Sort array by value from sub-array item

Question

Im trying to sort the items from an object/array by their "name" item,

I used this page for reference Sort array of objects and build the piece of code below:

var alphabet = {
    a: 1,
    b: 2,
    c: 3,
    d: 4,
    e: 5,
    f: 6,
    g: 7,
    h: 8,
    i: 9,
    j: 10,
    k: 11,
    l: 12,
    m: 13,
    n: 14,
    o: 15,
    p: 16,
    q: 17,
    r: 18,
    s: 19,
    t: 20,
    u: 21,
    v: 22,
    w: 23,
    x: 24,
    y: 25,
    z: 26
}

var test = {
    item: {
        name: "Name here",
        email: "example@example.com"
    },

    item2: {
        name: "Another name",
        email: "test@test.com"
    },

    item3: {
        name: "B name",
        email: "test@example.com"
    },

    item4: {
        name: "Z name",
        email: "example@text.com"
    }
};
test.sort(function (a, b) {return alphabet[a.name.charAt(0)] - alphabet[b.name.charAt(0)]});

console.log(test);

Unfortunately no errors are returned and the console.log doesn't returns anything either. Any help is greatly appreciated!

EDIT: After the answer has been given, it seemed the variable "test" was required to be an array, however, the variable was generated dynamically in an external library, therefor I made this little piece of code. If anyone has the same issue, feel free to use it.

var temp = [];
$.each(test, function(index, value){
    temp.push(this);
});

//temp is the resulting array

There is no `sort` method for Objects--only Arrays! If you want to sort the object, your best bet is probably to map the keys in test to an Array and call `sort` from there. — rjz, Apr 15 '12 at 23:34
You are only sorting by the first letter. Multiple names with the same first letter will sort semi-randomly. Is that what you want? — Marcelo Cantos, Apr 15 '12 at 23:50

score 4 · Accepted Answer · edited Apr 16 '12 at 02:36

4

test is an object, not an array. Perhaps you want this:

var test = [
    {
        name: "Name here",
        email: "example@example.com"
    },
    ⋮
];

If you need the item, item1, … to be retained against each object, you could add them as fields of each object:

var test = [
    {
        id: "item",
        name: "Name here",
        email: "example@example.com"
    },
    ⋮
];

To sort alphabetically, you need a case-insensitive comparator (and forget the alphabet object):

compareAlpha = function(a, b) {
  a = a.name.toUpperCase(); b = b.name.toUpperCase();
  return a < b ? -1 : a > b ? 1 : 0;
};

edited Apr 16 '12 at 02:36

xorinzor

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answered Apr 15 '12 at 23:37

Marcelo Cantos

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isnt the compareAlpha function doing almost the same as the current marked answer? – xorinzor Apr 15 '12 at 23:52
@xorinzor: No, it's comparing the entire string (not just the first character) and doesn't rely on an `alphabet` object. – Marcelo Cantos Apr 15 '12 at 23:53

score 1 · Answer 2 · answered Apr 15 '12 at 23:38

1

Firstly, test should be an array, not an object. Secondly, I think you are missing a call to .toLowerCase() after selecting the character.

test.sort(function (a, b) {
    return alphabet[a.name.charAt(0).toLowerCase()] - alphabet[b.name.charAt(0).toLowerCase()];
});

answered Apr 15 '12 at 23:38

pbeardshear

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Ah yes, I indeed forgot the .toLowerCase() function, it is working perfect now! – xorinzor Apr 15 '12 at 23:43

Sort array by value from sub-array item

2 Answers2