Using the PHP Function Pack

The php function pack converts data into binary string based on the format argument. This is useful for serializing data and communicating with external systems that require this type of information. While most low level functionality like reading and writing graphics is taken care of by 3rd party libraries in PHP, it's important to understand the basics of how to do this yourself in case the need arises.

One of the best ways to do this is by using the mb_* functions. These functions are a bit different than the standard string functions. They use an internal encoding instead of a UTF-8 encoded string, and they also add padding and alignment to the output.

Another important feature of these functions is their ability to take a list of arguments and turn them into a single string. This is especially useful when working with large data sets. This is an excellent alternative to putting all the arguments in a list and calling the string() function on them.

Lastly, it's important to note that the pack() and unpack() functions work differently than PERL's versions. PERL's version supports arrays as arguments, while PHP's doesn't.

In addition to the mb_* functions, you can also create your own class autoloader by registering a function with the spl_autoload_register() core PHP function. This function takes a string class name, looks for a file in the web root that matches it, and loads that file. This makes it much easier to handle large class structures in your code.