CodeIgniter - Error Handling

Error Handling

Many  times,  while  using  application,  we  come  across  errors.  It  is  very  annoying  for  the users  if  the  errors  are  not  handled  properly.  CodeIgniter  provides  an  easy  error  handling mechanism.

You would like the messages to be displayed, when the application is in developing mode rather   than   in   production   mode   as   the   error   messages   can   be   solved   easily   at   the developing stage.

The  environment  of  your  application  can  be  changed,  by  changing  the  line  given  below from  index.php  file.  This  can  be  set  to  anything  but  normally  there  are  three  values (development, test, production) used for this purpose.

define('ENVIRONMENT',  isset($_SERVER['CI_ENV'])  ?  $_SERVER['CI_ENV']  :

'development');

Different   environment   will    require   different   levels   of   error   reporting.   By   default, development   mode   will   display   errors   and   testing   and   live   mode   will   hide   them. CodeIgniter provides three functions as shown below to handle errors.

1.   show_error() function displays errors in HTML format at the top of the screen.

2.   show_404()  function  displays  error  if  you  are  trying  to  access  a  page  which  does not exist.

3.   log_message()  function  is  used  to  write  log  messages.  This  is  useful  when  you want to write custom messages.

Logging   can   be   enabled   in   application/config/config.php   file.   Given   below   is   the screenshot of config.php file, where you can set threshold value.

You  can  find  the  log  messages  in  application/log/.  Make  sure  that  this  directory  is writable before you enable log files.

Various templates for error messages can be found in  application/views/errors/cli or

application/views/errors/html.