How to fix canonical tags dynamically in Codeigniter?

As my website ranking is not improving, so i decided to focus on its SEO where i came to know about canonical tags. As people can acces page with different URI that effects my ranking. But codeigniter provides flexibility in URI where user can define canonical tags in easy way. Just follow the below code to make it working.

 <link rel="canonical" href="<?php echo base_url( $this->uri->uri_string() ) ; ?>" />

I hope it will help you to solve canonical issue. Kindly share it with others too. Thank You!