Copy array items into another array

javascript arrays
bba picture bba · Nov 11, 2010 · Viewed 1.1M times · Source

I have a JavaScript array dataArray which I want to push into a new array newArray. Except I don't want newArray[0] to be dataArray. I want to push in all the items into the new array:

var newArray = [];

newArray.pushValues(dataArray1);
newArray.pushValues(dataArray2);
// ...

or even better:

var newArray = new Array (
   dataArray1.values(),
   dataArray2.values(),
   // ... where values() (or something equivalent) would push the individual values into the array, rather than the array itself
);

So now the new array contains all the values of the individual data arrays. Is there some shorthand like pushValues available so I don't have to iterate over each individual dataArray, adding the items one by one?

Answer

WiseGuyEh picture WiseGuyEh · Nov 11, 2010

Use the concat function, like so:

var arrayA = [1, 2];
var arrayB = [3, 4];
var newArray = arrayA.concat(arrayB);

The value of newArray will be [1, 2, 3, 4] (arrayA and arrayB remain unchanged; concat creates and returns a new array for the result).

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