PHP Exceptions and Namespaces

I’m way too late to the PHP namespace conversation. Initially I just didn’t see the benefit of namespaces, but now I’ve seen the light.  The other issue was the production environment at work didn’t support  namespaces – I own that problem too.  Basically for way too long it was a big fail fest.

But now angel choirs are singing and I’ve seen the light.  I preface this post with these details in case you already know what I’m about to write about.

I just spent 20 minutes trying to figure out why the same pattern of code worked in one place but not another.  I’m trying to validate date strings in form submissions and had some code like this:

function validateDate()
{
	try
	{
		$dt = new \DateTime( $fieldValue );
	}
	catch( Exception $e )
	{
		return false;
	}

	return true;
}

The error I was seeing was an uncaught exception for an invalid date format.  That’s exactly what I was trying to prevent!

It took me way too long to realize that I needed to namespace the Exception class.

The solution is either to

use Exception;

at the top of my class file or to rewrite the function.

function validateDate()
{
	try
	{
		$dt = new \DateTime( $fieldValue );
	}
	catch( \Exception $e )
	{
		return false;
	}

	return true;
}

 

TLDR: Make sure you namespace the class names in your catch blocks otherwise it’s ignored and the exception is not caught.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s