PHP实现通过Luhn算法校验信用卡卡号是否有效

$numbers = "49927398716 49927398717 1234567812345678 1234567812345670";
foreach (split(' ', $numbers) as $n)
  echo "$n is ", luhnTest($n) "htmlcode">

49927398716 is valid
49927398717 is not valid
1234567812345678 is not valid
1234567812345670 is valid


下面是一个更为简洁的代码：

复制代码 代码如下:function luhn_test($num) {

    $str = '';

    foreach( array_reverse( str_split( $num ) ) as $i => $c ) $str .= ($i % 2 "$n is ", luhn_test($n) "</br>\n";
输出结果如下


49927398716 is valid
49927398717 is not valid
1234567812345678 is not valid
1234567812345670 is valid


希望本文所述对大家的php程序设计有所帮助。