不要试图检测信用卡类型作为处理支付的一部分。您正在冒着拒绝有效事务的风险。

如果您需要向您的支付处理器提供信息(例如，PayPal信用卡对象需要命名卡类型)，那么从可用的最少信息中猜测它，例如。

$credit_card['pan'] = preg_replace('/[^0-9]/', '', $credit_card['pan']);
$inn = (int) mb_substr($credit_card['pan'], 0, 2);

// @see http://en.wikipedia.org/wiki/List_of_Bank_Identification_Numbers#Overview
if ($inn >= 40 && $inn <= 49) {
    $type = 'visa';
} else if ($inn >= 51 && $inn <= 55) {
    $type = 'mastercard';
} else if ($inn >= 60 && $inn <= 65) {
    $type = 'discover';
} else if ($inn >= 34 && $inn <= 37) {
    $type = 'amex';
} else {
    throw new \UnexpectedValueException('Unsupported card type.');
}

这个实现(只使用前两位数字)足以识别所有主要的(在PayPal的情况下是所有受支持的)卡片方案。实际上，您可能希望完全跳过异常，并默认使用最流行的卡片类型。让支付网关/处理器告诉您在响应您的请求时是否存在验证错误。

现实情况是，你的支付网关并不关心你提供的价值。

最近我需要这样的功能，我将Zend框架信用卡验证器移植到ruby。 红宝石宝石:https://github.com/Fivell/credit_card_validations zend框架:https://github.com/zendframework/zf2/blob/master/library/Zend/Validator/CreditCard.php

它们都使用INN范围来检测类型。在这里你可以读到关于INN的信息

根据这一点，您可以选择检测信用卡(没有regexp，但声明一些关于前缀和可能长度的规则)

所以我们有关于最常用卡片的下一个规则

########  most used brands #########

    visa: [
        {length: [13, 16], prefixes: ['4']}
    ],
    mastercard: [
        {length: [16], prefixes: ['51', '52', '53', '54', '55']}
    ],

    amex: [
        {length: [15], prefixes: ['34', '37']}
    ],
    ######## other brands ########
    diners: [
        {length: [14], prefixes: ['300', '301', '302', '303', '304', '305', '36', '38']},
    ],

    #There are Diners Club (North America) cards that begin with 5. These are a joint venture between Diners Club and MasterCard, and are processed like a MasterCard
    # will be removed in next major version

    diners_us: [
        {length: [16], prefixes: ['54', '55']}
    ],

    discover: [
        {length: [16], prefixes: ['6011', '644', '645', '646', '647', '648',
                                  '649', '65']}
    ],

    jcb: [
        {length: [16], prefixes: ['3528', '3529', '353', '354', '355', '356', '357', '358', '1800', '2131']}
    ],


    laser: [
        {length: [16, 17, 18, 19], prefixes: ['6304', '6706', '6771']}
    ],

    solo: [
        {length: [16, 18, 19], prefixes: ['6334', '6767']}
    ],

    switch: [
        {length: [16, 18, 19], prefixes: ['633110', '633312', '633304', '633303', '633301', '633300']}

    ],

    maestro: [
        {length: [12, 13, 14, 15, 16, 17, 18, 19], prefixes: ['5010', '5011', '5012', '5013', '5014', '5015', '5016', '5017', '5018',
                                                              '502', '503', '504', '505', '506', '507', '508',
                                                              '6012', '6013', '6014', '6015', '6016', '6017', '6018', '6019',
                                                              '602', '603', '604', '605', '6060',
                                                              '677', '675', '674', '673', '672', '671', '670',
                                                              '6760', '6761', '6762', '6763', '6764', '6765', '6766', '6768', '6769']}
    ],

    # Luhn validation are skipped for union pay cards because they have unknown generation algoritm
    unionpay: [
        {length: [16, 17, 18, 19], prefixes: ['622', '624', '625', '626', '628'], skip_luhn: true}
    ],

    dankrot: [
        {length: [16], prefixes: ['5019']}
    ],

    rupay: [
        {length: [16], prefixes: ['6061', '6062', '6063', '6064', '6065', '6066', '6067', '6068', '6069', '607', '608'], skip_luhn: true}
    ]

}

然后通过搜索前缀和比较长度来检测信用卡品牌。也不要忘记luhn算法(在http://en.wikipedia.org/wiki/Luhn有描述)。

更新

更新的规则列表可以在这里找到https://raw.githubusercontent.com/Fivell/credit_card_validations/master/lib/data/brands.yaml

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

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 ""

}

只需一点点的勺子喂养:

$("#CreditCardNumber").focusout(function () {


        var regVisa = /^4[0-9]{12}(?:[0-9]{3})?$/;
        var regMasterCard = /^5[1-5][0-9]{14}$/;
        var regAmex = /^3[47][0-9]{13}$/;
        var regDiscover = /^6(?:011|5[0-9]{2})[0-9]{12}$/;

        if (regVisa.test($(this).val())) {
            $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/visa.png")'>");          

        }

        else if (regMasterCard.test($(this).val())) {
        $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/mastercard.png")'>");

        }

        else if (regAmex.test($(this).val())) {

           $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/amex.png")'>");

        }
         else if (regDiscover.test($(this).val())) {

           $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/discover.png")'>");

        }
        else {
        $("#CCImage").html("NA");

        }

    });

压缩javascript版本

    var getCardType = function (number) {
        var cards = {
            visa: /^4[0-9]{12}(?:[0-9]{3})?$/,
            mastercard: /^5[1-5][0-9]{14}$/,
            amex: /^3[47][0-9]{13}$/,
            diners: /^3(?:0[0-5]|[68][0-9])[0-9]{11}$/,
            discover: /^6(?:011|5[0-9]{2})[0-9]{12}$/,
            jcb: /^(?:2131|1800|35\d{3})\d{11}$/
        };
        for (var card in cards) {
            if (cards[card].test(number)) {
                return card;
            }
        }
    };