If you need something like this in a pre 4.3 version, here is a rough hack I was working on before I realized I didn't need this after all.

preg_match('/Fields\[(.*)\]/', $raw_pdf, $field_data);
echo "Fields: ", htmlentities($field_data[1]), "<HR>\n";
$field_data = $field_data[1];
$key_value = explode(">><<", $field_data);
$key_value[0] = substr($key_value[0], 2);
$key_value[count($key_value) - 1] = substr($key_value[count($key_value) - 1], 0, -2);
while (list(, $kv) = each($key_value)){
list($key, $value) = explode("/V", $kv);
$key = substr($key, 2);
if ($key[0] == '('){
$key = substr($key, 1, -1);
}
if ($value[0] == '/'){
$value = substr($value, 1);
}
if ($value[0] == '('){
$value = substr($value, 1, -1);
}
echo "Key: $key Value: $value<BR>\n";
}

The $raw_pdf can either be the $HTTP_RAW_POST_DATA before you write a submitted PDF, or it can just be the raw PDF data you would read from a PDF using, say:
$raw_pdf = implode("", file("/path/to/your/fdf/whatever.pdf"));

You'll probably need to tweak this to do something more interesting than just printing the stuff.

Hmmmm. Think they'll throw me in jail for this post? Oh well.
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Manual Page -- [url]http://www.php.net/manual/en/function.fdf-enum-values.php[/url]
Edit Note -- [url]http://master.php.net/manage/user-notes.php?action=edit+33904[/url]
Delete Note -- [url]http://master.php.net/manage/user-notes.php?action=delete+33904&report=yes[/url]
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