Why does $_REQUEST work but not $_POST

I’m building an OOP plugin to create admin pages to be used by a Multisite superadmin that uses a custom table. It’s a simple routine. Pick a record from a dropdown list, then get all the field data and display a second form to edit those fields.

Since there seems to be no way to call a class method in the action = part of the form tag, I’ve written a function that uses action = ” so the page will call itself on submit. The method is POST

Here’s the logic:

if($_POST['form_two'] !== 'save_data' ){
   global $wpdb ;
   //do a query, get some values create a form to
   // let the user select one from a dropdown
   echo '<form type="post" action="" id="select_one" name "select_one">';
   // a foreach to populate and display the <select> element
   echo '<input type="hidden" name="form_two" id="form_two" value="save_data"/>';
   echo '<input name="send_select" id="send_select" type="submit" value="Select Ad To Edit" />';
   echo '</form>';
} else {
// the code for the edit form
}

Fails every time. But change _POST to $_REQUEST and it works perfectly. You get an ungainly URL when you use REQUEST, which seems a bit odd too, but it works great.

I just want to know why $_POST doesn’t get populated but $_REQUEST does. It took me a LONG LONG time to figure out this hack. I’ just like to gain a little knowlege for the effort.

Thanks,

Ed