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。

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。

在卡牌范围识别(CRR)中，使用一系列正则表达式或其他硬编码范围的算法的一个缺点是，根据我的经验，bin / iin会随着时间的推移而变化。信用卡的联合品牌是一个持续的复杂问题。不同的购卡商/商家可能会要求你不同地对待同一张卡，这取决于例如地理位置。

Additionally, in the last few years with e.g. UnionPay cards in wider circulation, existing models do not cope with new ranges that sometimes interleave with broader ranges that they supersede. Knowing the geography your system needs to cover may help, as some ranges are restricted to use in particular countries. For example, ranges 62 include some AAA sub-ranges in the US, but if your merchant base is outside the US, you may be able to treat all 62 as UnionPay. You may be also asked to treat a card differently based on merchant location. E.g. to treat certain UK cards as debit domestically, but as credit internationally.

There are very useful set of rules maintained by one major Acquiring Bank. E.g. https://www.barclaycard.co.uk/business/files/BIN-Rules-EIRE.pdf and https://www.barclaycard.co.uk/business/files/BIN-Rules-UK.pdf. (Valid links as of June 2017, thanks to the user who provided a link to updated reference.) But be aware of the caveat that, while these CRR rules may represent the Card Issuing universe as it applies to the merchants acquired by that entity, it does not include e.g. ranges identified as CUP/UPI.

这些注释适用于磁条(MagStripe)或PKE (Pan Key Entry)场景。在ICC/EMV领域，情况又有所不同。

更新:本页上的其他答案(以及链接的维基百科页面)的JCB始终是16长。然而，在我的公司，我们有一个专门的工程师团队，他们在多个银行和地区认证我们的POS设备和软件。这个团队从JCB获得的最新认证卡包，有一个19长PAN的合格案例。

更新日期:2016年6月15日(目前为最终解决方案)

请注意，我甚至放弃投票给一个被投票最多的，但为了明确这些是regexp实际上是有效的，我用数千个真实的BIN代码测试了它。最重要的是使用开始字符串(^)，否则在现实世界中会给出错误的结果!

JCB ^(?:2131|1800|35)[0-9]{0，}$开始:2131,1800,35 (3528-3589)

美国运通^3[47][0-9]{0，}$以:34,37开头

大莱卡^ 3(?:0(0-59){1}|[689])[0 - 9]{0}$开头:300 - 305年,309年,36岁,38-39

Visa ^4[0-9]{0，}$以:4开头

万事达卡^(5[1 - 5]| 222(1 - 9)| 22(3 - 9)| 2(3 - 6)| 27[01]| 2720)[0 - 9]{0}$开头:2221 - 2720,51-55

Maestro ^(5[06789]|6)[0-9]{0，}$ Maestro总是在范围内增长:60-69，以/开始，但开始5必须编码为万事达卡。大师卡必须在代码的末尾被检测到，因为其他一些卡的范围在60-69之间。请看代码。

发现^(6011|65|64[4-9]|62212[6-9]|6221[3-9]|622[2-8]|6229[01]|62292[0-5])[0-9]{0，}$发现很难编码，从:6011,622126 - 622925,644 -649,65开始

在javascript中，我使用这个函数。当你把它分配给一个onkeyup事件并尽快给出结果时，这是很好的。

function cc_brand_id(cur_val) {
    // the regular expressions check for possible matches as you type, hence the OR operators based on the number of chars
    // regexp string length {0} provided for soonest detection of beginning of the card numbers this way it could be used for BIN CODE detection also

    //JCB
    jcb_regex = new RegExp('^(?:2131|1800|35)[0-9]{0,}$'); //2131, 1800, 35 (3528-3589)
    // American Express
    amex_regex = new RegExp('^3[47][0-9]{0,}$'); //34, 37
    // Diners Club
    diners_regex = new RegExp('^3(?:0[0-59]{1}|[689])[0-9]{0,}$'); //300-305, 309, 36, 38-39
    // Visa
    visa_regex = new RegExp('^4[0-9]{0,}$'); //4
    // MasterCard
    mastercard_regex = new RegExp('^(5[1-5]|222[1-9]|22[3-9]|2[3-6]|27[01]|2720)[0-9]{0,}$'); //2221-2720, 51-55
    maestro_regex = new RegExp('^(5[06789]|6)[0-9]{0,}$'); //always growing in the range: 60-69, started with / not something else, but starting 5 must be encoded as mastercard anyway
    //Discover
    discover_regex = new RegExp('^(6011|65|64[4-9]|62212[6-9]|6221[3-9]|622[2-8]|6229[01]|62292[0-5])[0-9]{0,}$');
    ////6011, 622126-622925, 644-649, 65


    // get rid of anything but numbers
    cur_val = cur_val.replace(/\D/g, '');

