Duplicate values removal using Javascript

Question

var arr1=["a","b","b","c","c","d"];
var arr2=["b","c",];

arr1 has duplicate values which are listed in arr2. Now I want to remove the duplicate values from arr1 using arr2. Is it possible?

http://stackoverflow.com/questions/13486479/javascript-array-unique — Asif, Sep 26 '13 at 06:00
Visit this link http://stackoverflow.com/questions/14930516/compare-two-javascript-arrays-and-remove-duplicates — , Sep 26 '13 at 06:06

Joe Simmons · Answer 1 · 2013-09-26T06:24:19.313

1

I would use the Array's .filter() method.

arr1 = arr1.filter(function (val) {
    return arr2.indexOf(val) === -1;
});

For IE8 or earlier, this code should work:

arr1 = arr1.filter(function (val) {
    var i;
    for (i = 0; i < arr2.length; i += 1) {
        if ( val === arr2[i] ) {
            return false;
        }
    }
    return true;
});

edited Sep 26 '13 at 06:24

answered Sep 26 '13 at 06:03

Joe Simmons

1,828
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12
9

Property or Method indexOf is undefined... – Pearl Sep 26 '13 at 06:09
Works fine for me on `Firefox 23.0.1`. What does your browser say if you do this? `alert(Array.prototype.indexOf);` ? If it alerts a function, my code should work. If not... that's really weird because filter and indexOf were added in the same version of JavaScript. – Joe Simmons Sep 26 '13 at 06:12
`The indexOf() method is not supported in Internet Explorer 8 and earlier.` – Deepak Ingole Sep 26 '13 at 06:15
1

try this if the browser is – joydesigner Sep 26 '13 at 06:21
Ah... then why is `.filter()` supported? Weird. I updated my answer for the asker, for IE8 and earlier. – Joe Simmons Sep 26 '13 at 06:24
Did you test this on a page with any libraries? That might have been why - I'm pretty sure that IE8 doesn't have `.filter()` natively. – Qantas 94 Heavy Sep 26 '13 at 07:01

score 1 · Answer 2 · answered Sep 26 '13 at 06:39

you can use directly to remove duplicates from array1 as

 $(document).ready(function(){
     var arr1=["a","b","b","c","c","d"];
     var arr2=[];   

     $.each(arr1, function(i,el){
            if($.inArray(el, arr2) === -1) 
                arr2.push(el);
           });
      alert(arr2);
   });

you can observe here..

http://jsfiddle.net/nPeaV/7410/

Duplicate values removal using Javascript

2 Answers2