If you do any serious programming, whether it's in PHP 5 or some other language, you've needed to know how to handle run time errors and other "exceptional" conditions. You can do this by making your program throw generic exceptions. Or you can unlock the potential of PHP 5 and learn how to create custom exceptions, which is the subject of this four-part series.

In this first part they get you started with exceptions, showing how to throw them and catch them correctly (try/catch). They put it to good use in an example catching exceptions thrown from a MySQL connection and select.

One thing that I noticed was that although the code was well written [in the Zend Framework], implementing coding standards and best practices on many of the classes, I did notice a wrong usage of throwing exceptions (the try - catch statements).

He gives a few examples - catching a "divide by zero" the right and wrong way, how to grab/handle the message that comes along with the exception and how to define your own custom exception handler to help your code do more useful things with the errors it might throw.

While I would personally prefer an exception to be thrown in the first place, it is pretty easy to convert errors to exceptions in PHP.

His example is pretty simple - you set a custom error handler in your script that pulls in the error information and tosses an exception based on the error number the handler is given. Then you can use the try/catch method to see if your script has tossed an exception of the fatal error type. Nice simple solution to handle an interesting little problem.

A useful new feature in PHP 5 is exception handling via the try/throw/catch paradigm. An exception may be thrown and caught. If an exception is thrown in code surrounded by try, the following statements will not be executed, and the exception will be handled by the first matching catch block.

He gives a high-level overview of how Exceptions in PHP5 work and includes a simple example from his work with his DIY Framework.

So, dear readers, I received some nice emails and comments from those you have used Zend_Service_Audioscrobbler, along with having a nice email conversation with Wil Sinclair from Zend.

He still wants to "rip things up and start over", but has decided on a slightly different route - mapping the older function calls to the new ones via a __call catch and including a message stating that the older function call would be deprecated.

I just noticed today, that PHP's try catch blocks require curly braces. Anybody has an idea why it is like that? I have used curly braces by default up until now, so I just stumbled upon this weirdness today.

He includes two examples, one with a curly brace after the catch clause and the other without. This is different than several other control structures (like ifs) that don't require the curly brace when there's only the one line following it.

This coding tip demonstrates how to deal with PHP core notices and warning (aka recoverable errors) in the exception way, using try/catch statement.

IT's a simple idea, but it can definitely help you keep all of you errors in one place. The sample code he gives shows both a basic idea of the solution and a bit more complex example, providing more detailed messages for different exception types.