How to form a nested JSON object from an array?

Question

I have a path(as a string) like

A/B/C/D

. I want to represent it as a JSON object as follows :

{
   A:{
      B:{
         C:D
      }
   }
}

Now lets say I add a path

A/B/C/X

then the JSON should look like

{
   A:{
      B:{
         C:[D,X]
      }
   }
}

So what I do is when I get the path, I split it and store in an array as follows

var struct = {};
var path = $scope.path.split("/"); //assuming $scope.path holds the path  
for(var i =0;i<path.length-1;i++)
    {
        struct[path[i]] = path[i+1];
    }

However this leads to json as {A: "B", B: "C", C: "D"}. How do I fix this? Is there a recursive way to do this?

EDIT : My previous schema would lead to error. As KevinB suggested, I am updating the schema to something like [{name: 'A', children: [{name: 'B', children: []}]}]

You can't have two identical keys in an object, so you will never get C: D and C: X in the B object, C would need to be converted to an array of [D,X], or B to be an array of [{C:D},{C:X}] — MDEV
– MDEV, Commented May 20, 2015 at 19:31
"Is there a recursive way to do this?" Yes, iterate over the path, on each iteration go one level deeper into the object until you're through the whole path. However, first you have to come up with a schema that actually works, per the previous comment. — user400654
– user400654, Commented May 20, 2015 at 19:32
Your updated schema, how then would you represent /A/B/C/D/E? or /A/Z? — user400654
– user400654, Commented May 20, 2015 at 19:33
Was thinking maybe a more normalized structure, such as [{name: 'A', children: [{name: 'B', children: []}]}] — user400654
– user400654, Commented May 20, 2015 at 19:36

Diego ZoracKy · Accepted Answer · 2015-05-20 19:50:51Z

1

Yes, take a look at this function which was created for that (i'm the author, by the way):

https://github.com/DiegoZoracKy/make-object-path

The code is:

    var makeObjectPath = function(_src, _path, _val) {

    var src = _src,
        path = _path,
        val = _val;

    if (arguments[0] instanceof Array || typeof(arguments[0]) == 'string') {
        src = {};
        path = arguments[0];
        val = arguments[1] || null;
    }

    path = (typeof(path) == 'string') ? path.split('.') : path;

    var o = src;
    var currentO = o;
    for (var i in path) {
        currentO[path[i]] = (i != path.length - 1) ? currentO[path[i]] || {} : (val) ? val : {};
        currentO = currentO[path[i]];
    }
    return o;
}

And to use it:

makeObjectPath('root.parent.child', 'someValue');

// Output:

{
    "root":{
        "parent":{
            "child":"someValue"
        }
    }
}

edited May 20, 2015 at 19:50

answered May 20, 2015 at 19:33

Diego ZoracKy

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1 Comment

Dubby Over a year ago

But if I have more than one value of say child or parent, this function will not be able to handle that. I need to create a directory structure

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