ChecksumUtility

@objc public final class ChecksumUtility : NSObject

Utility for checksum generation and validation


                    
                    
                    crc16(string:)

Generate CRC16

Parameter

Parameter string: String to generate crc for

Returns

CRC16 in 4 digit hex code string format with 0 as padding

Declaration

Swift

public static func crc16(string: String) -> String

Parameters


                                string

String to generate crc for

Return Value

CRC16 in 4 digit hex code string format with 0 as padding


                    
                    
                    isValidCrc16(qrString:)

Checks if the qr string includes valid CRC16

Parameter

Parameter qrString: QR code string

Returns

true if the CRC16 in the qrString is valid else false

Declaration

Swift

public static func isValidCrc16(qrString: String) -> Bool

Parameters


                                qrString

QR code string

Return Value

true if the CRC16 in the qrString is valid else false

Luhn checksum


                    
                    
                    validateLuhnChecksum(_:)

Valid luhn checksum of the string

Parameter

Parameter string: String to valid luhn checksum for

Returns

true if luhn checksum of the string is valid

Precondition

string should be numeric otherwise this method returns false

Declaration

Swift

public static func validateLuhnChecksum(_ string: String) -> Bool

Parameters


                                string

String to valid luhn checksum for

Return Value

true if luhn checksum of the string is valid


                    
                    
                    luhnChecksum(_:)

Generate luhn checksum of the string.

Parameter

Parameter string: String to valid luhn checksum for

Returns

Integer luhn checksum

Throws

MPQRError.invalidFormat if the the string is not numeric

Precondition

Check digit should not be present in the string

Declaration

Swift

public static func luhnChecksum(_ string: String) throws -> NSNumber

Parameters


                                string

String to valid luhn checksum for

Return Value

Integer luhn checksum


                    
                    
                    luhnChecksum(_:hasCheckDigit:)

Generate luhn checksum of the string

Parameter

Parameter string: String to valid luhn checksum for

Parameter

Parameter hasCheckDigit: Whether Check digit is already present in the string or not.

Returns

Integer luhn checksum

Throws

MPQRError.invalidFormat if the the string is not numeric

Declaration

Swift

public static func luhnChecksum(_ string: String, hasCheckDigit: Bool) throws -> NSNumber

Parameters

`string`	String to valid luhn checksum for
`hasCheckDigit`	Whether `Check digit` is already present in the string or not.

Return Value

Integer luhn checksum