PHP is a powerful open source server-sided scripting language that can be used on a wide variety of operating systems and webservers, including Apache on UNIX and IIS on Windows.
PHP contains numerous extensions which enable you to dynamically create images and flash files, parse xml, connect to remote servers using pop, imap, ftp, http and raw sockets, natively access many database servers including PostgreSql, MySQL and Microsoft SQL Server, compress and decompress files, lookup domain names and and much more.
PHP has an excellent manual and online documentation which covers every function for every extension available.
If you are a PHP developer, I’m sure you know the str_replace function for replacing strings and are probably aware that you can pass an array of strings as the search strings and an array as the replacements. What this post looks at is a way of using a single associative array instead of two arrays, which makes dealing with a large number of replacements much more maintainable in your code.
This post is part of a series about PHP exceptions and exception handling; the first post gave a basic overview of how they work and this one shows the information that is available from the exception object when an exception is caught.
PHP’s Exception object can be extended (just as any class can be that is not declared final) which means different exception types can be thrown that handle the exception differently.
As part of a series of posts about PHP exception handling, this post looks at how to make regular errors use exception model. Normally only the newer object-oriented extensions throw exceptions but it is possible to make all errors throw an exception instead using set_error_handler.
When using the PHP PEAR DB database abstraction library it is important to escape variables just as it is when using the native database function calls. If you don’t know why this is then do a search using your favourite search engine for "sql injection". This post shows the PEAR DB way of escaping variables.
It is possible to get the value of a PHP constant dynamically using the constant() function. It takes a string value as the parameter and returns the value for the constant if it is defined.