jQuery.merge()

Categories: Utilities

jQuery.merge( first, second )Returns: Array

Description: Merge the contents of two arrays together into the first array.

The $.merge() operation forms an array that contains all elements from the two arrays. The orders of items in the arrays are preserved, with items from the second array appended. The $.merge() function is destructive. It alters the length and numeric index properties of the first object to include items from the second.

If you need the original first array, make a copy of it before calling $.merge(). Fortunately, $.merge() itself can be used for this duplication:

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var newArray = $.merge([], oldArray);

This shortcut creates a new, empty array and merges the contents of oldArray into it, effectively cloning the array.

Prior to jQuery 1.4, the arguments should be true Javascript Array objects; use $.makeArray if they are not.

Examples:

Example 1

Merges two arrays, altering the first argument.

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$.merge( [ 0, 1, 2 ], [ 2, 3, 4 ] )

Result:

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[ 0, 1, 2, 2, 3, 4 ]

Example 2

Merges two arrays, altering the first argument.

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$.merge( [ 3, 2, 1 ], [ 4, 3, 2 ] )

Result:

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[ 3, 2, 1, 4, 3, 2 ]

Example 3

Merges two arrays, but uses a copy, so the original isn't altered.

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var first = [ "a", "b", "c" ];
var second = [ "d", "e", "f" ];
$.merge( $.merge( [], first ), second );

Result:

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[ "a", "b", "c", "d", "e", "f" ]