Question

I’m trying to call out a form within a form where the second form action does not work. It didn’t parse. My sample program have one main form which is attached to my submit button and inner form would be a download button.

Updated code:

<?php
$fullPath = "staff.doc";
<form id="Staff" name="Staff" method="post" action="download_preview.php">
echo "<input type=\"hidden\" name=\"fullPath\" value=\"$fullPath\"/>";
echo "<input type=\"submit\" name=\"submit\" value=\"Download\"/>";
echo "<input type=\"submit\" id=\"Submit\" name=\"Submit\" value\="Submit\"/>";
echo "</form>";

<?php
switch($_POST['submit']) 
{
case "Submit":

break;
case "Download":
$fullPath = $_POST['fullPath'];
// download file

     opendir("$fullPath");

break;
default:
}
?>

I have updated with the multiple handler approach. But i’m still not able to call out the download path. The code for the download was working previously with a single form.

Answer 1

As stated in the XHTML spec,

form: must not contain other form elements.

And if it’s in the spec, you should not rely on how any given user-agent vendor handles it. And just in case you aren’t familiar with how the folks over there use phrases like "must not", there’s this:

Must:
In this specification, the word "must" is to be interpreted as a mandatory requirement on the implementation or on Strictly Conforming XHTML Documents, depending upon the context. The term "shall" has the same definition as "must".

EDIT: I was curious, and found that the HTML5 spec also includes language forbidding nested forms.

EDIT (code suggestions):

method one: the sibling-forms approach

<?php $fullPath = $_SERVER['DOCUMENT_ROOT']."/doc/store"."$T"; ?>
<form id="Staff" name="Staff" method="post" action="gotonextpage.php">
  <input type="submit" name="Submit" value='Submit'>
</form>
<form name="download" action="download.php" method="post">";
  <input type="hidden" name="fullPath" value="<?php echo $fullPath ?>"/>";
  <input type="submit" name="submit" value="Download"/>";
</form>

method two: the multi-purpose handler approach

<?php $fullPath = $_SERVER['DOCUMENT_ROOT']."/doc/store"."$T"; ?>
<form id="Staff" name="Staff" method="post" action="downlod_or_gotonextpage.php">
  <input type="submit" name="Submit" value='Submit'>
  <input type="hidden" name="fullPath" value="<?php echo $fullPath ?>"/>";
  <input type="submit" name="submit" value="Download"/>";
</form>

And then make downlod_or_gotonextpage.php

switch($_POST['submit']) {
  case "Submit":
    // go to next page, either with 302, include, or whatever is appropriate
    break;
  case "Download":
    // do downloading, perhaps also with a 302 first...
    break;
  default:
    // 404, or 302 to the original form page
}