find the variable key based on its value

Question

I have the following javascript variable:

var myList =
    {
        itemA: 0,
        itemB: 1,
        itemC: 2,
        itemD: 3,
        itemE: 4
    };

I have the value of the variable, ie 0, 1, 2 etc and need to find the corresponding key to it ie if I have 2, the key would be itemC.

How can I do this with javascript?

refer this link http://stackoverflow.com/questions/784012/javascript-equivalent-of-phps-in-array — Poomalairaj, Jul 26 '11 at 14:03

score 3 · Answer 1 · answered Jul 26 '11 at 14:00

3

You'd have to iterate over every property until you find the one with that value.

for(var prop in myList) 
    if(myList[prop] == value)
       return prop;
return NOT_FOUND; // or whatever

answered Jul 26 '11 at 14:00

Ismail Badawi

36,054
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score 2 · Accepted Answer · answered Jul 26 '11 at 14:09

You can try this: http://jsfiddle.net/shaneburgess/7DzUM/

    var myList =
    {
        itemA: 0,
        itemB: 1,
        itemC: 2,
        itemD: 3,
        itemE: 4
    };

$.each(myList,function(index,value){
    if(value == 2){ alert(index); }
});

score 0 · Answer 3 · answered Jul 26 '11 at 14:01

0

if u write this like this:

 var myList =
    {
    "itemA": "0",
    "itemB": "1",
    "itemC": "2",
    "itemD": "3",
    "itemE": "4"
};

it will be a json object. then u can get itemC like this myList.itemC

answered Jul 26 '11 at 14:01

Sedat Başar

3,740
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score 0 · Answer 4 · answered Jul 26 '11 at 14:02

0

You can also loop through using the .each jQuery function if you want a pure jQuery solution. http://api.jquery.com/jQuery.each/ However, isbadawi's method would work well also.

answered Jul 26 '11 at 14:02

Nolan St. Martin

407
1
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find the variable key based on its value

4 Answers4