book

Beginning PHP 5.3

Name: Beginning PHP 5.3
Author: Matt Doyle
ISBN: 9780470413968

by Matt Doyle

October 2009

Beginner

836 pages

19h 37m

English

Wrox

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Copyright
About the Author
Credits
Acknowledgments
Introduction
Who This Book Is ForWhat This Book CoversHow This Book Is StructuredWhat You Need to Use This BookUsing the Command LineConventionsSource CodeErratap2p.wrox.com
I. Getting Up and Running with PHP
1. Introducing PHP
1.1. What Is PHP?1.2. Why Use PHP?1.3. The Evolution of PHP1.4. What's New in PHP 5.31.4.1. Namespaces1.4.2. The goto Operator1.4.3. Nowdoc Syntax1.4.4. Shorthand Form of the Ternary Operator1.4.5. Advanced Changes1.5. Summary
2. Your First PHP Script
2.1. Installing PHP2.1.1. Installing on Ubuntu Linux2.1.2. Installing on Windows2.1.3. Installing on Mac OS X2.1.4. Testing Your Installation2.1.4.1. Testing the Web Server2.1.4.2. Testing PHP2.1.5. Setting Your Time Zone2.2. Other Ways to Run PHP2.2.1. Running PHP with other Web Servers2.2.2. Compiling PHP Yourself2.2.3. Running PHP Remotely2.3. Creating Your First Script2.3.1. Embedding PHP within HTML2.3.2. Enhancing the Script Further2.3.3. Using Comments to Make Code More Readable2.4. Summary2.5. Exercise
II. Learning the Language
3. PHP Language Basics
3.1. Using Variables in PHP3.1.1. Naming Variables3.1.2. Creating Variables3.2. Understanding Data Types3.2.1. About Loose Typing3.2.2. Testing the Type of a Variable3.2.3. Changing a Variable's Data Type3.2.4. Changing Type by Casting3.3. Operators and Expressions3.3.1. Operator Types3.3.1.1. Arithmetic Operators3.3.1.2. Assignment Operators3.3.1.3. Bitwise Operators3.3.1.4. Comparison Operators3.3.1.5. Incrementing/Decrementing Operators3.3.1.6. Logical Operators3.3.1.7. String Operators3.3.2. Understanding Operator Precedence3.4. Constants3.5. Summary3.6. Exercises

