php从银行卡号中获取银行信息

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';
}