How to delete array value by splice?

Question

Stuck in delete array value by splice .Tried with delete and splice doesn't work..

var arr = [];
 arr[2] = 22;
 arr[5] = 3;
 arr[99] = 3343;
 for(var i in arr){
    if(i != 2){
    arr.splice(i,1);
    }
   //delete arr[i];
 }
 console.log(arr);// [2: 22, 98: 3343]
 //wanted [2:22]

I want to delete all except index 2 ,It is only delete one.

What do you mean remove array value? remove as in remove the item in the array? If you just want to empty an array you could use different ways. [See this SO post](http://stackoverflow.com/a/1232046/1504480) — Bon Macalindong, Jun 01 '16 at 03:36
`arr.length=0` ... done. First approach above `arr=[]` will break reference to original array. And don't use `for in` on an array — charlietfl, Jun 01 '16 at 03:38

score 1 · Answer 1 · answered Jun 01 '16 at 03:43

1

No need of a for loop in the splice, you may use: arr.splice(0,arr.length)

But if you want to just delete all elements just do arr=[].

Alternative method would be to loop & pop:

while(arr.length > 0) {
    arr.pop();
}

answered Jun 01 '16 at 03:43

Ani Menon

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score 0 · Answer 2 · answered Jun 01 '16 at 06:28

In the case you might need to get a sequential item by item deletion starting from the the middle of an array you should iterate in reverse in order not to get the shifting indexes get in front of you.

var arr = new Array(10).fill("").map((e,i) => e = "item:" +i),
      i = 7;
console.log(JSON.stringify(arr));
while (i>2) console.log(JSON.stringify(arr.splice(i--,1))); // splice item at index i and decrease i by one
console.log(JSON.stringify(arr));

How to delete array value by splice?

2 Answers2