PHP for the Web: Visual QuickStart Guide, Third Edition

5 Using Strings

As introduced in Chapter 2, “Variables,” the second category of variables used by PHP is strings—a collection of characters enclosed within either single or double quotation marks. A string variable may consist of a single letter, a word, a sentence, a paragraph, HTML code, or even a jumble of nonsensical letters, numbers, and symbols (which might represent a password). Strings may be the most common variable type used in PHP.

Passwords, names, email addresses, comments, and similar input from HTML forms all become strings in your PHP script. You would have witnessed this behavior if you tried the feedback.html and handle_form.php pages in Chapter 3, “HTML Forms and PHP.”

This chapter covers PHP’s most basic built-in functions ...