Peter Lubbers - Pro HTML 5 Programming

CHAPTER 7 ■ USING THE HTML5 FORMS API
and its virtual keyboard display, as we will see shortly. More advanced features such as validation are
just being introduced. Table 7-1 summarizes the current state of HTML5 Forms support today.
Table 7-1. Browser support for HTML5 Forms
Browser Details
Chrome 5.0.x supports input types email, number, tel, url, search, and range. Most
validation.
Firefox Not supported in 3.6. Initial support coming in 4.0.Unsupported input types such
as url, email, and range will fall back to a text field.
Internet Explorer Not supported, but new types will fall back to a text field rendering.
Opera Strong support for initial specifications in current versions, including validation.
Safari 4.0.x supports input types email, number, tel, url, search, and range. Most
validation. Some types supported better in mobile Safari.
Checking for browser support is less useful in the context of the new HTML5 Forms, as they have
been designed to degrade gracefully in older browsers. Largely, this means that it is safe for you to use
the new elements today, because older browsers will fall back to simple text field displays for any input
types that they do not understand. However, as we’ll see later in this chapter, this raises the importance
of multi-tier form validation, as it is not sufficient to rely on the presence of browser validators to enforce
the data types for your form controls, even if you assume full modern-browser support.
Now that we have surveyed the browser landscape, let’s take a look at the new form controls added
in the HTML5 specification.
An Input Catalog
One of the best places to get a catalog of all the new and changed elements in HTML5 is the markup list
maintained at the W3C site itself. The W3C keeps a catalog page file at http://dev.w3.org/html5/markup/
This page denotes all the current and future elements in an HTML page. New and changed elements
are noted in the catalog list. However, “new” in this list only means that the element has been added
since the HTML4 specification—not that the element is implemented in browsers or in a final
specification yet. With that warning in place, let’s take a look at the new form elements arriving with
HTML5, starting with the ones that are being implemented today. Table 7-2 lists the new type attributes.
For example, many HTML developers will be intimately familiar with and . The new input types follow a similar model to the existing ones.
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