4. Decisions and Loops
4.1. Making Decisions4.1.1. Simple Decisions with the if Statement4.1.2. Providing an Alternative Choice with the else Statement4.1.3. Testing One Expression Many Times with the switch Statement4.1.4. Compact Coding with the Ternary Operator4.2. Doing Repetitive Tasks with Looping4.2.1. Simple Looping with the while Statement4.2.2. Testing at the End: The do ... while Loop4.2.3. Neater Looping with the for Statement4.2.4. Escaping from Loops with the break Statement4.2.5. Skipping Loop Iterations with the continue Statement4.2.6. Creating Nested Loops4.3. Mixing Decisions and Looping with HTML4.4. Summary4.5. Exercises
5. Strings
5.1. Creating and Accessing Strings5.1.1. Including More Complex Expressions within Strings5.1.2. Using Your Own Delimiters5.1.3. Other Ways to Create Strings5.1.4. Finding the Length of a String5.1.5. Accessing Characters within a String5.2. Searching Strings5.2.1. Searching Strings with strstr()5.2.2. Locating Text with strpos() and strrpos()5.2.3. Finding the Number of Occurrences with substr_count()5.2.4. Searching for a Set of Characters with strpbrk()5.3. Replacing Text within Strings5.3.1. Replacing All Occurrences using str_replace()5.3.2. Replacing a Portion of a String with substr_replace()5.3.3. Translating Characters with strtr()5.4. Dealing with Upper- and Lowercase5.5. Formatting Strings5.5.1. General-Purpose Formatting with printf() and sprintf()5.5.2. Using Type Specifiers5.5.3. Specifying Signs5.5.4. Padding the Output5.5.5. Specifying Number Precision5.5.6. Swapping Arguments5.5.7. Storing the Result Instead of Printing It5.5.8. Trimming Strings with trim(), ltrim(), and rtrim()5.5.9. Padding Strings with str_pad()5.5.10. Wrapping Lines of Text with wordwrap()5.5.11. Formatting Numbers with number_format()5.6. Summary5.7. Exercises
6. Arrays
6.1. The Anatomy of an Array6.2. Creating Arrays6.3. Accessing Array Elements6.3.1. Changing Elements6.3.2. Outputting an Entire Array with print_r()6.3.3. Extracting a Range of Elements with array_slice()6.3.4. Counting Elements in an Array6.3.5. Stepping Through an Array6.4. Looping Through Arrays with foreach6.4.1. Using foreach to Loop Through Values6.4.2. Using foreach to Loop Through Keys and Values6.4.3. Altering Array Values with foreach6.5. Working with Multidimensional Arrays6.5.1. Creating a Multidimensional Array6.5.2. Accessing Elements of Multidimensional Arrays6.5.3. Looping Through Multidimensional Arrays6.6. Manipulating Arrays6.6.1. Sorting Arrays6.6.2. Sorting Indexed Arrays with sort() and rsort()6.6.3. Sorting Associative Arrays with asort() and arsort()6.6.4. Sorting Associative Array Keys with ksort() and krsort()6.6.5. Multi-Sorting with array_multisort()6.6.6. Adding and Removing Array Elements6.6.7. Adding and Removing Elements at the Start and End6.6.8. Adding and Removing Elements in the Middle6.6.9. Merging Arrays Together6.6.10. Converting Between Arrays and Strings6.6.11. Converting an Array to a List of Variables6.7. Summary6.8. Exercises
7. Functions
7.1. What Is a Function?7.2. Why Functions Are Useful7.3. Calling Functions7.4. Working with Variable Functions7.5. Writing Your Own Functions7.5.1. Defining Parameters7.5.2. Optional Parameters and Default Values7.5.3. Returning Values from Your Functions7.5.4. Understanding Variable Scope7.5.4.1. Working with Global Variables7.5.4.2. Using Static Variables to Preserve Values7.5.5. Creating Anonymous Functions7.6. Working with References7.6.1. Passing References to Your Own Functions7.6.2. Returning References from Your Own Functions7.7. Writing Recursive Functions7.8. Summary7.9. Exercises
8. Objects
