需要一些帮助,我已经完成了,但无法让它显示或正常工作。使用 str_replace,它应该获取实际的信用卡号并从中删除 - 。我已经把那部分写下来了,但是当我创建一个嵌套的 if 语句并使用 is_numeric 进行验证时,它显示“这是一个无效的卡号”;当然,如果我将其设置为 is_numeric($CreditNumber)),它也会打印出信用卡号码以及回显。
另外,我注意到一件事。我已将此文件上传到我们的类服务器,它显示信用卡号,但它显示两次,而当我使用 XAMPP 时,它根本不显示它。
有什么指点吗?这是代码
<?php
$CreditCard = array ("", "8910-1234-5678-6543", "OOOO-9123-4567-0123");
foreach ($CreditCard as $CreditNumber) {
if(empty($CreditNumber)) {
echo "Invalid Card Number <br/>";
} else {
$CreditNumber = str_replace("-", "", $CreditCard[1]);
echo $CreditNumber;
echo "<br/>";
if (is_numeric()) {
echo "This is an invalid Card Number";
} else {
echo $CreditNumber; //This shows the credit card number without the dashes
}
}
}
?>
编辑:
我已经完成了它,它在最后显示了正确的数字,但由于某些奇怪的原因,它重复了 16 位数字两次
<?php
$CreditCard = array ("", "8910-1234-5678-6543", "OOOO-9123-4567-0123");
foreach ($CreditCard as $CreditNumber) {
if(empty($CreditNumber)) {
echo "Invalid Card Number <br/>";
} else {
$CreditNumber = str_replace("-", "", $CreditCard[1]);
//echo $CreditNumber;
//echo "<br/>";
if (is_numeric($CreditCard)) {
echo "This is an invalid Card Number";
} else {
echo $CreditNumber; //This shows the credit card number without the dashes
}
}
}
?>
正则表达式在这里很有用:
$CreditCard = array("", "8910-1234-5678-6543", "OOOO-9123-4567-0123");
foreach ($CreditCard as $CreditNumber) {
if (preg_match("/^\d{4}-\d{4}-\d{4}-\d{4}$/", $CreditNumber)) {
echo "VALID: " . $CreditNumber . "\n";
}
else {
echo "INVALID: " . $CreditNumber . "\n";
}
}
打印:
INVALID:
VALID: 8910-1234-5678-6543
INVALID: OOOO-9123-4567-0123
请注意,如果您希望正则表达式模式来验证特定供应商卡(例如 Amex、Mastercard、Visa 等),请使用参考,例如这个。
在循环中,您覆盖了
$CreditCard
,因此之后无法显示原始格式。您可以使用一个短函数在作用域块中进行测试:
function isCreditNumber($creditNumber) {
if (empty($creditNumber)) {
return false;
}
$num = str_replace("-", "", $creditNumber);
if (! is_numeric($num)) {
return false;
}
return true;
}
$CreditCard = ["", "8910-1234-5678-6543", "OOOO-9123-4567-0123"];
foreach ($CreditCard as $CreditNumber) {
if (! isCreditNumber($CreditNumber)) {
echo "Invalid Card Number <br/>";
}
else {
echo $CreditNumber . " is valid<br>";
}
}
输出:
Invalid Card Number
8910-1234-5678-6543 is valid
Invalid Card Number
我们必须使用 Luhn 算法来验证信用卡号,这里是验证信用卡号的示例方法
// Function to validate a credit card number using the Luhn algorithm
function validateCreditCard($number)
{
$number = str_replace(' ', '', $number);
$sum = 0;
$numDigits = strlen($number);
$parity = $numDigits % 2;
for ($i = 0; $i < $numDigits; $i++) {
$digit = (int)$number[$i];
if ($i % 2 == $parity) {
$digit *= 2;
if ($digit > 9) {
$digit -= 9;
}
}
$sum += $digit;
}
return ($sum % 10 == 0);
}
// Example usage
$creditCardNumber = "1234567812345670"; // Replace with your credit card number
if (validateCreditCard($creditCardNumber)) {
echo "Valid credit card number.";
} else {
echo "Invalid credit card number.";
}