ZEND PHP 5 Certification STUDY GUIDE

Chapter 4
Strings And Patterns
As we mentioned in the PHP Basics chapter, strings wear many hats in PHP—far
from being relegated to mere collections of textual characters, they can be used to
store binary data of any kind—as well as text encoded in a way that PHP does not
understand natively, but that one of its extensions can manipulate directly.
String manipulation is a very important skill for every PHP developer—a fact that is
reflected in the number of exam questions that either revolve directly around strings
or that require a firm grasp on the way they work. Therefore, you should ensure that
you are very familiar with them before taking the exam.
Keep in mind, however, that strings are a vast topic; once again, we focus on the
PHP features that are most likely to be relevant to the Zend exam.
String Basics
Strings can be defined using one of several methods. Most commonly, you will encapsulate
them in single quotes or double quotes. Unlike some other languages,
these two methods behave quite differently: single quotes represent “simple strings,”
where almost all characters are used literally. Double quotes, on the other hand, encapsulate
“complex strings” that allow for special escape sequences (for example, to
insert special characters) and for variable substitution, which makes it possible to
embed the value of a variable directly in a string, without the need for any special
operator.
Licensed to 482634 - Amber Barrow (itsadmin@deakin.edu.au)