8.1. What Is Object-Oriented Programming?8.2. Advantages of OOP8.3. Understanding Basic OOP Concepts8.3.1. Classes8.3.2. Objects8.3.3. Properties8.3.4. Methods8.4. Creating Classes and Objects in PHP8.5. Creating and Using Properties8.5.1. Understanding Property Visibility8.5.2. Declaring Properties8.5.3. Accessing Properties8.5.4. Static Properties8.5.5. Class Constants8.6. Working with Methods8.6.1. Method Visibility8.6.2. Creating a Method8.6.3. Calling Methods8.6.4. Adding Parameters and Returning Values8.6.5. Accessing Object Properties from Methods8.6.6. Static Methods8.6.7. Using Hints to Check Method Arguments8.6.8. Making Your Classes Self-Contained with Encapsulation8.7. Object Overloading with ___get(), ___set(), and ___call()8.7.1. Overloading Property Accesses with __get() and __set()8.7.2. Overloading Method Calls with __call()8.7.3. Other Overloading Methods8.8. Using Inheritance to Extend the Power of Objects8.8.1. Overriding Methods in the Parent Class8.8.2. Preserving the Functionality of the Parent Class8.8.3. Blocking Inheritance and Overrides with Final Classes and Methods8.8.4. Using Abstract Classes and Methods8.8.5. Working with Interfaces8.9. Constructors and Destructors8.9.1. Setting Up New Objects with Constructors8.9.2. Cleaning Up Objects with Destructors8.10. Automatically Loading Class Files8.11. Storing Objects as Strings8.12. Determining an Object's Class8.13. Summary8.14. Exercises
III. Using PHP in Practice
9. Handling HTML Forms with PHP
9.1. How HTML Forms Work9.2. Capturing Form Data with PHP9.2.1. Dealing Securely with Form Data9.2.2. Handling Empty Form Fields9.3. Dealing with Multi-Value Fields9.4. Generating Web Forms with PHP9.5. Storing PHP Variables in Forms9.6. Creating File Upload Forms9.6.1. Accessing Information on Uploaded Files9.6.2. Limiting the Size of File Uploads9.6.3. Storing and Using an Uploaded File9.7. Redirecting after a Form Submission9.8. Summary9.9. Exercises
10. Preserving State With Query Strings, Cookies, and Sessions
10.1. Saving State with Query Strings10.1.1. Building Query Strings10.1.2. Accessing Data in Query Strings10.2. Working with Cookies10.2.1. Cookie Components10.2.2. Setting a Cookie in PHP10.2.3. Accessing Cookies in Your Scripts10.2.4. Removing Cookies10.3. Using PHP Sessions to Store Data10.3.1. Creating a Session10.3.2. Reading and Writing Session Data10.3.3. Destroying a Session10.3.4. Passing Session IDs in Query Strings10.3.5. Changing Session Behavior10.4. Summary10.5. Exercises
11. Working with Files and Directories
11.1. Understanding Files and Directories11.2. Getting Information on Files11.2.1. Time-Related Properties11.2.2. Retrieving a Filename from a Path11.3. Opening and Closing Files11.3.1. Opening a File with fopen()11.3.2. Closing a File with fclose()11.4. Reading and Writing to Files11.4.1. Reading and Writing Strings of Characters11.4.2. Testing for the End of a File11.4.3. Reading One Line at a Time11.4.4. Reading CSV Files11.4.5. Reading and Writing Entire Files11.4.6. Random Access to File Data11.5. Working with File Permissions11.5.1. Changing Permissions11.5.2. Checking File Permissions11.6. Copying, Renaming, and Deleting Files11.7. Working with Directories11.7.1. Other Directory Functions11.7.1.1. Resetting the Directory Pointer11.7.1.2. Changing the Current Directory11.7.1.3. Creating Directories11.7.1.4. Deleting Directories11.7.1.5. Getting the Directory Path11.7.2. Working with Directory Objects11.7.3. Telling a File from a Directory11.8. Building a Text Editor11.8.1. The Text Editor Script11.8.2. Testing the Editor11.8.3. Examining the Editor Code11.8.3.1. The Main Logic11.8.3.2. The displayFileList() Function11.8.3.3. The displayEditForm() Function11.8.3.4. The saveFile() Function11.8.3.5. The createFile() Function11.8.3.6. The displayPageHeader() Function11.9. Summary11.10. Exercise
12. Introducing Databases and SQL
