HTML and CSS Reference
In-Depth Information
VALIDATION: STOPPING
ERRORS
The fields in a form are there to gather information from
web page visitors. But no matter how politely you ask,
you might not get what you want. Impatient or confused
visitors can skip over important sections, enter partial
information, or just hit the wrong keys. The end result?
They click Submit, and your website gets a whackload of
scrambled data.
What a respectable web page needs is
validation
—a way
to catch mistakes when they happen (or even better, to
prevent them from happening at all). For years, deve-
lopers have done that by writing their own JavaScript
routines or using professional JavaScript libraries. And,
