Check if object does not exists in array, and if not push to it

Question

Okay, I've tried several examples found on stackoverflow on my example and nothing worked for me as I wanted. I have an array with 12 object in it which looks like this

var buttons = [ {"tag":"adr","color":"#123456"},
           {"tag":"ag","color":"#123456"},
           {"tag":"fax","color":"#123456"},
           {"tag":"ind","color":"#123456"},
           {"tag":"sname","color":"#123456"},
           {"tag":"per","color":"#123456"},
           {"tag":"tel","color":"#123456"},
           {"tag":"url","color":"#123456"},
           {"tag":"url","color":"#123456"},
           {"tag":"weblink","color":"#123456"},
           {"tag":"weblink","color":"#123456"},
           {"tag":"close","color":"#123456"} ];

and I wanna push this to another array var buttonsP if it is not in that array already. I tried (among other examples) with jquery .grep option:

var buttonsP =[];

for (var i = 0; i < buttons.length; i++){

    var newObject = { "valueTagP": buttons[i].tag, "colorTagP": buttons[i].color };    
    if( $.grep(buttonsP, function(obj) { return obj.valueTagP != buttons[i].tag; }) ){
        buttonsP.push(newObject);
    }
}

for (var i = 0; i < buttonsP.length; i++){
    $(".list").append("<li>"+ buttonsP[i].valueTagP + ", " + buttonsP[i].colorTagP +"</li>");
}

But duplicates were not removed.

You can check and edit my situation here: http://jsfiddle.net/M4mA9/

What am I doing wrong?

@Cerbrus That did not work for me because I have objects in array, not values. I've tried to modify just that example but I lost myself — dzordz, Jan 31 '14 at 12:53
Plz check http://stackoverflow.com/questions/6680430/get-unique-results-from-json-array-using-jquery — Bhavesh Parekh, Jan 31 '14 at 12:57

score 2 · Accepted Answer · answered Jan 31 '14 at 13:05

$.grep will return the matched array based on the condition. You see the details at http://api.jquery.com/jquery.grep/

Your code should be like

    var newObject = { "valueTagP": buttons[i].tag, "colorTagP": buttons[i].color };   
    var newArr = $.grep(buttonsP, function(obj) {             
        return obj.valueTagP === buttons[i].tag; 
    });
    if(newArr.length === 0) {
        buttonsP.push(newObject);
    }

I modified your code and updated the fiddle

that will work for me, thank you :) – dzordz Jan 31 '14 at 13:08 — dzordz, Jan 31 '14 at 13:08

score 1 · Answer 2 · answered Jan 31 '14 at 13:03

I am assuming buttonsP contains only buttons.

In that case,

instead of making buttons an array, make it an object as

var buttons = {key : "some_unique_key",
               value: /*put your buttons array here*/}

now buttonsP will contain buttons object (not an buttons array)

Now you can easily find buttons object in your array based on the key (make sure it is unique) and insert if it is not there.

score 1 · Answer 3 · answered Jan 31 '14 at 13:06

1

var buttonsP = $.grep(buttons, function (obj, i) {
    var m = buttons.filter(function (v) {
        return v.tag === obj.tag;
    })[0];
    return $.inArray(m, buttons) === i;
});

http://jsfiddle.net/f22dv/

answered Jan 31 '14 at 13:06

Ram

143,282
16
168
197

nice example too, but I accepted faster one, don't get mad :) – dzordz Jan 31 '14 at 13:09

score 0 · Answer 4 · answered Jan 31 '14 at 12:55

0

If you may use JQuery, try it:

var a1 = ["Cecilie", "Lone"];
var a2 = ["Cecilie", "Emil"];
var b = $.unique($.merge($.merge([], a1), a2));

answered Jan 31 '14 at 12:55

iury

118
5

`$.unique()` only works for DOM elements. It's used by jQuery internally. – Ram Jan 31 '14 at 13:07
and yet, it works! http://jsfiddle.net/LfZ55/ – iury Jan 31 '14 at 13:14
Yes, your demo works, from `$.unique` documentation, "_Sorts an array of DOM elements, in place, with the duplicates removed. Note that this only works on arrays of DOM elements, not strings or numbers._" :) – Ram Jan 31 '14 at 13:17

Check if object does not exists in array, and if not push to it

4 Answers4