Files
go-utils/bank_card/validator.go
2023-10-17 23:06:53 +08:00

55 lines
1.1 KiB
Go

package bank_card
// IsValidLuhn 使用Luhn算法校验银行卡号码
// @see https://en.wikipedia.org/wiki/Luhn_algorithm
// @see https://www.geeksforgeeks.org/luhn-algorithm/
// @see https://medium.com/@akshaymohite/luhns-algorithm-to-validate-credit-debit-card-numbers-1952e6c7a9d0
// @see https://www.woshipm.com/pd/371041.html
func IsValidLuhn(cardNo string) bool {
length := len(cardNo)
if length == 0 {
return false
}
if !isNumberString(cardNo) {
return false
}
sum := 0
second := false
for i := length - 1; i >= 0; i-- {
d := cardNo[i] - '0'
if second == true {
d = d * 2
}
sum += int(d) / 10
sum += int(d) % 10
second = !second
}
return sum%10 == 0
}
// IsValidBankCardNo 是否合法的银行卡号
func IsValidBankCardNo(cardNo string) bool {
length := len(cardNo)
if length < 12 || length > 19 {
return false
}
return IsValidLuhn(cardNo)
}
// isNumberString 验证字符是数字
func isNumberString(s string) bool {
length := len(s)
for i := 0; i < length; i++ {
if s[i] < '0' || s[i] > '9' {
return false
}
}
return true
}