How do I create an object from an object literal in string form?

Question

In JavaScript, I can create an object like this:

var Obj = {someName:"My Name",someNumber:43};

I'm trying to do something like this (JSFiddle):

var str = '{someName:"My Name",someNumber:43}';
var Obj = new Object(str);
document.getElementById("result").innerHTML = 'Name: '+Obj.someName;

But the result will be "Name: undefined". Instead of read the notation, it crates an object with a enumerated object for each char of the string. Why? Is there a way to create an object through a description in a string?

I don't want to use the JSON format as JSON requires the use of double quotes with every property name, which is quite painful to type so often, not good to view and results in a bigger string. If possible, I wish to work with JavaScript object literal notation.

EDIT 2: this is what I'll be working on (with more time). It works for one level object, I'll think about how to make it work recursively in order to convert multidimensional objects or arrays. This question is closed so… good luck for you!

Object.defineProperty(String.prototype, "isObject", {
    enumerable: false,
    configurable: false,
    writable: false,
    value: function(){
        var string = this;
        if(string.length<=1) return false;
        return (string.charAt(0)=="{" && string.charAt(string.length-1)=="}");
    }
});
Object.defineProperty(String.prototype, "isArray", {
    enumerable: false,
    configurable: false,
    writable: false,
    value: function(){
        var string = this;
        if(string.length<=1) return false;
        return (string.charAt(0)=="[" && string.charAt(string.length-1)=="]");
    }
});
Object.defineProperty(String.prototype, "toObject", {
    enumerable: false,
    configurable: false,
    writable: false,
    value: function(){
        var string = this;
        if(!string.isObject() && !string.isArray()) return false;
        var object = string.isObject();
        string = string.slice(1,-1);
        var Obj = (object)? new Object() : new Array() ;
        var Termos = string.split(",");
        var i, Elems, n=0, val;
        for(i in Termos){
            Elems = Termos[i].split(":");
            if(Elems.length==1) {
                val = Elems[0];
                if(object){
                    Obj[n] = val;
                } else {
                    Obj.push(val);
                }
                n++;
            } else {
                if(Elems[1].isObject() || Elems[1].isArray()){
                    val = Elems[1].toObject();
                } else if(typeof(Elems[1])=="number") {
                    val = Elems[1];
                } else {
                    Elems[1] = Elems[1].replace(/['"]+/g, '');
                    val = Elems[1];
                }
                if(object){
                    Obj[Elems[0]] = val;
                } else {
                    Obj.push(val);
                }
            }
        }
        return Obj;
    }
});

You can mark as duplicated if you consider JSON as the only answer. Is it? Maybe converting to JSON so it can be parsed... — Gustavo, Nov 14 '14 at 17:36
Your code you've presented won't work with string literals that have `,` in them. ;) — Qantas 94 Heavy, Nov 23 '14 at 03:24

nicael · Accepted Answer · 2014-11-14T17:51:31.260

0

You can use

var str = '{someName:"My Name",someNumber:43}';

var strToParse = str.replace("{","").replace("}","").split(",");
for(var i = 0;i < strToParse.length;i++){strToParse[i] = '\"'+strToParse[i].split(":")[0]+'\":'+strToParse[i].split(":")[1];}

strToParse="{"+strToParse+"}";
var Obj = JSON.parse(strToParse);

edited Nov 14 '14 at 17:51

answered Nov 14 '14 at 17:22

nicael

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Is not a JSON. In JSON the var name got to be inside quotes: "someName":"My Name". JSON.parse won't work. – Gustavo Nov 14 '14 at 17:33
I was thinking about something like this, don't think there is a shorten way, but I'll wait a bit longer for other suggestions, who knows... My own solution don't use JSON, so the properties are create one by one after turn the string into an array. I'll post it later. – Gustavo Nov 14 '14 at 21:36
I mark as the right answer because it really solved the problem presented, but I think you should look the EDIT 2 of the answer, you might find it interesting. And thanks! – Gustavo Nov 18 '14 at 01:51
This doesn't have much chance of working with nested objects, string values with curly brackets or colons in them, and innumerable other cases. – Nov 23 '14 at 04:50

How do I create an object from an object literal in string form?

1 Answers1