通过一串点表示法在对象文字中设置深度？

Question

There are plenty of solutions out there to check/access an object literal giving a string of dot notation, but what I need to do is SET an object literal based on a string of dot notation. It is very technical why I need to do this, and if it isn't feasible I will come up with a different solution.

Here is what I'd like to do:

var obj = { 
   'a': 1, 
   'b': 2, 
    'c': { 
      'nest': true 
    } 
};

I'd like a function that would work something like this:

setDepth(obj, 'c.nest', false);

That would change the obj to this:

var obj = { 
   'a': 1, 
   'b': 2, 
    'c': { 
      'nest': false
    } 
};

I've been trying to an hour and haven't been able to come up with a good solution yet. Another help would be so greatly appreciated!

Answer 1

My version:

function setDepth(obj, path, value) {
    var tags = path.split("."), len = tags.length - 1;
    for (var i = 0; i < len; i++) {
        obj = obj[tags[i]];
    }
    obj[tags[len]] = value;
}

Working demo: http://jsfiddle.net/jfriend00/Sxz2z/

Answer 2

This is one way of doing it:

function setDepth(obj, path, value) {
    var levels = path.split(".");
    var curLevel = obj;
    var i = 0;
    while (i < levels.length-1) {
        curLevel = curLevel[levels[i]];
        i++;
    }
    curLevel[levels[levels.length-1]] = value;
}

Working demo.

Answer 3

I modified Elliot's answer to let it add new nodes if they don't exist.

 var settings = {}; function set(key, value) { /** * Dot notation loop: http://stackoverflow.com/a/10253459/607354 */ var levels = key.split("."); var curLevel = settings; var i = 0; while (i < levels.length-1) { if(typeof curLevel[levels[i]] === 'undefined') { curLevel[levels[i]] = {}; } curLevel = curLevel[levels[i]]; i++; } curLevel[levels[levels.length-1]] = value; return settings; } set('this.is.my.setting.key', true); set('this.is.my.setting.key2', 'hello');

Answer 4

Just do it like this:

new Function('_', 'val', '_.' + path + ' = val')(obj, value);

In your case:

var obj = { 
   'a': 1, 
   'b': 2, 
    'c': { 
      'nest': true 
    } 
};

new Function('_', 'val', '_.c.nest' + ' = val')(obj, false);