BUTTONS: radio

Select ONE of the following options

RADIOBUTTONS use a similar notation to CHECKBOXES, however only one option may be chosen among many.

Options:

VALUE="" REQUIRED

Specifies the value of the option to be sent to the server.

If not defined, a value of "on" is sent to the server.

CHECKED RECOMMENDED

This tag specifies which radiobutton to be selected by default.

Since it is implied that a selection will be made, it is best to provide a default selection.



<FORM METHOD="POST" ACTION="/cgi-bin/post-query">

Compile program with:
<DL>
<DD>Version
<INPUT TYPE="radio" NAME="version" VALUE="4.035">4.035
<INPUT TYPE="radio" NAME="version" VALUE="4.036">4.036
<INPUT TYPE="radio" NAME="version" VALUE="5.0" CHECKED>5.0
<DD>Output to: 
<INPUT TYPE="radio" NAME="output" VALUE="screen">screen
<INPUT TYPE="radio" NAME="output" VALUE="printer">printer
</DL>

</FORM>

Notes:

As mentioned before, RADIOBUTTONS are not good for lists with many items, because the browser has trouble displaying a lot of buttons. It would be best to use a SELECT menu element.
Once a radiobutton is selected, it cannot be deselected without choosing a radiobutton with the same NAME. The default selection can be restored with the use of the RESET button, which will be introduced in the next example.
If you have a bunch of RADIOBUTTONS with the same NAME and no VALUES specified, the server won't be able to tell which is selected, since a default value of "on" will be sent.

Carlos A. Pero

(c-pero@uiuc.edu)