12.1. Deciding How to Store Data12.1.1. Database Architectures12.1.1.1. Embedded Databases12.1.1.2. Client-Server Databases12.1.2. Database Models12.1.2.1. Simple Databases12.1.2.2. Relational Databases12.1.3. Choosing a Database12.2. Understanding Relational Databases12.2.1. Normalization12.2.2. Talking to Databases with SQL12.2.2.1. MySQL Data Types12.2.2.1.1. Numeric Data Types12.2.2.1.2. Date and Time Data Types12.2.2.1.3. String Data Types12.2.2.1.4. Using Indexes and Keys12.2.2.2. Introducing SQL Statements12.2.2.2.1. Understanding the NULL Value12.3. Setting Up MySQL12.3.1. Starting the MySQL Server12.3.2. Setting Up the MySQL root Password12.4. A Quick Play with MySQL12.4.1. Creating a New Database12.4.2. Creating a Table12.4.3. Adding Data to a Table12.4.4. Reading Data from a Table12.4.5. Updating Data in a Table12.4.6. Deleting Data from a Table12.4.7. Deleting Tables and Databases12.5. Connecting to MySQL from PHP12.5.1. Making a Connection12.5.2. Handling Errors12.5.3. Reading Data12.6. Summary12.7. Exercises
13. Retrieving Data from MySQL with PHP
13.1. Setting Up the Book Club Database13.1.1. The BINARY Attribute and Collations13.1.2. The UNIQUE Constraint13.1.3. The ENUM Data Type13.1.4. The TIMESTAMP Data Type13.2. Retrieving Data with SELECT13.2.1. Limiting the Number of Rows Returned13.2.2. Sorting Results13.2.3. Using Pattern Matching for Flexible Queries13.2.4. Summarizing Data13.2.5. Eliminating Duplicate Results13.2.6. Grouping Results13.2.7. Pulling Data from Multiple Tables13.2.8. Using Aliases13.2.9. Other Useful MySQL Operators and Functions13.3. Creating a Member Record Viewer13.3.1. Creating the config.php File13.3.2. Creating the common.inc.php File13.3.3. Creating the DataObject Class File13.3.4. Building the Member Class13.3.5. Building the LogEntry Class13.3.6. Creating the view_members.php Script13.3.7. Creating the view_member.php Script13.3.8. Testing the Application13.4. Summary13.5. Exercises
14. Manipulating MySQL Data with PHP
14.1. Inserting Records14.2. Updating Records14.3. Deleting Records14.4. Building a Member Registration Application14.4.1. Adding More Common Code14.4.2. Enhancing the Member Class14.4.3. Creating the Registration Script14.4.4. Testing the Application14.5. Creating a Members' Area14.5.1. Adding an Authentication Method to the Member Class14.5.2. Enhancing the LogEntry Class to Record Page Views14.5.3. Adding More Common Code14.5.4. Writing the Login Page Script14.5.5. Creating a Logout Function14.5.6. Creating the Pages for the Members' Area14.5.7. Testing the Members' Area14.6. Creating a Member Manager Application14.6.1. Adding Update and Delete Methods to the Member Class14.6.2. Adding a Deletion Method to the LogEntry Class14.6.3. Tweaking the view_members.php Script14.6.4. Creating the view_member.php Script14.6.5. Testing the Member Manager14.7. Summary14.8. Exercises
15. Making Your Job Easier with PEAR
15.1. Installing PEAR Packages15.1.1. Testing the PEAR Package Manager on Ubuntu15.1.2. Testing PEAR using Mac OS X and MAMP15.1.3. Installing and Testing PEAR with WampServer on Windows15.1.4. Installing a Package15.1.5. Installing Dependencies15.1.6. Uninstalling Packages15.2. Using a PEAR Package15.3. Creating HTML Tables with the HTML_Table Package15.4. Web Forms the Easy Way with HTML_QuickForm15.4.1. Installing HTML_QuickForm15.4.2. Working with HTML_QuickForm15.4.3. Using Validation Rules15.5. Summary15.6. Exercises
16. PHP and the Outside World
16.1. Working with Dates and Times16.1.1. Understanding Timestamps16.1.2. Getting the Current Date and Time16.1.3. Creating Your Own Timestamps16.1.3.1. Creating Timestamps from Date and Time Values16.1.3.2. Creating Timestamps from GMT Date and Time Values16.1.3.3. Creating Timestamps from Date and Time Strings16.1.4. Extracting Date and Time Values from a Timestamp16.1.5. Formatting Date Strings16.1.6. Checking Date Values16.1.7. Working with Microseconds16.1.8. DateTime: The Future of PHP Date/Time Handling16.2. Working with HTTP16.2.1. Understanding HTTP Requests16.2.2. Exploring HTTP Responses16.2.3. Modifying an HTTP Response16.3. Getting Information from the Web Server16.4. Sending Email16.4.1. Specifying the Sender Address and Adding Headers16.4.2. Controlling the Return Path Email Address16.4.3. Sending HTML Emails16.5. Summary16.6. Exercises
