Javascript: how to join two arrays [duplicate]

Question

I know this has been asked a lot of times, but I cannot get it to work.

I have an empty array a

var a = [];

and an array with an object b

var b = [{
   title: 'test'
}]

I want to join them so a will look exactly like b. The idea is to do this inside a for loop so a would be added a new item each time.

By using a.concat(b), a results in an empty array.

Not sure what I am missing.

Nick G · Accepted Answer · 2016-11-17 14:35:33Z

4

This method does not change the existing arrays, but instead returns a new array.

You need to assign this operation back to a

a = a.concat(b)

answered Nov 17, 2016 at 14:35

Nick G

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Comments

ps-aux · Accepted Answer · 2016-11-17 14:34:52Z

1

You need to assign result of that call to a. a = a.concat(b)

answered Nov 17, 2016 at 14:34

ps-aux

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