ISBNRule

public class ISBNRule: Rule

ISBNRule is a subclass of Rule. It is used to verify whether a field is a valid ISBN number.

  • Initializes a ISBNRule object to verify that field has text that is a ISBN number.

    Declaration

    Swift

    public init(message: String = "Enter valid ISBN number")

    Parameters

    message

    String of error message.

    Return Value

    An initialized object, or nil if an object could not be created for some reason that would not result in an exception.

  • Method used to validate text field.

    Declaration

    Swift

    public func validate(value: String) -> Bool

    Parameters

    value

    String to checked for validation.

    Return Value

    Boolean value. True if validation is successful; False if validation fails.

  • Method used to dispaly error message when text field fails validation.

    Declaration

    Swift

    public func errorMessage() -> String

    Return Value

    String of error message.