array_diff_key 使用键名比较计算数组的差集 &reftitle.description; arrayarray_diff_key arrayarray1 arrayarray2 array ... array_diff_key 返回一个数组，该数组包括了所有出现在 array1 中但是未出现在任何其它参数数组中的键名的值。注意关联关系保留不变。本函数和 array_diff 相同只除了比较是根据键名而不是值来进行的。 1, 'red' => 2, 'green' => 3, 'purple' => 4); $array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8); var_dump(array_diff_key($array1, $array2)); ?> ]]> &example.outputs; int(2) ["purple"]=> int(4) } ]]> 在 key => value 对中的两个键名仅在 (string) $key1 === (string) $key2 时被认为相等。换句话说，执行的是严格类型检查，因此字符串的表达必须完全一样。 注意本函数只检查了多维数组中的一维。当然，可以用 array_diff_key($array1[0], $array2[0]); 来检查更深的维度。 参见 array_diff，array_udiff，array_diff_assoc，array_diff_uassoc，array_udiff_assoc，array_udiff_uassoc，array_diff_ukey，array_intersect，array_intersect_assoc，array_intersect_uassoc，array_intersect_key 和 array_intersect_ukey。 &reftitle.parameters; array1 The array to compare from array2 An array to compare against ... More arrays to compare against &reftitle.returnvalues; Returns an array containing all the entries from array1 whose keys are not present in any of the other arrays. &reftitle.examples; The two keys from the key => value pairs are considered equal only if (string) $key1 === (string) $key2 . In other words a strict type check is executed so the string representation must be the same. 1, 'red' => 2, 'green' => 3, 'purple' => 4); $array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8); var_dump(array_diff_key($array1, $array2)); ?> ]]> &example.outputs; int(2) ["purple"]=> int(4) } ]]> &reftitle.notes; This function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using array_diff_key($array1[0], $array2[0]);. &reftitle.seealso; array_diff array_udiff array_diff_assoc array_diff_uassoc array_udiff_assoc array_udiff_uassoc array_diff_ukey array_intersect array_intersect_assoc array_intersect_uassoc array_intersect_key array_intersect_ukey