目录

JavaScript Array flat()

Examples

Create a new array with the sub-array elements concatenated:

const myArr = [[1,2],[3,4],[5,6]];
const newArr = myArr.flat();
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const myArr = [1, 2, [3, [4, 5, 6], 7], 8];
const newArr = myArr.flat(2);
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Description

The flat() method concatenates sub-array elements.


Syntax

array.flat( depth)

Parameters

Parameter Description
depth Optional.
How deep a nested array should be flattened.
Default is 1.

Return Value

Type Description
An array The flattened array.


Browser Support

JavaScript Array flat() is supported in all modern browsers since January 2020:

Chrome 69 Edge 79 Firefox 62 Safari 12 Opera 56
Sep 2018 Jan 2020 Sep 2018 Sep 2018 Sep 2018