Object Manipulation Object

manipulate-object.js

function getByPath(object, path) {
    var keys = path.replace('[', '.').replace(']', '').split('.');
    var last = keys.length - 1;
    var obj = object;

    for (var i = 0; i < last; i++) {
        var prop = keys[i];
        if (!obj[prop]) return undefined;
        obj = obj[prop];
    }

    return obj[keys[last]];
}

function setByPath(object, path, value) {
    var keys = path.replace('[', '.').replace(']', '').split('.');
    var last = keys.length - 1;
    var obj = object;

    for (var i = 0; i < last; i++) {
        var prop = keys[i];
        if (!obj[prop]) obj[prop] = {};
        obj = obj[prop];
    }

    obj[keys[last]] = value;
    return object;
}

// Examples

/*
var snack = {
    id: '0',
    name: 'Cake',
    batters: {
        batter: [{
            id: '0',
            type: 'Regular'
        }, {
            id: '1',
            type: 'Chocolate'
        }, {
            id: '2',
            type: 'Blueberry'
        }]
    },
    hello: []
};
*/


/*
console.log(getByPath(snack, 'id')); // --> '0' 
console.log(getByPath(snack, 'batters.batter').length); // --> '3'
console.log(getByPath(snack, 'batters.batter.2.id')); // --> '2'
console.log(getByPath(snack, 'batters.batter[1].id')); // --> '1'
*/

/*
setByPath(snack, 'id', 1); // --> 1
setByPath(snack, 'batters.batter.2.id', 2); // --> 2
setByPath(snack, 'batters.batter[1].id', 1); // --> 1
setByPath(snack, 'hello.0', 'world'); // --> 'world'
setByPath(snack, 'foo.bar', 'new'); // --> 'new'
*/