javascript : Merge two arrays into one

Question

Say for example I have an array

arr = [
 1, 2, 3
 4, 5, 6
]

Instead, I would like to use aliases for each line Ex.

var a = [ 1, 2, 3 ];
var b = [ 4, 5, 6 ];

Where

arr = [
 a,
 b
]

should be the same as the original arr.

Yet the current example gives back [ [1,2,3],[4,5,6] ] instead

How would I achieve something like this in javascript?

• Tomanow: Javascript is not a whitespace sensitive language, line breaks will not matter.
• thefourtheye: Didn't arr = [ a, b ] work?
• dk123: @thefourtheye arr = [a, b] results in [ [1,2,3],[4,5,6]]
• thefourtheye: @dk123 What exactly do you want? I couldn't understand that from the question. Can you please explain clearly with an example?
• ReallyMadeMeThink: Please clarify "it isn't at the moment since I would be inserting arrays instead of actual numbers of lists"

Answer 1

Use Array::concat():

var a = [ 1, 2, 3 ];
var b = [ 4, 5, 6 ];
var c = [ 7, 8, 9 ];
var arr = Array.concat(a,b,c);
alert(arr); // 1,2,3,4,5,6,7,8,9

http://jsfiddle.net/9ys2ow0y/1/

Answer 2

"should be the same as the original arr." NO!!!

The concat() method is used to join two or more arrays.

This method does not change the existing arrays, but returns a new array, containing the values of the joined arrays.

var a = [ 1, 2, 3 ];
var b = [ 4, 5, 6 ];
arr = a.concat(b); //or Array.concat(a,b);
console.log(a);//[1,2,3]
console.log(b);//[4,5,6]
console.log(arr);//[1,2,3,4,5,6]