ISBN13 Validation

• Download ISBN samples - 25.7 KB
• Download ISBN code - 2.75 KB

Introduction

This is my first article and hopefully not the last. I was looking for a good and simple article to start with. I hope this is a good start and that you guys can use my code.

The function of this article is to explain the possibilities of the ISBN13 validation object I created. It validates a few different things specified by ISBN International. I will explain them in this article.

Background

The basic idea behind ISBN numbers is code standard for books. For those of you who want to know more about ISBN, here is some info from Wikipedia and ISBN International.

Related Articles

There is another article (ASP.NET ISBN Validator) on The Code Project about ISBN validation. However, there are a few differences.

This code:

• is written in C#
• has a separate ISBN13 validation class
• validates on grouped and ungroup ISBN13 numbers
• only validates ISBN13 numbers (this is the standard at the moment)

Using the Code

The code is very basic and straightforward. The library has a class ISBN.ISBN13. Here is an example code to show the use of the class. As you can see, the constructor has an overload to input the ISBN directly.

ISBN.ISBN13 isbnValid = new ISBN13();
isbnValid.ISBN = "978-0-571-08989-5";

ISBN.ISBN13 isbnValid2 = new ISBN13("978-0-571-08989-5");

Validation is done directly when the ISBN is set. You can see if it is valid with the IsValid property.

ISBN13 also has some static methods that are interesting. These are easy to use.

• C#

  IsValidISBN(string isbn) : bool 

• C#

  GetISBNFormat(string isbn) : ISBNGroupingFormat 

• C#

  ValidateChecksum(string isbn) : bool 

To use the validator control, add the ToolboxItem. This way you can drag and drop the control. It is inherited from the CustomValidator control. The validation is done by the ISBN13 class.

You can also add this to use the ISBN validator in your ASP form.

    <%@ register assembly="ISBN" namespace="ISBN.Web" tagprefix="cc1" %> 
    <%cc1:isbn13validator controltovalidate="TextBox1" 
    runat="server" id="ISBN13Validator1"%> 
</cc1:isbn13validator%>

Points of Interest

One of the most interesting points to look at is the wild RegEx string used to validate the grouped ISBN. Is my first RegEx this long?

History

• 27^th March, 2007: Initial post