PHP array_unique() Function
PHP array_unique() Function
The array_unique() function in PHP removes the duplicate values from the specified array.
Syntax
array_unique (array $array [, int $sort_flags = SORT_STRING])
Parameter
array(required)- This array represents the first input array.
sort_flags (optional)- This parameter is used to modify the sorting behavior. The various sorting type flags are as follows:
- SORT_REGULAR – It compares the items normally (don't change types)
- SORT_NUMERIC – It compares the items numerically
- SORT_STRING (Default Value) – It compares the items as strings
- SORT_LOCALE_STRING – It compares the items as strings, based on the current locale.
Return
This function returns the filtered array by removing the duplicate values for the array.
Example 1
Output
Input Array: Array ( [0] => green [1] => red [2] => green [3] => blue [4] => red ) Unique Array: Array ( [0] => green [1] => red [3] => blue )
Example 2
"23", "B"=>"45","C"=> "45", "D"=>"21", "E"=>"90"); echo("Input Array: \n"); print_r($array); //return the unique array by removing the duplicate elements $result = array_unique($array,SORT_NUMERIC );//will compare the items numerically echo("\nUnique Array: \n"); print_r($result); ?>
Output
Input Array: Array ( [A] => 23 [B] => 45 [C] => 45 [D] => 21 [E] => 90 ) Unique Array: Array ( [A] => 23 [B] => 45 [D] => 21 [E] => 90 )
Example 3
"1", "B"=>"2","C"=> 1, "D"=>2, "E"=>3); echo("Input Array: \n"); print_r($array); //return the unique array by removing the duplicate elements $result = array_unique($array,SORT_NUMERIC);//will compare the items as numeric echo("\nUnique Array: \n"); //will return 1,2,3 as it will compare the items as numeric print_r($result); ?>
Output
Input Array: Array ( [A] => 1 [B] => 2 [C] => 1 [D] => 2 [E] => 3 ) Unique Array: Array ( [A] => 1 [B] => 2 [E] => 3 )
Example 4
"Apple", "B"=>"Apple","C"=> "Mango", "D"=>"mango", "E"=>"banana"); echo("Input Array: \n"); print_r($array); //return the unique array by removing the duplicate elements $result = array_unique($array,SORT_STRING );//will compare the items as string echo("\nUnique Array: \n"); print_r($result); ?>
Output
Input Array: Array ( [A] => Apple [B] => Apple [C] => Mango [D] => mango [E] => banana ) Unique Array: Array ( [A] => Apple [C] => Mango [D] => mango [E] => banana )
Example 5
"@", "B"=>"@","C"=> "$", "D"=>"%", "E"=>"$"); echo("Input Array: \n"); print_r($array); //return the unique array by removing the duplicate elements $result = array_unique($array,SORT_LOCALE_STRING);//will compare the items as string,based on the current locale echo("\nUnique Array: \n"); print_r($result); ?>
Output
Array ( [A] => @ [C] => $ [D] => % )