How can i remove an some types of elements is js?

user_12934662 0
Viewed 62

I want to remove all of 0, false, undefined and "" elements in my list.

Here is my code:

var  a = [ 1232, "fesr", undefined,undefined, true, 0, false ,'',false , false , undefined]
console.log(a);

for(var i=0 ; i < a.length ; i++){
    if(a[i]===0 || a[i]===false || a[i]==='' || a[i]===undefined  ){
        a.splice(i,2)
    }else{
        continue
    }
}
console.log(a);

input :

[ 1232, "fesr", undefined,undefined, true, 0, false ,'',false , false , undefined]

output:

[ 1232, "fesr", true, "", undefined ]

As you see first my code does not remove "" .

second problem is it does not remove all of 0, false and undefined elements if we have a greater number of them!

How can i solve that?

arrays javascript
3 Answers

The easy way:

const data = [1232, "fesr", undefined, undefined, true, 0, false, '', false, false, undefined];
const result = data.filter(Boolean);
console.log(result)

In your code you use splice method that mutates your source array, that's why you receive incorrect result.

user_47667810

what you did was iterating over the array and then, splice by index. But if you begin in the Front, he removes first index 3 in your example, goes to the next, i is 4 now, but the next value is in 3 again. You have to do it reverse, to do it with splice by index

var  a = [ 1232, "fesr", undefined,undefined, true, 0, false ,'',false , false , undefined];
console.log(a);

for(var i = a.length - 1; i >= 0; i--){
    if (a[i] === 0 || a[i] === false || a[i] === '' || a[i] === undefined){
        a.splice(i, 1);
    } else {
        continue;
    }
}
console.log(a);
user_47214630 

const input = [ 1232, "fesr", undefined,undefined, true, 0, false ,'',false , false , undefined]

const output = []
input.forEach(item => {
  if (item) output.push(item)
})
console.log(output)

user_144776070
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