Zend_Loader包含不会引发异常

Question

I am finding that when Zend tries to auto load a file which doesn't exist, it throws an error which I cannot catch in a try/catch block. This happens when I use class_exists too. I have fixed the problem by hacking zend:

if ($once) {
    if (!@include_once ($filename)) {
        throw new Exception("Failed to include $filename");
    }
    // include_once $filename;
}
else {
    if (!@include ($filename)) {
        throw new Exception("Failed to include $filename");
    }
    // include $filename;
}

The commented out lines are zend's originals. Now I can catch the exception thrown when a file cannot be included. Can anybody suggest a cleaner way to do this which doesn't involve hacking zend?

I am on Zend version 1.11.10, and the code in question is Zend_Loader line 146.

Thanks.

Answer 1

instead of using include or include_once try using Zend_Loader::loadClass()

Here is the API: Zend_Loader::loadClass($class, $dirs)

An example:

Zend_Loader::loadClass('Container_Tree',
    array(
        '/home/production/mylib',
        '/home/production/myapp'
    )
);

Now the blurb on how it works:

The string specifying the class is converted to a relative path by substituting underscores with directory separators for your OS, and appending '.php' . In the example above, *'Container_Tree'* becomes 'Container\\Tree.php' on Windows.

If $dirs is a string or an array, *Zend_Loader::loadClass()* searches the directories in the order supplied. The first matching file is loaded. If the file does not exist in the specified $dirs , then the include_path for the PHP environment is searched.

If the file is not found or the class does not exist after the load, *Zend_Loader::loadClass()* throws a Zend_Exception .

This should allow you to use a try/catch block for any non-existent classes. Zend_Loader::loadFile() also has similar functionality.

Answer 2

Don't try and autoload classes that don't exist. If for some reason the class you're trying to autoload may or may not be there, wrap that part of code with a class_exists() call.

I can't think of any reason why you would want class_exists() to throw an exception on failure since it's sole purpose is to allow you to check for the existence of classes.