How to add char to javascript object keys and values?

Question

I am trying to add '_x' to every object key and '_y' to every object value. This is the code:

var data = {
  "glossary": {
    "title": "example glossary",
    "GlossDiv": {
      "title": "S",
      "GlossList": {
        "GlossEntry": {
          "ID": "SGML",
          "SortAs": "SGML",
          "GlossTerm": "Standard Generalized Markup Language",
          "Acronym": "SGML",
          "Abbrev": "ISO 8879:1986",
          "GlossDef": {
            "para": "A meta-markup language, used to create markup languages such as DocBook.",
            "GlossSeeAlso": "GMLXML"
          },
          "GlossSee": "markup"
        }
      }
    }
  }
}

function treee(data) {
  Object.keys(data).map( function (key) {
    if(Object.keys(data[key]).length == 0){
      data[key] =  {[key + "_x"]: data[key] + "_y"};
    }
    else{
      data[key] =  { [key + "_x"]: treee(data[key]) };
    }
  });
}

It is not working and I don't know why. Can you please tell what is wrong?

[JSON](http://json.org/) is a string. if you don't have a string, then it's not JSON. just something different, like an object, or an array. — Nina Scholz, Dec 06 '16 at 12:52
please **change the title** to one which describes the issue. — vsync, Dec 06 '16 at 12:53
Why the downvotes? This is a legitimate question; it just happens the OP mentions JSON, where he means Object (and that is clear from the code) — Majid Fouladpour, Dec 06 '16 at 12:57
The downvotes are probably coming because the problem is due to making some very wrong assumptions about what types of object in JavaScript come with a `length` property which would be trivial to detect with some basic debugging (i.e. by looking at what the values being tested in the `if` statements actually are). — Quentin, Dec 06 '16 at 13:00
The other reason for the downvotes is that "it is not working and I don't know why" is a very bad problem statement. — Quentin, Dec 06 '16 at 13:01
The third likely reason for downvotes is that there is no [mcve]. The `treee` function never gets called. The output never gets examined. — Quentin, Dec 06 '16 at 13:02
@zerohero There is no JSON there - it's an object. Just drop it. — Reinstate Monica Cellio, Dec 07 '16 at 07:22
@Archer won't dropping the object make his code error out? I'm confused. — zerohero, Dec 07 '16 at 07:48
@zerohero - please post what you think is JSON from the code posted above. I'll explain to you why you're wrong so you don't do the same thing again in the future :) — Reinstate Monica Cellio, Dec 07 '16 at 07:50
@Archer the entire data variable looks (and verifies) as JSON, how can it be used as an object where I can go data.glossary.GlossList.GlossEntry.ID? — zerohero, Dec 07 '16 at 07:56
@zerohero JSON is a string. It is a string representation of an object. Read more here... http://stackoverflow.com/questions/383692/what-is-json-and-why-would-i-use-it — Reinstate Monica Cellio, Dec 07 '16 at 08:46

score 2 · Accepted Answer · answered Dec 06 '16 at 13:00

2

Basically you need the new key instead of the old one and delete the actual one.

Another part is to change an inner object, if necessaray.

function treee(data) {
    Object.keys(data).map(function (key) {
        if (data[key] && typeof data[key] === 'object') {
            treee(data[key]);
        }
        data[key + '_x'] = typeof data[key] === 'string' ? data[key] + '_y' : data[key];
        delete data[key];
    });
}

var data = { glossary: { title: "example glossary", GlossDiv: { title: "S", GlossList: { GlossEntry: { ID: "SGML", SortAs: "SGML", GlossTerm: "Standard Generalized Markup Language", Acronym: "SGML", Abbrev: "ISO 8879:1986", GlossDef: { para: "A meta-markup language, used to create markup languages such as DocBook.", GlossSeeAlso: "GMLXML" }, GlossSee: "markup" } } } } };

treee(data);
console.log(data);

.as-console-wrapper { max-height: 100% !important; top: 0; }

answered Dec 06 '16 at 13:00

Nina Scholz

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Hello thanks a lot for your answer it helps me, now I would like to send and http request with the `key`, receive an answer and a add it instead of just `_x`. Can you please helps ? – theCode Dec 06 '16 at 15:27
@theCode, please add another question. – Nina Scholz Dec 06 '16 at 20:48
very sorry about that – theCode Dec 06 '16 at 22:19
'@Nina Scholz' Very sorry about that. Please accept my apologies – theCode Dec 06 '16 at 22:40
@theCode, it's ok. no need to apologise. – Nina Scholz Dec 07 '16 at 07:03

Cerbrus · Answer 2 · 2016-12-06T13:24:20.283

This is easier to do if you convert the object to JSON, then use string replacements:

var data = { "glossary": { "title": "example glossary", "GlossDiv": { "title": "S", "GlossList": { "GlossEntry": { "ID": "SGML", "SortAs": "SGML", "GlossTerm": "Standard Generalized Markup Language", "Acronym": "SGML", "Abbrev": "ISO 8879:1986", "GlossDef": { "para": "A meta-markup language, used to create markup languages such as DocBook.", "GlossSeeAlso": "GMLXML" }, "GlossSee": "markup" } } } } }

var jsonString = JSON.stringify(data),
    replacedValues = jsonString
        .replace(/([\w.])"/g, '$1_y"') // Add _y to all strings in there.
        .replace(/_y":/g, '_x":')      // Replace _y with _x for all keys.
    newData = JSON.parse(replacedValues);

console.log(newData);

Another option would be to use a regex to replace the keys, then use a reviver function to modify the values, when parsing the JSON:

var data = { "glossary": { "title": "example glossary", "GlossDiv": { "title": "S", "GlossList": { "GlossEntry": { "ID": "SGML", "SortAs": "SGML", "GlossTerm": "Standard Generalized Markup Language", "Acronym": "SGML", "Abbrev": "ISO 8879:1986", "GlossDef": { "para": "A meta-markup language, used to create markup languages such as DocBook.", "GlossSeeAlso": "GMLXML" }, "GlossSee": "markup" } } } } }

var jsonString = JSON.stringify(data)
        .replace(/":/g, '_x":');    // Add _x to all keys.

var newData = JSON.parse(jsonString, function(key, val){
    if(typeof val === 'string')     // For every value, if the value is a string
        return val + '_y';          // Add `_y`
    return val;                     // Otherwise, just return the value.
});

console.log(newData);

What's with the downvotes? Sure, it's not the "cleanest" solution, but it does exactly what the OP wants. — Cerbrus, Dec 06 '16 at 13:04
@NinaScholz: Sure, it's unconventional, but is that a reason to downvote an answer? The code works... — Cerbrus, Dec 06 '16 at 13:10
for the converting from json, the reviver could add the `_y`, but it does not work for the keys. — Nina Scholz, Dec 06 '16 at 13:11
Fun fact: This code is about ___[6 times as fast](https://jsperf.com/replace-object-keys-and-values-v2)___ as the manual implementation. (At least in Google Chrome) — Cerbrus, Dec 06 '16 at 13:17
@NinaScholz: The reviver is a good idea. I'm gonna add a option to use that. — Cerbrus, Dec 06 '16 at 13:22

How to add char to javascript object keys and values?

2 Answers2