A group of radio buttons is identified by the common name attribute. Out of a group of buttons, only one can be selected (or none). When submitting a form to the server, the value attribute of the selected radio buttons is transmitted to the server. Therefore, it is quite messy but rather trivial to prefill a group of radio buttons: Just compare the value in $_GET/$_POST with the associated value. If it fits, print out checked, the HTML attribute that preselects a radio button, as shown in the code. Prefilling Radio Buttons (radio.php; excerpt)<input type="radio" name="groupname" value="php3" <?php if (isset($_POST['groupname']) && $_POST ['groupname'] == 'php3') { echo 'checked="checked" '; } ?>/>PHP 3 <input type="radio" name="groupname" value="php4" <?php if (isset($_POST['groupname']) && $_POST['groupname'] == 'php4') { echo 'checked="checked" '; } ?>/>PHP 4 <input type="radio" name="groupname" value="php5" <?php if (isset($_POST['groupname']) && $_POST['groupname'] == 'php5') { echo 'checked="checked" '; } ?>/>PHP 5 This code can be extended so that a radio button is preselected when the user has previously saved his selection in a cookie, using the include file getFormData.inc.php, as shown in the following code. Prefilling Radio Buttons (radio-cookie.php; excerpt)<?php require_once 'getFormData.inc.php'; ?> ... <input type="radio" name="groupname" value="php3" <?php if (getFormDataPOST('groupname') == 'php3') { echo 'checked="checked" '; } ?>/>PHP 3 <input type="radio" name="groupname" value="php4" <?php if (getFormDataPOST('groupname') == 'php4') { echo 'checked="checked" '; } ?>/>PHP 4 <input type="radio" name="groupname" value="php5" <?php if (getFormDataPOST('groupname') == 'php5') { echo 'checked="checked" '; } ?>/>PHP 5 |