A PHP function to get an array of field names and default values from an HTML form on a remote server.

formgetcontents.php

<?php

/**
 * Contains a function to get the contents of a live form.
 *
 * PHP Version 5.3
 *
 * Requires the allow_url_fopen parameter to be set to true in php.ini.
 *
 * @category FormProcessing
 * @package  HTMLFormProcessing
 * @author   Kevin Fodness <kevin@kevinfodness.com>
 * @license  http://www.gnu.org/licenses/gpl.html GNU Public License v3
 * @link     http://www.kevinfodness.com
 */

/**
 * A function to get the contents of a live form.
 *
 * @param string $formId  The ID attribute of the form to match.
 * @param string $formUrl The URL where the form can be found.
 *
 * @return array An associative array of form fields and default values.
 */
function formGetContents($formId, $formUrl)
{
    /** Get the form as a DOMElement. */
    $page = new DOMDocument();
    $page->loadHTML(file_get_contents($formUrl));
    $form = $page->getElementById($formId);

    /** Initialize the content array, which contains return data. */
    $content = array();

    /** Get the INPUT tags. */
    $inputNodes = $form->getElementsByTagName('input');
    foreach ($inputNodes as $node) {
        $name  = $node->getAttribute('name');
        $value = $node->getAttribute('value');
        if (strlen($name) > 0) {
            $content[$name] = $value;
        }
    }
    unset($inputNodes);

    /** Get the SELECT tags. */
    $selectNodes = $form->getElementsByTagName('select');
    foreach ($selectNodes as $node) {
        $name    = $node->getAttribute('name');
        $options = $node->getElementsByTagName('option');
        $length  = $options->length;
        $value   = $options->item(0)->getAttribute('value');
        for ($i = 0; $i < $length; $i++) {
            if ($options->item($i)->getAttribute('selected')) {
                $value = $options->item($i)->getAttribute('value');
            }
        }
        if (strlen($name) > 0) {
            $content[$name] = $value;
        }
    }
    unset($selectNodes);

    /** Get the TEXTAREA tags. */
    $textareaNodes = $form->getElementsByTagName('textarea');
    foreach ($textareaNodes as $node) {
        $name  = $node->getAttribute('name');
        $value = preg_replace(
            '/<textarea.*?>(.*)<\/textarea>/i',
            '$1',
            $node->ownerDocument->saveXML($node)
        );
        if (strlen($name) > 0) {
            $content[$name] = $value;
        }
    }
    unset($textareaNodes);

    return $content;
}

?>