17. Generating Images with PHP
17.1. Basics of Computer Graphics17.1.1. Color Theory17.1.2. Coordinate Systems17.1.3. Image Types17.2. Creating Images17.2.1. Creating a New Image17.2.2. Allocating Colors17.2.3. Outputting Images17.2.4. Drawing in an Image17.2.4.1. Drawing Individual Pixels17.2.4.2. Drawing Lines17.2.4.3. Drawing Rectangles17.2.4.4. Drawing Circles and Ellipses17.2.4.5. Drawing an Arc17.2.4.6. Drawing Polygons17.3. Manipulating Images17.3.1. Opening an Existing Image17.3.2. Applying a Watermark17.3.2.1. Copying the Watermark into the Image17.3.2.2. Working with Transparency17.3.2.3. Working with Opacity17.3.3. Creating Thumbnails17.4. Using Text in Images17.4.1. Adding Standard Text17.4.2. Using TrueType Fonts17.5. Summary17.6. Exercises
18. String Matching with Regular Expressions
18.1. What Is a Regular Expression?18.2. Pattern Matching in PHP18.3. Exploring Regular Expression Syntax18.3.1. Matching Literal Characters18.3.2. Matching Types of Characters Using Character Classes18.3.3. Matching Multiple Characters18.3.4. Greedy and Non-Greedy Matching18.3.5. Using Subpatterns to Group Patterns18.3.6. Referring to Previous Subpattern Matches18.3.7. Matching Alternative Patterns18.3.8. Using Anchors to Match At Specified Positions18.4. Finding Multiple Matches with preg_match_all()18.5. Searching Arrays with preg_grep()18.6. Replacing Text18.6.1. Replacing Text with preg_replace()18.6.2. Replacing Text Using a Callback Function18.7. Altering Matching Behavior with Pattern Modifiers18.8. Splitting a String with a Regular Expression18.9. Summary18.10. Exercises
19. Working with XML
19.1. What Is XML?19.2. XML Document Structure19.2.1. Major Parts of an XML Document19.2.2. XML Syntax Rules19.2.3. Using XML Elements and Attributes19.2.4. Valid XML Documents: DTDs and XSDs19.2.5. XHTML: An Example of DTDs in Action19.2.6. The DTDs for XHTML19.2.7. Referencing DTDs19.2.8. Specifying Namespaces19.2.9. Creating an XHTML Document19.3. Reading XML Documents with PHP19.3.1. How XML Parser Works19.3.2. Creating a New Parser19.3.3. Creating Event Handlers19.3.4. Parsing the XML Document19.3.5. Dealing with Parse Errors19.4. Writing and Manipulating XML Documents with PHP19.4.1. DOM Basics19.4.2. Creating an XML Document Using the DOM19.4.3. Manipulating XML Documents Using the DOM19.4.4. Adding Elements to an Existing Document19.4.5. Removing Elements from a Document19.4.6. Changing Nodes and Attributes19.4.7. Moving Elements Around19.5. Doing XML the Easy Way with SimpleXML19.5.1. Reading an XML Document19.5.2. Creating an XML Document19.5.3. Converting Between SimpleXML and DOM Objects19.6. Working with XSL and XSLT19.7. Summary19.8. Exercises
20. Writing High-Quality Code
20.1. Writing Modular Code20.1.1. Including Files20.1.2. Including a File Only Once20.1.3. Working with Include Paths20.1.4. Dynamic Includes20.1.5. Using Namespaces to Avoid Clashes20.2. Using Coding Standards for Consistency20.3. Documenting Your Code20.3.1. Writing Good Comments20.3.2. Using phpDocumentor to Generate External Documentation20.4. Checking Input and Encoding Output20.4.1. Checking Input20.4.2. Encoding Output20.5. Handling Errors20.5.1. Understanding Error Levels20.5.2. Triggering Errors20.5.3. Controlling Where Error Messages Are Sent20.5.4. Logging Your Own Error Messages20.5.5. Letting Your Script Handle Errors20.5.6. Fine-Tuning Error Reporting20.5.7. Using Exception Objects to Handle Errors20.5.8. Throwing Exceptions20.5.9. Catching Exceptions20.5.10. Creating Your Own Exception Classes20.6. Separating Application Logic from Presentation Logic20.7. Automated Code Testing with PHPUnit20.8. Summary20.9. Exercises