    // checks per each, as their could be multiple hits
    //fix: ordering matter in detection, otherwise can give false results in rare cases
    var sel_brand = "unknown";
    if (cur_val.match(jcb_regex)) {
        sel_brand = "jcb";
    } else if (cur_val.match(amex_regex)) {
        sel_brand = "amex";
    } else if (cur_val.match(diners_regex)) {
        sel_brand = "diners_club";
    } else if (cur_val.match(visa_regex)) {
        sel_brand = "visa";
    } else if (cur_val.match(mastercard_regex)) {
        sel_brand = "mastercard";
    } else if (cur_val.match(discover_regex)) {
        sel_brand = "discover";
    } else if (cur_val.match(maestro_regex)) {
        if (cur_val[0] == '5') { //started 5 must be mastercard
            sel_brand = "mastercard";
        } else {
            sel_brand = "maestro"; //maestro is all 60-69 which is not something else, thats why this condition in the end
        }
    }

    return sel_brand;
}

在这里你可以玩它:

http://jsfiddle.net/upN3L/69/

对于PHP使用这个函数，它也会检测一些子VISA/MC卡:

/**
  * Obtain a brand constant from a PAN
  *
  * @param string $pan               Credit card number
  * @param bool   $include_sub_types Include detection of sub visa brands
  * @return string
  */
public static function getCardBrand($pan, $include_sub_types = false)
{
    //maximum length is not fixed now, there are growing number of CCs has more numbers in length, limiting can give false negatives atm

    //these regexps accept not whole cc numbers too
    //visa
    $visa_regex = "/^4[0-9]{0,}$/";
    $vpreca_regex = "/^428485[0-9]{0,}$/";
    $postepay_regex = "/^(402360|402361|403035|417631|529948){0,}$/";
    $cartasi_regex = "/^(432917|432930|453998)[0-9]{0,}$/";
    $entropay_regex = "/^(406742|410162|431380|459061|533844|522093)[0-9]{0,}$/";
    $o2money_regex = "/^(422793|475743)[0-9]{0,}$/";

    // MasterCard
    $mastercard_regex = "/^(5[1-5]|222[1-9]|22[3-9]|2[3-6]|27[01]|2720)[0-9]{0,}$/";
    $maestro_regex = "/^(5[06789]|6)[0-9]{0,}$/";
    $kukuruza_regex = "/^525477[0-9]{0,}$/";
    $yunacard_regex = "/^541275[0-9]{0,}$/";

    // American Express
    $amex_regex = "/^3[47][0-9]{0,}$/";

    // Diners Club
    $diners_regex = "/^3(?:0[0-59]{1}|[689])[0-9]{0,}$/";

    //Discover
    $discover_regex = "/^(6011|65|64[4-9]|62212[6-9]|6221[3-9]|622[2-8]|6229[01]|62292[0-5])[0-9]{0,}$/";

    //JCB
    $jcb_regex = "/^(?:2131|1800|35)[0-9]{0,}$/";

    //ordering matter in detection, otherwise can give false results in rare cases
    if (preg_match($jcb_regex, $pan)) {
        return "jcb";
    }

    if (preg_match($amex_regex, $pan)) {
        return "amex";
    }

    if (preg_match($diners_regex, $pan)) {
        return "diners_club";
    }

    //sub visa/mastercard cards
    if ($include_sub_types) {
        if (preg_match($vpreca_regex, $pan)) {
            return "v-preca";
        }
        if (preg_match($postepay_regex, $pan)) {
            return "postepay";
        }
        if (preg_match($cartasi_regex, $pan)) {
            return "cartasi";
        }
        if (preg_match($entropay_regex, $pan)) {
            return "entropay";
        }
        if (preg_match($o2money_regex, $pan)) {
            return "o2money";
        }
        if (preg_match($kukuruza_regex, $pan)) {
            return "kukuruza";
        }
        if (preg_match($yunacard_regex, $pan)) {
            return "yunacard";
        }
    }

    if (preg_match($visa_regex, $pan)) {
        return "visa";
    }

    if (preg_match($mastercard_regex, $pan)) {
        return "mastercard";
    }

    if (preg_match($discover_regex, $pan)) {
        return "discover";
    }

    if (preg_match($maestro_regex, $pan)) {
        if ($pan[0] == '5') { //started 5 must be mastercard
            return "mastercard";
        }
        return "maestro"; //maestro is all 60-69 which is not something else, thats why this condition in the end

    }

    return "unknown"; //unknown for this system
}

我用jQuery的解决方案:

function detectCreditCardType() {
    var type = new Array;
    type[1] = '^4[0-9]{12}(?:[0-9]{3})?$';      // visa
    type[2] = '^5[1-5][0-9]{14}$';              // mastercard
    type[3] = '^6(?:011|5[0-9]{2})[0-9]{12}$';  // discover
    type[4] = '^3[47][0-9]{13}$';               // amex

    var ccnum = $('.creditcard').val().replace(/[^\d.]/g, '');
    var returntype = 0;

    $.each(type, function(idx, re) {
        var regex = new RegExp(re);
        if(regex.test(ccnum) && idx>0) {
            returntype = idx;
        }
    });

    return returntype;
}

如果返回0，则未检测到信用卡类型。

“creditcard”类应该添加到creditcard输入字段中。

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 ""

}