HTTP Method Spoofing
When working with HTML forms you can only use GET or POST HTTP verbs. In most cases, this is just fine. However, to support REST-ful routing you need to support other, more correct, verbs, like DELETE or PUT. Since the browsers don’t support this, CodeIgniter provides you with a way to spoof the method that is being used. This allows you to make a POST request, but tell the application that it should be treated as a different request type.
To spoof the method, a hidden input is added to the form with the name of
_method. It’s value is the HTTP verb
that you want the request to be:
<form action="" method="post">
<input type="hidden" name="_method" value="PUT">
This form is converted into a PUT request and is a true PUT request as far as the routing and the IncomingRequest class are concerned.
The form that you are using must be a POST request. GET requests cannot be spoofed.
Be sure to check your web server’s configuration as some servers do not support all HTTP verbs with the default configuration, and must have additional packages enabled to work.