我想知道如何仅根据信用卡的号码来判断信用卡的类型。有谁知道确定可靠的方法吗?
当前回答
Usman Y回答的Swift 2.1版本。 使用print语句来验证，因此调用某个字符串值
print(self.validateCardType(self.creditCardField.text!))
func validateCardType(testCard: String) -> String {
let regVisa = "^4[0-9]{12}(?:[0-9]{3})?$"
let regMaster = "^5[1-5][0-9]{14}$"
let regExpress = "^3[47][0-9]{13}$"
let regDiners = "^3(?:0[0-5]|[68][0-9])[0-9]{11}$"
let regDiscover = "^6(?:011|5[0-9]{2})[0-9]{12}$"
let regJCB = "^(?:2131|1800|35\\d{3})\\d{11}$"
let regVisaTest = NSPredicate(format: "SELF MATCHES %@", regVisa)
let regMasterTest = NSPredicate(format: "SELF MATCHES %@", regMaster)
let regExpressTest = NSPredicate(format: "SELF MATCHES %@", regExpress)
let regDinersTest = NSPredicate(format: "SELF MATCHES %@", regDiners)
let regDiscoverTest = NSPredicate(format: "SELF MATCHES %@", regDiscover)
let regJCBTest = NSPredicate(format: "SELF MATCHES %@", regJCB)
if regVisaTest.evaluateWithObject(testCard){
return "Visa"
}
else if regMasterTest.evaluateWithObject(testCard){
return "MasterCard"
}
else if regExpressTest.evaluateWithObject(testCard){
return "American Express"
}
else if regDinersTest.evaluateWithObject(testCard){
return "Diners Club"
}
else if regDiscoverTest.evaluateWithObject(testCard){
return "Discover"
}
else if regJCBTest.evaluateWithObject(testCard){
return "JCB"
}
return ""
}
其他回答
这里有完整的c#或VB代码，用于各种CC相关的东西。
IsValidNumber GetCardTypeFromNumber GetCardTestNumber PassesLuhnTest
这篇文章已经发布了几年，没有任何负面评论。
Stripe提供了这个很棒的javascript库来检测卡片方案。让我添加一些代码片段，并向您展示如何使用它。
首先包括它到你的网页作为
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery.payment/1.2.3/jquery.payment.js " ></script>
其次，利用功能cardType来检测卡片方案。
$(document).ready(function() {
var type = $.payment.cardType("4242 4242 4242 4242"); //test card number
console.log(type);
});
这里有更多示例和演示的参考链接。
Stripe博客的jquery.payment.js Github库
信用卡的第一个数字可以用来大致了解供应商:
签证:49、44或47 Visa电子:42、45、48、49 万事达卡:51 美国运通:34 就餐者:30、36、38 JCB: 35
follow Luhn’s algorithm
private boolean validateCreditCardNumber(String str) {
int[] ints = new int[str.length()];
for (int i = 0; i < str.length(); i++) {
ints[i] = Integer.parseInt(str.substring(i, i + 1));
}
for (int i = ints.length - 2; i >= 0; i = i - 2) {
int j = ints[i];
j = j * 2;
if (j > 9) {
j = j % 10 + 1;
}
ints[i] = j;
}
int sum = 0;
for (int i = 0; i < ints.length; i++) {
sum += ints[i];
}
if (sum % 10 == 0) {
return true;
} else {
return false;
}
}
then call this method
Edittext mCreditCardNumberEt;
mCreditCardNumberEt.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
int cardcount= s.toString().length();
if(cardcount>=16) {
boolean cardnumbervalid= validateCreditCardNumber(s.toString());
if(cardnumbervalid) {
cardvalidtesting.setText("Valid Card");
cardvalidtesting.setTextColor(ContextCompat.getColor(context,R.color.green));
}
else {
cardvalidtesting.setText("Invalid Card");
cardvalidtesting.setTextColor(ContextCompat.getColor(context,R.color.red));
}
}
else if(cardcount>0 &&cardcount<16) {
cardvalidtesting.setText("Invalid Card");
cardvalidtesting.setTextColor(ContextCompat.getColor(context,R.color.red));
}
else {
cardvalidtesting.setText("");
}
}
@Override
public void afterTextChanged(Editable s) {
}
});
public string GetCreditCardType(string CreditCardNumber)
{
Regex regVisa = new Regex("^4[0-9]{12}(?:[0-9]{3})?$");
Regex regMaster = new Regex("^5[1-5][0-9]{14}$");
Regex regExpress = new Regex("^3[47][0-9]{13}$");
Regex regDiners = new Regex("^3(?:0[0-5]|[68][0-9])[0-9]{11}$");
Regex regDiscover = new Regex("^6(?:011|5[0-9]{2})[0-9]{12}$");
Regex regJCB = new Regex("^(?:2131|1800|35\\d{3})\\d{11}$");
if (regVisa.IsMatch(CreditCardNumber))
return "VISA";
else if (regMaster.IsMatch(CreditCardNumber))
return "MASTER";
else if (regExpress.IsMatch(CreditCardNumber))
return "AEXPRESS";
else if (regDiners.IsMatch(CreditCardNumber))
return "DINERS";
else if (regDiscover.IsMatch(CreditCardNumber))
return "DISCOVERS";
else if (regJCB.IsMatch(CreditCardNumber))
return "JCB";
else
return "invalid";
}
下面是使用Regex, c#检查信用卡类型的函数
