PHP实现根据银行卡号判断银行

header('content-type:text/html;charset=utf-8'); 
require_once('banklist.php'); 
function bankinfo($card,$banklist) 
{ 
  $card_8 = substr($card, 0, 8); 
  if (isset($banklist[$card_8])) { 
    echo $banklist[$card_8]; 
    return; 
  } 
  $card_6 = substr($card, 0, 6); 
  if (isset($banklist[$card_6])) { 
    echo $banklist[$card_6]; 
    return; 
  } 
  $card_5 = substr($card, 0, 5); 
  if (isset($banklist[$card_5])) { 
    echo $banklist[$card_5]; 
    return; 
  } 
  $card_4 = substr($card, 0, 4); 
  if (isset($banklist[$card_4])) { 
    echo $banklist[$card_4]; 
    return; 
  } 
  echo '该卡号信息暂未录入'; 
} 
 
bankinfo('6228481552887309119',$banklist);