How do I sort multiples pages?

Question

I want to use a dropdown to sort a list of posts in WordPress. The results will display on multiple pages. So how do I pass the query on to the second, third, fourth, etc. pages?

Here's an example of my form.

<form method="post" id="order">
  <select name="sort" onchange='this.form.submit()'>
    <option value="">Sort by</option>  
    <option value="zip">Sort by Zip Code</option>
    <option value="type">Sort by Property Type</option>
  </select>
</form>

Thank you,

John

Answer 1

Use sessions:

<?php
session_start();

if( isset( $_POST['order'] ){
  $order = filter_input( INPUT_POST, 'order', FILTER_SANITIZE_STRING );

   if( $order )
    $_SESSION['order'] = $order;

}

if( isset( $_SESSION['order'] )
  $order = $_SESSION['order'];