“Fatal error: Cannot redeclare class” … but the class was not declared

问题

(I'm using Joomla v1.5.15 and PHP 5.3.4)

I have tested the solutions found in this and others developer forums, but I still having the same error.

Requiring file => contratolocal.php

...
if ( !class_exists('MTIHelperEstadosLocal') )
    JLoader::import('helpers.estados.estadoslocal', JPATH_COMPONENT, false);

class MTIControllerContratoLocal extends MTIController
{
...

Required file => estadoslocal.php

...
class MTIHelperEstadosLocal extends MTIHelperEstados
{
...

"JLoader::import" is used normally in Joomla to import files to the actual script. Anyway, I tried "include/require_once" php methods also without success.

I got the same error with every solution that I tried:

"Fatal error: Cannot redeclare class MTIHelperEstadosLocal"

The class is not declarated previously becouse I can't use the class without the import and if I print the returned array of the "get_declared_classes()" php method, this class isn't there.

What going on?

Thanks

回答1:

Solved.

There were 2 problems:

1. In my project there are some helpers that include other files, and one of them has a require_once previously done.

2. The require_once doesn't avoid the second include, and I had to code every require_once in a condition:

   if ( !class_exists('MTIHelperEstadosLocal') )

来源：https://stackoverflow.com/questions/8668630/fatal-error-cannot-redeclare-class-but-the-class-was-not-declared