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PHP array_merge() Function

Definition and Usage

The array_merge() function merges one ore more arrays into one array.

Syntax

array_merge(array1,array2,array3...)

Parameter	Description
array1	Required. Specifies an array
array2	Optional. Specifies an array
array3	Optional. Specifies an array

Tips and Notes

Tip: You can assign one array to the function, or as many as you like.

Note: If two or more array elements have the same key, the last one overrides the others.

Note: If you assign only one array to the array_merge() function, and the keys are integers, the function returns a new array with integer keys starting at 0 and increases by 1 for each value. (See example 2)

Example 1

<?php
$a1=array("a"=>"Horse","b"=>"Dog");
$a2=array("c"=>"Cow","b"=>"Cat");
print_r(array_merge($a1,$a2));
?>

The output of the code above will be:

Array ( [a] => Horse [b] => Cat [c] => Cow )

Example 2

Using only one array parameter.

<?php
$a=array(3=>"Horse",4=>"Dog");
print_r(array_merge($a));
?>

The output of the code above will be:

Array ( [0] => Horse [1] => Dog )

Complete PHP Array Reference