php - query() Dosent Work Inside a Function -

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• reference: variable scope, variables accessible , “undefined variable” errors? 3 answers

i'm making script using php , pdo syntax. , before start wanted make shortcuts me. $db->query() = qr() , $string->fetch(pdo::fetch_obj) = fet($string)

but problem pops on page, query() doesn't work inside function

( fatal error: call member function query() on non-object )

here's code

// $db->query() = qr() function qr($str) {     return $db->query($str); } // $string->fetch(pdo::fetch_obj) = fet($string) function fet($dbq) {     return $dbq->fetch(pdo::fetch_obj); }  $qr = qr("select * example"); $fet = fet($qr);  echo "".$fet->example.""; 

because $db not available in function. have pass via function parameter.

function qr($db, $str) {     return $db->query($str); } 

don't use global variable