Home arrow PHP arrow Page 4 - Using Inheritance, Polymorphism and Serialization with PHP Classes

Serializing - PHP

If you are working with classes in PHP, you will sooner or later encounter inheritance, polymorphism, and serialization. The ability to use these three will help speed up your code writing. This article covers how to use them, and more.

  1. Using Inheritance, Polymorphism and Serialization with PHP Classes
  2. Polymorphism
  3. Class Functions Without Instances
  4. Serializing
By: Jacques Noah
Rating: starstarstarstarstar / 19
August 15, 2006

print this article



Objects by their very nature are very difficult to manage as strings or numbers. This makes it difficult to store them in a database, pass along to a script, or use them generally for storing values, such as, for example, setting one as a cookie. To solve this problem, PHP has a function called serialize(). This function takes a variable and turns it into a more manageable version of itself. The syntax of this function is:

$var =serialize(object);

And to return the variable to its original state:

$object =unserialize($var);>

Both functions are a bit like encryption. If you want to hide a text you turn it into something unreadable, and then if you want to show the text you return it to its plain text state. This is more or less what serialization is about.

When using these functions make sure to include the class definitions on the page that you call unserialize().

Both functions look for two special functions when serializing objects:

serialize() checks to see whether your class has a function with the name  __sleep. If  that function is present, it  will be run prior to any serialization. It is responsible for cleaning up the object and then returning an array that includes the names of all variables of that object that should be serialized.

The purpose of the   __sleep function is to close any database connections that an object may have, commit pending data, or perform similar cleanup tasks. The function is useful for saving large objects.

unserialize() checks for the presence of a function with the name  __wakeup. If present, this function can reconstruct any resources that object may have.

The intended use of __wakeup is to re-establish any database connections that may have been lost during serialization and perform other reinitialization tasks.


While coding with functions and objects makes programming easy, it can also slow down code execution, particularly on large projects. So take care when deciding to use it.

>>> More PHP Articles          >>> More By Jacques Noah

blog comments powered by Disqus
escort Bursa Bursa escort Antalya eskort


- Hackers Compromise PHP Sites to Launch Attac...
- Red Hat, Zend Form OpenShift PaaS Alliance
- PHP IDE News
- BCD, Zend Extend PHP Partnership
- PHP FAQ Highlight
- PHP Creator Didn't Set Out to Create a Langu...
- PHP Trends Revealed in Zend Study
- PHP: Best Methods for Running Scheduled Jobs
- PHP Array Functions: array_change_key_case
- PHP array_combine Function
- PHP array_chunk Function
- PHP Closures as View Helpers: Lazy-Loading F...
- Using PHP Closures as View Helpers
- PHP File and Operating System Program Execut...
- PHP: Effects of Wrapping Code in Class Const...

Developer Shed Affiliates


Dev Shed Tutorial Topics: