Question: Is there any way to set my `base_url()` from my controller's ? 

OR Can I set my `base_url` `Dynamic` ?

How can I achieved this ?

Answer: 
After Searching i found the solution .
yes we can change the base\_url from our controller as

```
$this->config->set_item('base_url','http://example.com/xyz') ;

```

Ref: [User Guide](http://ellislab.com/codeigniter/user-guide/libraries/config.html)

May this answer should help some one .
The base url is set in your config file, so you can update the $config variable from your controllers before you call `base_url()`.

<http://codeigniter.com/forums/viewthread/60181/>

**EDIT**

Of course, I haven't tested this, so don't know if the overwrite will actually work as expected.

You could always extend the url helper with your own class and override the base\_url method.