Chapter 15. Using JavaScript with web forms

After completing this chapter, you will be able to

  • Understand how to validate the input to a web form using JavaScript.

  • Work with radio buttons, select boxes, and check boxes, both to get their values and to set their state.

  • Provide feedback based on validation, both through an alert() dialog box and inline within the document.

  • Understand the limitations of JavaScript form validation, and see an example of validation gone wrong.

JavaScript and web forms

JavaScript has been used with web forms for a long time—typically, to quickly verify that a user has filled in form fields correctly before sending that form to the server, a process called client-side validation. Prior to JavaScript, a browser had to send ...

Get JavaScript Step by Step now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.