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390

Chapter 16 Using HTML Forms

16.2 The FORM Element

HTML forms allow you to create a set of data input elements associated with

a particular URL. Each of these elements is typically given a name and has a

value based on the original HTML or user input. When the form is submit 

ted, the names and values of all active elements are collected into a string

with 

= 

between each name and value and with 

&

 between each name/value

pair. This string is then transmitted to the URL designated by the 

FORM

 ele 

ment. The string is either appended to the URL after a question mark or sent

on a separate line after the HTTP request headers and a blank line, depend 

ing on whether 

GET

 or 

POST

 is used as the submission method. This section

covers the 

FORM

 element itself, used primarily to designate the URL and to

choose the submission method. The following sections cover the various user

interface controls that can be used within forms.

HTML Element:

 ... 

Attributes:

ACTION

 (required), 

METHOD

, 

ENCTYPE

, 

TARGET

, 

ONSUBMIT

, 

ONRESET

, 

ACCEPT

, 

ACCEPT CHARSET

The 

FORM

 element creates an area for data input elements and designates the

URL to which any collected data will be transmitted. For example:

FORM input elements and regular HTML

The rest of this section explains the attributes that apply to the 

FORM

 ele 

ment: 

ACTION

, 

METHOD

, 

ENCTYPE

, 

TARGET

, 

ONSUBMIT

, 

ONRESET

, 

ACCEPT

, and

ACCEPT CHARSET

. Note that I am not discussing attributes like 

STYLE

, 

CLASS

,

and 

LANG

 that apply to general HTML elements, but only those that are spe 

cific to the 

FORM

 element. 

ACTION

The 

ACTION

 attribute specifies the URL of the servlet or CGI program 

that will process the 

FORM

 data (e.g., 

http://cgi.whitehouse.gov/ 

bin/schedule fund raiser

) or an email address where the 

FORM

data will be sent (e.g., 

mailto:audit@irs.gov

). Some ISPs do not 

allow ordinary users to create servlets or CGI programs, or they charge 

extra for this privilege. In such a case, sending the data by email is a 

convenient option when you create pages that need to collect data but 

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