Create an object out of dot notation

Question

This is a reverse question to this question.

Given an object x={a:1,b:2} and a string c.d=3, modify object x to the following:

Answer 1

What about this :

function setObj (str, value, obj) {
    var ref = obj, keys = str.split('.');
    while (keys.length) {
        var currentKey = keys.shift();
        ref[currentKey] = keys.length ? (ref[currentKey]  ? ref[currentKey] : {}) : value;
        ref = ref[currentKey];
    }
}

Example with an input object using (could be some form values extracted with $.serializeArray)

var serializedInputs = [
    {name: 'fruits[1][name]', value: 'Banana'},
    {name: 'fruits[1][id]', value: '1'},
    {name: 'fruits[2][name]', value: 'Strawberry'},
    {name: 'fruits[2][id]', value: '2'},
    {name: 'fruits[3][name]', value: 'Raspberry'},
    {name: 'fruits[3][id]', value: '3'},
    {name: 'fruits[4][name]', value: 'Kiwi'},
    {name: 'fruits[4][id]', value: '4'},
    {name: 'fruits[5][name]', value: 'Mango'},
    {name: 'fruits[5][id]', value: '5'},
    {name: 'selected_fruit_id', value: '1'},
]
// This variable holds the result
var obj = {}
serializedInputs.forEach(function(item) {
    // Turning square brackets into dot notation
    setObj(item.name.replace(/\]/g, '').replace(/\[/g, '.'), item.value, obj);
})

Result

{
    "fruits": {
        "1": {
            "name": "Banana",
            "id": "1"
        },
        "2": {
            "name": "Strawberry",
            "id": "2"
        },
        "3": {
            "name": "Raspberry",
            "id": "3"
        },
        "4": {
            "name": "Kiwi",
            "id": "4"
        },
        "5": {
            "name": "Mango",
            "id": "5"
        }
    },
    "selected_fruit_id": "1"
}