另一个api解决方案在rapidapi银行卡位数检查有250K+发行卡类型。

只有一个GET rest api请求，并获得发卡机构信息，如:

{ "bin_number": 535177, "bank": "Finansbank A.S.", "scheme": "MASTERCARD", "type": "Debit", "country": "Turkey" }

斯威夫特 5+

extension String {
    
    func isMatch(_ Regex: String) -> Bool {
        
        do {
            let regex = try NSRegularExpression(pattern: Regex)
            let results = regex.matches(in: self, range: NSRange(self.startIndex..., in: self))
            return results.map {
                String(self[Range($0.range, in: self)!])
            }.count > 0
        } catch {
            return false
        }
        
    }
    
    func getCreditCardType() -> String? {
        
        let VISA_Regex = "^4[0-9]{6,}$"
        let MasterCard_Regex = "^5[1-5][0-9]{5,}|222[1-9][0-9]{3,}|22[3-9][0-9]{4,}|2[3-6][0-9]{5,}|27[01][0-9]{4,}|2720[0-9]{3,}$"
        let AmericanExpress_Regex = "^3[47][0-9]{5,}$"
        let DinersClub_Regex = "^3(?:0[0-5]|[68][0-9])[0-9]{4,}$"
        let Discover_Regex = "^6(?:011|5[0-9]{2})[0-9]{3,}$"
        let JCB_Regex = "^(?:2131|1800|35[0-9]{3})[0-9]{3,}$"
        
        if self.isMatch(VISA_Regex) {
            return "VISA"
        } else if self.isMatch(MasterCard_Regex) {
            return "MasterCard"
        } else if self.isMatch(AmericanExpress_Regex) {
            return "AmericanExpress"
        } else if self.isMatch(DinersClub_Regex) {
            return "DinersClub"
        } else if self.isMatch(Discover_Regex) {
            return "Discover"
        } else if self.isMatch(JCB_Regex) {
            return "JCB"
        } else {
            return nil
        }
        
    }
    
}

使用。

"1234123412341234".getCreditCardType()

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

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。

试试kotlin。添加Regex并添加到when语句中。

private fun getCardType(number: String): String {

        val visa = Regex("^4[0-9]{12}(?:[0-9]{3})?$")
        val mastercard = Regex("^5[1-5][0-9]{14}$")
        val amx = Regex("^3[47][0-9]{13}$")

        return when {
            visa.matches(number) -> "Visa"
            mastercard.matches(number) -> "Mastercard"
            amx.matches(number) -> "American Express"
            else -> "Unknown"
        }
    }

在swift中，您可以创建一个枚举来检测信用卡类型。

enum CreditCardType: Int { // Enum which encapsulates different card types and method to find the type of card.

case Visa
case Master
case Amex
case Discover

func validationRegex() -> String {
    var regex = ""
    switch self {
    case .Visa:
        regex = "^4[0-9]{6,}$"

    case .Master:
        regex = "^5[1-5][0-9]{5,}$"

    case .Amex:
        regex = "^3[47][0-9]{13}$"

    case .Discover:
        regex = "^6(?:011|5[0-9]{2})[0-9]{12}$"
    }

    return regex
}

func validate(cardNumber: String) -> Bool {
    let predicate = NSPredicate(format: "SELF MATCHES %@", validationRegex())
    return predicate.evaluateWithObject(cardNumber)
}

// Method returns the credit card type for given card number
static func cardTypeForCreditCardNumber(cardNumber: String) -> CreditCardType?  {
    var creditCardType: CreditCardType?

    var index = 0
    while let cardType = CreditCardType(rawValue: index) {
        if cardType.validate(cardNumber) {
            creditCardType = cardType
            break
        } else {
            index++
        }
    }
    return creditCardType
  }
}

调用方法CreditCardType。cardTypeForCreditCardNumber(“#卡号”)返回CreditCardType enum值。