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;
            }
        }
    };

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"
        }
    }

看看这个:

http://www.breakingpar.com/bkp/home.nsf/0/87256B280015193F87256CC70060A01B

function isValidCreditCard(type, ccnum) {
    /* Visa: length 16, prefix 4, dashes optional.
    Mastercard: length 16, prefix 51-55, dashes optional.
    Discover: length 16, prefix 6011, dashes optional.
    American Express: length 15, prefix 34 or 37.
    Diners: length 14, prefix 30, 36, or 38. */

    var re = new Regex({
        "visa": "/^4\d{3}-?\d{4}-?\d{4}-?\d",
        "mc": "/^5[1-5]\d{2}-?\d{4}-?\d{4}-?\d{4}$/",
        "disc": "/^6011-?\d{4}-?\d{4}-?\d{4}$/",
        "amex": "/^3[47]\d{13}$/",
        "diners": "/^3[068]\d{12}$/"
    }[type.toLowerCase()])

    if (!re.test(ccnum)) return false;
    // Remove all dashes for the checksum checks to eliminate negative numbers
    ccnum = ccnum.split("-").join("");
    // Checksum ("Mod 10")
    // Add even digits in even length strings or odd digits in odd length strings.
    var checksum = 0;
    for (var i = (2 - (ccnum.length % 2)); i <= ccnum.length; i += 2) {
        checksum += parseInt(ccnum.charAt(i - 1));
    }
    // Analyze odd digits in even length strings or even digits in odd length strings.
    for (var i = (ccnum.length % 2) + 1; i < ccnum.length; i += 2) {
        var digit = parseInt(ccnum.charAt(i - 1)) * 2;
        if (digit < 10) { checksum += digit; } else { checksum += (digit - 9); }
    }
    if ((checksum % 10) == 0) return true;
    else return false;
}

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

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。

一个javascript改进的@Anatoliy答案

function getCardType (number) { const numberFormated = number.replace(/\D/g, '') var patterns = { VISA: /^4[0-9]{12}(?:[0-9]{3})?$/, MASTER: /^5[1-5][0-9]{14}$/, AMEX: /^3[47][0-9]{13}$/, ELO: /^((((636368)|(438935)|(504175)|(451416)|(636297))\d{0,10})|((5067)|(4576)|(4011))\d{0,12})$/, AURA: /^(5078\d{2})(\d{2})(\d{11})$/, JCB: /^(?:2131|1800|35\d{3})\d{11}$/, DINERS: /^3(?:0[0-5]|[68][0-9])[0-9]{11}$/, DISCOVERY: /^6(?:011|5[0-9]{2})[0-9]{12}$/, HIPERCARD: /^(606282\d{10}(\d{3})?)|(3841\d{15})$/, ELECTRON: /^(4026|417500|4405|4508|4844|4913|4917)\d+$/, MAESTRO: /^(5018|5020|5038|5612|5893|6304|6759|6761|6762|6763|0604|6390)\d+$/, DANKORT: /^(5019)\d+$/, INTERPAYMENT: /^(636)\d+$/, UNIONPAY: /^(62|88)\d+$/, } for (var key in patterns) { if (patterns[key].test(numberFormated)) { return key } } } console.log(getCardType("4539 5684 7526 2091"))