Dreamweaver CS5: The Missing Manual

Validating Forms

You might get frustrated when you review feedback submitted via a form on your web page, only to notice that your visitor failed to provide a name, email address, or some other critical piece of information. That’s why, depending on the type of form you create, you might want to make certain information mandatory.

For instance, a form used for subscribing to an email newsletter isn’t much use if the would-be reader doesn’t type in an email address. Likewise, if you need a shipping address to deliver a brochure or product, you want to be sure that the visitor includes his address on the form.

Luckily, Dreamweaver includes a set of validation options that do exactly this: Spry Validation “widgets.” (The term widget refers to any of the Spry-based, interactive web page element that Dreamweaver helps you create, such as the Spry Menu Bar, Spry Validation Text Field, and Spry Tabbed Panels.) With a Spry Validation widget, you can display a friendly “Hey, please fill out this box” message when someone tries to submit a form that’s missing important information. You can specify that visitors can’t leave a particular field blank, or that a field must contain information in a specific format, such as a phone number, email address, or credit card number. If someone tries to submit a form without the correct information, your message appears. And instead of an annoying and amateurish JavaScript error window popping up, Spry form validation widgets display error messages right ...