Using array_search I get error

This array comes from $_REQUEST of all data submitted $array='Array ( [id] => 17 [takeaction] => saveCustomFields [notes] => -- Feb 4, 2007 @ 9:16 PM --fdsfdsfsdfdsfsfsfds -- Feb 4, 2007 @ 9:21 PM --fdfdsfsdffsd -- February 11, 2007, @ 9:31 PM -- This is a tes -- February 14, 2007, @ 10:10 PM -- jhafjhfa afjahfajfhda kasjdaksdhADSKJL [firstname] => NANCY [lastname] => ADKINS [phone2] => [address1] => 25 ALWARD CT. [address2] => [city] => MARTINSVILLE [State] => AK [other] => [zip] => 24112 [country] => US [date18] => 03-13-2007 [text19] => test1 [text20] => [rating] => 0 [status] => Active )'; when I use array_search to find date18 $key = array_search('date18', $array); // $key = 1; I get Wrong datatype for second argument How come the array is wrong datatype isn't a array an array or am I using this wrong