 | Tool for displaying and managing data. |
| Used for both client and server applications. |
| Form tag (<form>) contains one or more elements making up the form.
Multiple forms can exist in a document. |
| Key attributes for the form tag:
 | action - file name, URL, or script to be run |
| method - POST (sends form data to server via data stream) or
GET (appends data to URL: www.acme.com/cgi-bin/progname?productid=123456).
GET is best for small forms, POST for larger forms and to hide data.
GET is also useful for dynamically constructed URLs with information. |
| name - object name for the form |
| enctype - encoding instructions for the form data
(default is "application/x-www-form-urlencoded" - sets spaces
to + and nonalpha characters to %, line breaks to %0D%0A). |
|
| mailto: is a popular way to submit form information via a browser/mail
function (does not work if mail is not set up in a browser). |
| Form input elements:
| button - interactive button (major use is in client applications)
|
| submit - used to send form data to the action designation. |
| reset - restores form to original state (not necessarily a clear
function). |
| checkbox - binary selection |
| file - send files to the browser (user must select file) |
| hidden - good for hiding data |
| image - can be used as a submit object |
| password - variation of a text box, hides content |
| radio - group buttons (all buttons with the same name work
together) |
| text - single line text entry box |
| select - drop-down and list, use option items for each entry
(size="1" causes single line drop down box; size > 1 creates list box). |
| textarea - multiline text box |
|
| User issues:
| Make forms explanation intensive, never assume anything about how data
is entered. |
| Tables are a great way to structure a forms appearance. |
| Make form/input element names meaningful (will help you with
client/server apps). |
|
CGI = Common Gateway Interface - the protocol that defines how servers
interact with other programs on the server. Key functions include:
| Ability to get information submitted via a browser form (i.e., the program
can get data submitted via the form, e.g., fields). |
| Ability to transmit HTML output. |
| Ability to access server specific data (e.g., name of server, URL specific
information). |
| Ability to track information between sessions (i.e., pages served). |
| Ability to call/run/terminate (politely) applications. |
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