title: using a base64 encoded string in url with codeigniter
body: <p>I have an encrypted, base64 encoded array that I need to put into a url and insert into emails we send to clients to enable them to be identified (uniquely) - the problem is that base64_encode() often appends an = symbol or two after it's string of characters, which by default is disallowed by CI.</p>
  
  <p>Here's an example:
  <a href="http://example.com/cec/pay_invoice/VXpkUmJnMWxYRFZWTEZSd0RXZFRaMVZnQWowR2N3TTdEVzRDZGdCbkQycFFaZ0JpQmd4V09RRmdWbkVMYXdZbUJ6OEdZQVJ1QlNJTU9Bb3RWenNFSmxaaFVXcFZaMXQxQXpWV1BRQThVVEpUT0ZFZ0RRbGNabFV6VkNFTlpsTWxWV29DTmdackEzQU5Nd0lpQURNUGNGQS9BRFlHWTFacUFTWldOZ3M5QmpRSGJBWTlCREVGWkF4V0NtQlhiZ1IzVm1CUk9sVm5XMllEWlZaaEFHeFJZMU51VVdNTmJsdzNWVzlVT0EwZw==" rel="noreferrer">http://example.com/cec/pay_invoice/VXpkUmJnMWxYRFZWTEZSd0RXZFRaMVZnQWowR2N3TTdEVzRDZGdCbkQycFFaZ0JpQmd4V09RRmdWbkVMYXdZbUJ6OEdZQVJ1QlNJTU9Bb3RWenNFSmxaaFVXcFZaMXQxQXpWV1BRQThVVEpUT0ZFZ0RRbGNabFV6VkNFTlpsTWxWV29DTmdackEzQU5Nd0lpQURNUGNGQS9BRFlHWTFacUFTWldOZ3M5QmpRSGJBWTlCREVGWkF4V0NtQlhiZ1IzVm1CUk9sVm5XMllEWlZaaEFHeFJZMU51VVdNTmJsdzNWVzlVT0EwZw==</a></p>
  
  <p>Now I understand I can allow the = sign in config.php, but I don't fully understand the security implications in doing so (it must have been disabled for a reason right?)</p>
  
  <p>Does anyone know why it might be a bad idea to allow the = symbol in URLs?</p>
  
  <p>Thanks!
  John.</p>