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PHP array_unique() Function

PHP Array Reference Complete PHP Array Reference

Definition and Usage

The array_unique() function removes duplicate values from an array. If two or more array values are the same, the first appearance will be kept and the other will be removed.

Syntax

array_unique(array)

Parameter Description
array Required. Specifying an array

Tips and Notes

Note: The returned array will keep the first array item's key type.

Example

<?php
$a=array("a"=>"Cat","b"=>"Dog","c"=>"Cat");
print_r(array_unique($a));
?>

The output of the code above will be:

Array ( [a] => Cat [b] => Dog )

PHP Array Reference Complete PHP Array Reference

From http://www.w3schools.com (Copyright Refsnes Data)