Add method to JSON parsed object

Question

I have an object that is stored locally on my users PC, stringified with JSON. I noticed that when i parse it back the methods disappear. What is the most efficient way to augment an object with a method?

EDIT: Example:

var data = {
    user: {
        username: "Adam"
    }
    //function goes here
}

var myFunction = function(){/* code here*/}

This may help: [Casting plain objects to function instances (“classes”) in javascript](http://stackoverflow.com/q/11810028/218196) — Felix Kling, Dec 13 '15 at 18:52
Can you explain what you mean by "efficient" or did you just add that word for no reason? — djechlin, Dec 13 '15 at 19:02

score 2 · Answer 1 · answered Dec 13 '15 at 19:00

2

You can just assign the function to a property of the object:

var data = {
    user: {
        username: "Adam"
    }
    //function goes here
}

var myFunction = function(){/* code here*/}

data.myFunction = myFunction;

answered Dec 13 '15 at 19:00

bhspencer

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score 1 · Accepted Answer · edited Dec 13 '15 at 23:45

From my understanding of your problem, you can do like below.

var data = {
    user: {
        username: "Adam"
    },
    functionName : "myFunction"
}

var myFunction = function(){ alert("a"); }

var stringyJson = JSON.stringify(data);

var parsedJson = JSON.parse(stringyJson);

window[parsedJson.functionName]();

And if you want to pass arguments to function then add those in json and use like window[parsedJson.functionName](arg1, arg2);

Add method to JSON parsed object

2 Answers2