Question

i have an object sample data:

[Object, Object, Object]
  0: Object
    test_id: "1"
    area: "high"
  1: Object
    test_id: "1"
    area: "saw"
  2: Object
    test_id: "2"
    area: "look"

i am trying to create a new object by grouping by test_id.

var obj = new Object();
$.each(data, function(k, v){
    obj[v.test_id] += {area: v.area};
});

this doesn’t seem to work, it returns only one object line…

i am trying to get something like:

1: {
    {area: "high"}
    {area: "saw"}
}
2: {
    {area: "look""
}

any ideas? thanks

Answer 1

After your edit I notice something, you’re trying to create a javascript object with a property with no name, this is not the format. In JSON (javascript object notation) each property must have a value, what you are trying to store better fits an array.

Instead, push it into an array

    $.each(data, function(k, v){
    obj[v.test_id].area.push(v.area);
});

just remember to create obj[v.test_id] first and to set its area property to [].
This results in:

1: {
    area: ["high","saw"]
}
3: {
    area: ["look"]
}

Also, if you’re willing to consider using underscore it has very powerful (yet basic) collection methods, you might want to have a look at http://underscorejs.org/#groupBy