (settings.jsonString);" , and if i set a 2 element (2 theorie) is no longer saved.
    How do I can create more than one element of theorie and save it?

    I'm sorry, I don't understand your description.

    Here's a way to dynamically create Objects and put them into Arrays. I hope it helps:

    Code

    var array = [];
    for (var i = 0; i < 3; ++i)
    {
        var obj = {};
        obj["id"] = i;
        obj["url"] = "url" + i;
    
        array.push(obj);
    }
    
    console.log(array)
    

    Output

    [ { id: 0, url: 'url0' },
      { id: 1, url: 'url1' },
      { id: 2, url: 'url2' } ]
    


  • Based on the answer of JKSH, it is not a valid string so you need to log this.



  • @JKSH
    ---- First create an Object, then parse into a Json.------------------

    if i make a object like :
    objRhytmus["id"] = 12; objRhytmus["Rythmusname"] = "th1"; objRhytmus["URL1"] = "Link"; objRhytmus["URL2"] = "Link"; objRhytmus["URL3"] = "Link";

    Then var json2 = JSON.stringify(objRhytmus); this object is now a Json-string and how i can call the emelent "id" with objRhytmus["id"]
    Then i make a JSON.parse(json2) . to get a Json-string, but is this still like this:
    [
    {
    "id": 1,
    "Typename": "1"
    "notename": "2"
    "URL1": "url1",
    "URL2":"url2",
    "URL3": "url3"
    },
    {
    "id": 2,
    "Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    },
    {
    "id": 3,
    Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    }
    ]

    And if i call the id of one set then i can get the whole set with this id, or is it now a string?
    But can I make this multiple time so that the previously element is still there and not override. Or how i can do that i have more as one set of this object/set?


  • Moderators

    @Sam009 said in Json-string inside a qml function possible?:

    This is the first part of your code:

    if i make a object like :
    objRhytmus["id"] = 12; objRhytmus["Rythmusname"] = "th1"; objRhytmus["URL1"] = "Link"; objRhytmus["URL2"] = "Link"; objRhytmus["URL3"] = "Link";

    This is the 2nd part of your code:

    Then var json2 = JSON.stringify(objRhytmus); this object is now a Json-string and how i can call the emelent "id" with objRhytmus["id"]
    Then i make a JSON.parse(json2) . to get a Json-string, but is this still like this:
    [
    {
    "id": 1,
    "Typename": "1"
    "notename": "2"
    "URL1": "url1",
    "URL2":"url2",
    "URL3": "url3"
    },
    {
    "id": 2,
    "Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    },
    {
    "id": 3,
    Rythmusname": "Rythmusname"
    "Url1": "1"
    "Url2": "2"
    "Url3": "3"
    }
    ]

    Can you please update your example? Make the first part match the second part. Otherwise, it is difficult for me to understand what you want.



  • @JKSH
    Hi, I'm sorry for the late answer. Thanks for your help, I find out a solution. And for the moment it works :) I made an "object array" obj [n] = {"id": Val, "url": "url"}And n is the value of the id., and it is the set number.
    And if I will set a new element to this val I take the val of id and put the new element (the with different element names.) on it. obj[n] = { "id" : val, "url2": "url"}. so at the object with the id = x get a new value.
    And I use jsonstring = JSON. stringify (obj); to make a json object of all object[].


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