Specifications

FIGURE 23.1

You can give friendlier error messages than PHP if you use your own error handler.

This custom error handler does not do any more than the default behavior. Because this code

is written by you, you can make it do anything. It gives you a choice about what to tell your

visitors when something goes wrong and how to present that information so that it fits the

rest of the site. More importantly, it gives you flexibility to decide what happens. Should the

script continue? Should a message be logged or displayed? Should tech support be alerted

automatically?

It is important to note that your error handler will not have the responsibility for dealing with

all error types. Some errors, such as parse errors and fatal runtime errors will still trigger the

default behavior. If this concerns you, make sure that you check parameters carefully before

passing them to a function that can generate fatal errors and trigger your own E_USER_ERROR

level error if your parameters are going to cause failure.

Remote Debugging

Version 3 of PHP included a remote debugger. The purpose of this was to send detailed infor-

mation about errors and events while your code executed to a port that could be monitored.

This functionality is not available in PHP version 4 without purchasing the Zend IDE.

Building Practical PHP and MySQL Projects

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