How Can I retrieve the number of identical values in an array in javascript?

Question

var array = ['box','box','line','time','box']

for Example : box is repeated several times

http://stackoverflow.com/questions/11246758/how-to-get-unique-values-in-a-array — Kiran, Sep 21 '13 at 07:05
http://www.codeproject.com/Tips/507855/Get-Unique-Values-from-a-JavaScript-Array — Kiran, Sep 21 '13 at 07:06
The number of unique values with duplicates? The number of times a certain value exists? Or the total number of duplicate values? — nderscore, Sep 21 '13 at 08:01

score 0 · Accepted Answer · answered Sep 21 '13 at 08:29

0

Here you go:

    var array = ['box','box','line','time','box'],
    map = {},
    key;

array.forEach(function(item) {
    if (map[item] === undefined) {
        map[item] = 1;
    } else {
        map[item]++;
    }
});

for (key in map) {
    console.log(" key:", key, " repeated:", map[key]);
}

answered Sep 21 '13 at 08:29

lastboy

566
4
12

`item in map` would be better than `=== undefined`. – georg Sep 21 '13 at 08:30

How Can I retrieve the number of identical values in an array in javascript?

1 Answers1