Codeigniter Easy to Learn or not?

[eluser]AM-Info[/eluser]
Hello,
I am new in web development. I want to learn Codeigniter Development.
Codeigniter Developers

[eluser]AM-Info[/eluser]
Codeigniter is necessary for web development.

[eluser]Unknown[/eluser]
I have been trying to integrate Facebook authentication into my Codeigniter based website. I have included the Facebook PHP SDK as a library and that seems to connect just fine, however when I use the getUser method in the SDK a 0 is returned indicating that I am not logged in (except that I am logged in to facebook).
I had lot many confusion and i was helpless. What i need to do further?
web development services

[eluser]SPeed_FANat1c[/eluser]
@AM-Info

if you have programed with other labguage, learning CI is not dificult

[eluser]InsiteFX[/eluser]
For Ajax GET

Code:

// ./application/config/config.php
$config['permitted_uri_chars'] = 'a-z 0-9~%?=&.:_\-';    // See the ?=&

For the GET variables CI clears them on start.

Code:

// ./application/core/MY_Input.php
class MY_Input extends CI_Input {

/**
  * --------------------------------------------------------------------
  * Class variables - public, private, protected and static.
  * --------------------------------------------------------------------
  */

// -----------------------------------------------------------------------

/**
  * _sanitize_globals()
  *
  * Some Workaround:
  *
  * 1. If you want to accept GET data in your controller’s index method.. have to use
  * - http://localhost/myapp/mycontroller/index/?possible=yes
  *
  * @access public
  */
public function _sanitize_globals()
{
  $this->allow_get_array = TRUE;

  parent::_sanitize_globals();
}

} // End of Class.

[eluser]AM-Info[/eluser]
@ InsiteFX
Thanks....
Codeigniter Developers

[eluser]Unknown[/eluser]
geting same problem

I have been trying to integrate Facebook authentication into my Codeigniter based website. I have included the Facebook PHP SDK as a library and that seems to connect just fine, however when I use the getUser method in the SDK a 0 is returned indicating that I am not logged in (except that I am logged in to facebook).
I had lot many confusion and i was helpless. What i need to do further?