I have an array and I want to put it in another array using indexes.
For example:
arry[1].push(sub_array_1)
array[2].push (sub_array_2)
But I get an error if I write:
var sub_array_1 = [1, 2, 2, 2, 2];
arry[1].push(sub_array_1)
5 Answers
Using spread operator
var subArray = [1, 4, 6, 7];
var mainArray = [6, 7, 8];
var index = 1;
mainArray = [...mainArray.slice(0, index), subArray, ...mainArray.slice(index)];
Comments
Assuming:
var arry = [9,8,7];
var sub_array_1 = [1,2,2,2,2];
If you are trying to insert
sub_array_1intoarry, as a single element, just usesplicedirectly:arry.splice(1, 0, sub_array_1);The result will be:
[9,[1,2,2,2,2],8,7]On the other hand, if you are trying to insert the contents of
sub_array_1before the second element ofarry, you can do something like this:Array.prototype.splice.apply(arry, [1, 0].concat(sub_array_1));
The result will be:
[9,1,2,2,2,2,8,7]Here is a more general function:
function insert(arrayDest, index, arraySrc) { Array.prototype.splice.apply(arrayDest, [index, 0].concat(arraySrc)); }[EDITED]
Starting with ES6, you can simplify the above code using the spread operator (
...). For example:function insert(arrayDest, index, arraySrc) { arrayDest.splice(index, 0, ...arraySrc); }
3 Comments
slebetman
Since
arry is an array why not just us arry.splice()?
cybersam
Because
splice expects the inserted elements to be passed as individual values, not as an array.slebetman
Ah. I think your understanding of the question is wrong. He wants to insert the sub_array into the array. Not the contents of sub_array. If you feel that your interpretation is correct please ask the OP to clarify.
You're using wrong syntax! Follow the either below mentioned approach.
var sub_array_1 = [1,2,2,2,2];
arry[1] = sub_array_1;
// OR
var sub_array_1 = [1,2,2,2,2];
arry.push(sub_array_1);
.push(ele) will add an item to an array, thereby incrementing the length of array by 1. Remember array index starts at 0.
If you need to add an item(array/object/other) to a particular index, use [index]. Eg: arry[0] = [1,23]; arry[1] = [4,5,6,7];
1 Comment
softvar
Hope it solves your problem :) Please mark it answer by ticking :)
let array = []
array.push({"index": 0, "value":100})
console.log(array)maybe it helping for you
Comments
obj.arrayOne.push(arrayLetters);
or
obj['arrayOne'].push(arrayLetters);
arryandarray?Array#pushand array element access.pushwhich is easily answered by RTFM.