Use one array of strings to splice another array?

Question

So I have one array:

var array1 = ['one', 'two', 'three', 'four', 'five']

And another:

var array2 = ['two, 'four']

How can I remove all the strings from array2 out of array1?

Possible duplicate of What is the fastest or most elegant way to compute a set difference using Javascript arrays? — user5201742
– user5201742, Commented Apr 7, 2016 at 8:33

Nina Scholz · Accepted Answer · 2016-04-07 08:30:19Z

4

Just use Array#filter() and Array#indexOf() with bitwise not ~ operator for checking.

~ is a bitwise not operator. It is perfect for use with indexOf(), because indexOf returns if found the index 0 ... n and if not -1:
value  ~value   boolean
-1  =>   0  =>  false
 0  =>  -1  =>  true
 1  =>  -2  =>  true
 2  =>  -3  =>  true
 and so on 

var array1 = ['one', 'two', 'three', 'four', 'five'],
    array2 = ['two', 'four'];

array1 = array1.filter(function (a) {
    return !~array2.indexOf(a);
});

document.write("<pre>" + JSON.stringify(array1, 0, 4) + "</pre>");

edited Apr 7, 2016 at 8:30

answered Apr 7, 2016 at 8:24

Nina Scholz

388k26 gold badges367 silver badges417 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Rayon Over a year ago

And what about !~ ?

A. Wolff Over a year ago

@RayonDabre bitwise negation operator, making code quite unreadable imho

Lewis · Accepted Answer · 2016-04-07 08:22:42Z

2

Try this.

array2.forEach(item => array1.splice(array1.indexOf(item),1));

answered Apr 7, 2016 at 8:22

Lewis

15k14 gold badges70 silver badges88 bronze badges

Comments

ZaoTaoBao · Accepted Answer · 2016-04-07 08:33:38Z

0

in jquery with inArray method:

for(array1)
  var idx = $.inArray(array1[i], array2);
  if (idx != -1) {//-1 not exists 
     array2.splice(idx, 1);
  }

}

answered Apr 7, 2016 at 8:33

ZaoTaoBao

2,6152 gold badges22 silver badges28 bronze badges

Comments

xcodebuild · Accepted Answer · 2016-04-07 08:40:33Z

0

var array1 = ['one', 'two', 'three', 'four', 'five']
var array2 = ['two', 'four']
    
array1 = array1.filter(function(item){
   return array2.indexOf(item) === -1
})
// ['one', 'three', 'four', 'five']

document.write(array1)

answered Apr 7, 2016 at 8:40

xcodebuild

1,22910 silver badges19 bronze badges

Collectives™ on Stack Overflow

Use one array of strings to splice another array?

4 Answers 4

2 Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

2 Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related