How to remove duplicate values ​​in php

In PHP, you can use the "array_unique()" function to remove duplicate values. The function of this function is that when the values ​​​​of several array elements are equal, only the first element is retained, and the other elements are deleted. The syntax is "array_unique(array)".

php remove duplicate values

array_unique() function definition and usage

## The #array_unique() function is used to remove duplicate values ​​from an array. If two or more array values ​​are the same, only the first value is retained and the other values ​​are removed.

Note: The retained array will retain the key type of the first array item.

Syntax

array_unique(array)

Parameters

array required. Specifies an array.

sortingtype Optional. Specifies the sorting type. Possible values:

SORT_STRING - Default. Treat each item as a string.

SORT_REGULAR - Sort each item in regular order (Standard ASCII, does not change type).

SORT_NUMERIC - Treat each item as a number.

SORT_LOCALE_STRING - Treat each item as a string, based on the current locale (can be changed via setlocale()).

Example:

When the values ​​of several array elements are equal, only the first element is retained, and the other elements are deleted.

The key names in the returned array remain unchanged.

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

Output:

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

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