php-Arrays function-array_diff-calculate the difference set of arrays_PHP tutorial

array_diff() function calculates the difference set of arrays

【Function】
This function will return an array,
This array contains all values ​​in array1 that are not in any other parameter array.
                              Note that the key names of the original array remain unchanged.
【Scope of use】
            php4 > 4.0.1, php5.
【Use】
array array_diff( array array1, array array2[,array...] )
           array1/required/array1
           array2/required/comparable array must have at least one
           array.../optional/array used for comparison
【Example】
[php]
//Define two arrays respectively
$array1 = array( "blue" => 6, "red" => 2, "green" => 3, "purple" => 4 );
$array2 = array( "green" => 5, "blue" => 6, "yellow" => 7, "cyan" => 8 );
print_r( array_diff( $array1, $array2 ) );
/*
Array
(
[red] => 2
[green] => 3
[purple] => 4
)
*/

Excerpted from zuodefeng’s notes