A. Solutions to Exercises
A.1. Chapter 2A.1.1. Exercise SolutionA.2. Chapter 3A.2.1. Exercise 1 SolutionA.2.2. Exercise 2 SolutionA.3. Chapter 4A.3.1. Exercise 1 SolutionA.3.2. Exercise 2 SolutionA.4. Chapter 5A.4.1. Exercise 1 SolutionA.4.2. Exercise 2 SolutionA.5. Chapter 6A.5.1. Exercise 1 SolutionA.5.2. Exercise 2 SolutionA.6. Chapter 7A.6.1. Exercise 1 SolutionA.6.2. Exercise 2 SolutionA.7. Chapter 8A.7.1. Exercise 1 SolutionA.7.2. Exercise 2 SolutionA.8. Chapter 9A.8.1. Exercise 1 SolutionA.8.2. Exercise 2 SolutionA.9. Chapter 10A.9.1. Exercise 1 SolutionA.9.2. Exercise 2 SolutionA.10. Chapter 11A.10.1. Exercise SolutionA.11. Chapter 12A.11.1. Exercise 1 SolutionA.11.2. Exercise 2 SolutionA.12. Chapter 13A.12.1. Exercise 1 SolutionA.12.2. Exercise 2 SolutionA.13. Chapter 14A.13.1. Exercise 1 SolutionA.13.2. Exercise 2 SolutionA.14. Chapter 15A.14.1. Exercise 1 SolutionA.14.2. Exercise 2 SolutionA.15. Chapter 16A.15.1. Exercise 1 SolutionA.15.2. Exercise 2 SolutionA.16. Chapter 17A.16.1. Exercise 1 SolutionA.16.2. Exercise 2 SolutionA.17. Chapter 18A.17.1. Exercise 1 SolutionA.17.2. Exercise 2 SolutionA.18. Chapter 19A.18.1. Exercise 1 SolutionA.18.2. Exercise 2 SolutionA.19. Chapter 20A.19.1. Exercise 1 SolutionA.19.2. Exercise 2 Solution
B. Configuring PHP
B.1. About php.iniB.2. php.ini OptionsB.3. Language OptionsB.4. MiscellaneousB.5. Resource LimitsB.6. Error Handling and LoggingB.7. Data HandlingB.8. Paths and DirectoriesB.9. File UploadsB.10. Fopen WrappersB.11. Dynamic ExtensionsB.12. Module Settings
C. Alternatives to MySQL
C.1. SQLiteC.2. PostgreSQLC.3. dbm-Style DatabasesC.4. OracleC.5. ODBCC.6. Other Databases Supported by PHP
D. Using PHP from the Command Line
D.1. Running Command-Line PHP ScriptsD.2. Passing Arguments to Command-Line ScriptsD.3. Creating Interactive ScriptsD.4. Scheduling PHP Command-Line ScriptsD.5. Useful Command-Line OptionsD.6. Wrapping Up

Content preview from Beginning PHP 5.3

Chapter 4. Decisions and Loops

So far, you've learned that PHP lets you create dynamic Web pages, and you've explored some fundamental language concepts such as variables, data types, operators, expressions, and constants.

However, all the scripts you've written have worked in a linear fashion: the PHP engine starts at the first line of the script, and works its way down until it reaches the end. Things get a lot more interesting when you start introducing decisions and loops.

A decision lets you run either one section of code or another, based on the results of a specific test. Meanwhile, a loop lets you run the same section of code over and over again until a specific condition is met.

By using decisions and loops, you add a lot of power to your scripts, and you can make them truly dynamic. Now you can display different page content to your visitors based on where they live, or what buttons they've clicked on your form, or whether or not they're logged in to your site.

In this chapter you explore the various ways that you can write decision-making and looping code in PHP. You learn about:

Making decisions with the if, else, and switch statements
Writing compact decision code with the ternary operator
Looping with the do, while, and for statements
Altering loops with the break and continue statements
Nesting loops inside each other
Using decisions and looping to display HTML

Once you've learned the concepts in this chapter, you'll be well on your way to building useful, adaptable PHP scripts. ...

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Beginning PHP 5.3

by Matt Doyle

Chapter 4. Decisions and Loops

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