## 例

`

     array array_diff_key ( array $array1 , array $array2 [, array $... ] )

`

## 説明

Compares the keys from array1 against the keys from array2 and returns the difference. This function is like array_diff() except the comparison is done on the keys instead of the values.

## 戻り値

Returns an array containing all the entries from array1 whose keys are not present in any of the other arrays.