isset: without or with?

[eluser]Kenan[/eluser]
[quote author="jonez" date="1404687947"]If you want to check and validate specific keys I usually do this;

Code:

$data = $this->input->post( );
if ( !is_array( $data ) ) $data = array( );

if ( array_key_exists( 'q', $data ) ) {
    //clean
}

[/quote]

thanks for answer, good idea but the code will be more, because i must check a lot of keys of post data, let me wait for the other answers, if there is no other solution, i will use ur variant