Given an associative array containing array elements and the task is to remove a key and its value from the associative array.
Examples:
Input : array( "name" => "Anand", "roll"=> "1")
Output : Array (
[roll] => 1
)
Input : array( "1" => "Add", "2" => "Multiply", "3" => "Divide")
Output : Array (
[2] => Multiply
[3] => Divide
)
Method 1: Using unset() function: The unset() function is used to unset a key and its value in an associative array.
Syntax:
void unset( $array_name['key_to_be_removed'] )
Program:
<?php   // Declare an associative array $arr = array(     "1" => "Add",     "2" => "Multiply",     "3" => "Divide");   // Remove the key 1 and its value // from associative array unset($arr['1']);   // Display the array elements print_r($arr);   ?> |
Output:
Array
(
[2] => Multiply
[3] => Divide
)
Method 2: Using array_diff_key() function: This function is used to get the difference between one or more arrays. This function compares the keys between one or more arrays and returns the difference between them.
Syntax:
array array_diff_key( $array_name, array_flip((array) ['keys_to_be_removed'] )
Program:
<?php   // Declare an associative array $arr = array(     "1" => "a",     "2" => "b",     "3" => "c");   // Remove the key 1 and its value // from associative array $result = array_diff_key($arr,             array_flip((array) ['1']));   // Display the result print_r($result);   ?> |
Output:
Array
(
[2] => b
[3] => c
)
