Remove n-th elements from the end of an array

Question

I have an array like this:

array = [1,2,3,4,5,6,7,8]

and i want to remove for example the 4 last values so as my array becomes this: array = [1,2,3,4] I used array.splice(array.length - 4, 1) but it didn't work. Any ideas?

Answer 1

You can use the function slice as follow:

.slice(0, -4)

This approach doesn't modify the original Array

//                                    +---- From 0 to the index = (length - 1) - 4,
//                                    |     in this case index 3.
//                                  vvvvv
var array = [1,2,3,4,5,6,7,8].slice(0, -4);
console.log(array);

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This approach modifies the original Array

var originalArr = [1, 2, 3, 4, 5, 6, 7, 8];

//                     +---- Is optional, for your case will remove 
//                     |     the elements ahead from index 4.
//                     v
originalArr.splice(-4, 4);
console.log(originalArr);

//----------------------------------------------------------------------

originalArr = [1, 2, 3, 4, 5, 6, 7, 8];
//                  +---- Omitting the second param.
//                  |     
//                  v
originalArr.splice(-4);
console.log(originalArr);

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Docs

• Array.prototype.splice()
• Array.prototype.slice()

Answer 2

Removing 4 elements from the end a list

var myList = [1,2,3,4,5,6,7,8];
var removed = myList.splice(-myList.length-4, 4);

https://jsfiddle.net/etuf28bj/4/

Answer 3

array.splice(0,4)

will remove 0 elements from the array begin and 4 elements from array ends

Answer 4

You can also use filter for removing element(it will not modify existing array)

array = [1,2,3,4,5,6,7,8];
array1=array.filter((x,i)=>i<array.length-4);
console.log(array1);

Or you can use splice(it will change array itself)

array = [1,2,3,4,5,6,7,8];
array.splice(-4);
console.log(array);