PHP Cookbook - Sklar D., Trachtenberg A.

PHP Cookbook - Sklar D., Trachtenberg A. - 2002.
   The PHP Cookbook is a collection of problems, solutions, and practical examples for PHP programmers. The book contains a unique and extensive collection of best practices for everyday PHP programming dilemmas. It contains over 250 recipes, ranging from simple tasks to entire programs that demonstrate complex tasks, such as printing HTML tables and generating bar charts - a treasure trove of useful code for PHP programmers, from novices to advanced practitioners.


Copyright
Preface
Who This Book Is For
What Is in This Book
Other Resources
Conventions Used in This Book
Comments and Questions
Acknowledgments
Chapter 1. Strings
Section 1.1. Introduction
Recipe 1.2. Accessing Substrings
Recipe 1.3. Replacing Substrings
Recipe 1.4. Processing a String One Character at a Time
Recipe 1.5. Reversing a String by Word or Character
Recipe 1.6. Expanding and Compressing Tabs
Recipe 1.7. Controlling Case
Recipe 1.8. Interpolating Functions and Expressions Within Strings
Recipe 1.9. Trimming Blanks from a String
Recipe 1.10. Parsing Comma-Separated Data
Recipe 1.11. Parsing Fixed-Width Delimited Data
Recipe 1.12. Taking Strings Apart
Recipe 1.13. Wrapping Text at a Certain Line Length
Recipe 1.14. Storing Binary Data in Strings
Chapter 2. Numbers
Section 2.1. Introduction
Recipe 2.2. Checking Whether a String Contains a Valid Number
Recipe 2.3. Comparing Floating-Point Numbers
Recipe 2.4. Rounding Floating-Point Numbers
Recipe 2.5. Operating on a Series of Integers
Recipe 2.6. Generating Random Numbers Within a Range
Recipe 2.7. Generating Biased Random Numbers
Recipe 2.8. Taking Logarithms
Recipe 2.9. Calculating Exponents
Recipe 2.10. Formatting Numbers
Recipe 2.11. Printing Correct Plurals
Recipe 2.12. Calculating Trigonometric Functions
Recipe 2.13. Doing Trigonometry in Degrees, not Radians
Recipe 2.14. Handling Very Large or Very Small Numbers
Recipe 2.15. Converting Between Bases
Recipe 2.16. Calculating Using Numbers in Bases Other Than Decimal
Chapter 3. Dates and Times
Section 3.1. Introduction
Recipe 3.2. Finding the Current Date and Time
Recipe 3.3. Converting Time and Date Parts to an Epoch Timestamp
Recipe 3.4. Converting an Epoch Timestamp to Time and Date Parts
Recipe 3.5. Printing a Date or Time in a Specified Format
Recipe 3.6. Finding the Difference of Two Dates
Recipe 3.7. Finding the Difference of Two Dates with Julian Days
Recipe 3.8. Finding the Day in a Week, Month, Year, or the Week Number in a Year
Recipe 3.9. Validating a Date
Recipe 3.10. Parsing Dates and Times from Strings
Recipe 3.11. Adding to or Subtracting from a Date
Recipe 3.12. Calculating Time with Time Zones
Recipe 3.13. Accounting for Daylight Saving Time
Recipe 3.14. Generating a High-Precision Time
Recipe 3.15. Generating Time Ranges
Recipe 3.16. Using Non-Gregorian Calendars
Recipe 3.17. Program: Calendar
Chapter 4. Arrays
Section 4.1. Introduction
Recipe 4.2. Specifying an Array Not Beginning at Element 0
Recipe 4.3. Storing Multiple Elements per Key in an Array
Recipe 4.4. Initializing an Array to a Range of Integers
Recipe 4.5. Iterating Through an Array
Recipe 4.6. Deleting Elements from an Array
Recipe 4.7. Changing Array Size
Recipe 4.8. Appending One Array to Another
Recipe 4.9. Turning an Array into a String
Recipe 4.10. Printing an Array with Commas
Recipe 4.11. Checking if a Key Is in an Array
Recipe 4.12. Checking if an Element Is in an Array
Recipe 4.13. Finding the Position of an Element in an Array
Recipe 4.14. Finding Elements That Pass a Certain Test
Recipe 4.15. Finding the Largest or Smallest Valued Element in an Array
Recipe 4.16. Reversing an Array
Recipe 4.17. Sorting an Array
Recipe 4.18. Sorting an Array by a Computable Field
Recipe 4.19. Sorting Multiple Arrays
Recipe 4.20. Sorting an Array Using a Method Instead of a Function
Recipe 4.21. Randomizing an Array
Recipe 4.22. Shuffling a Deck of Cards
Recipe 4.23. Removing Duplicate Elements from an Array
Recipe 4.24. Finding the Union, Intersection, or Difference of Two Arrays
Recipe 4.25. Finding All Element Combinations of an Array
Recipe 4.26. Finding All Permutations of an Array
Recipe 4.27. Program: Printing an Array in a Horizontally Columned HTML Table
Chapter 5. Variables
Section 5.1. Introduction
Recipe 5.2. Avoiding == Versus = Confusion
Recipe 5.3. Establishing a Default Value
Recipe 5.4. Exchanging Values Without Using Temporary Variables
Recipe 5.5. Creating a Dynamic Variable Name
Recipe 5.6. Using Static Variables
Recipe 5.7. Sharing Variables Between Processes
Recipe 5.8. Encapsulating Complex Data Types as a String
Recipe 5.9. Dumping Variable Contents as Strings
Chapter 6. Functions
Section 6.1. Introduction
Recipe 6.2. Accessing Function Parameters
Recipe 6.3. Setting Default Values for Function Parameters
Recipe 6.4. Passing Values by Reference
Recipe 6.5. Using Named Parameters
Recipe 6.6. Creating Functions That Take a Variable Number of Arguments
Recipe 6.7. Returning Values by Reference
Recipe 6.8. Returning More Than One Value
Recipe 6.9. Skipping Selected Return Values
Recipe 6.10. Returning Failure
Recipe 6.11. Calling Variable Functions
Recipe 6.12. Accessing a Global Variable Inside a Function
Recipe 6.13. Creating Dynamic Functions
Chapter 7. Classes and Objects
Section 7.1. Introduction
Recipe 7.2. Instantiating Objects
Recipe 7.3. Defining Object Constructors
Recipe 7.4. Destroying an Object
Recipe 7.5. Cloning Objects
Recipe 7.6. Assigning Object References
Recipe 7.7. Calling Methods on an Object Returned by Another Method
Recipe 7.8. Accessing Overridden Methods
Recipe 7.9. Using Property Overloading
Recipe 7.10. Using Method Polymorphism
Recipe 7.11. Finding the Methods and Properties of an Object
Recipe 7.12. Adding Properties to a Base Object
Recipe 7.13. Creating a Class Dynamically
Recipe 7.14. Instantiating an Object Dynamically
Chapter 8. Web Basics
Section 8.1. Introduction
Recipe 8.2. Setting Cookies
Recipe 8.3. Reading Cookie Values
Recipe 8.4. Deleting Cookies
Recipe 8.5. Redirecting to a Different Location
Recipe 8.6. Using Session Tracking
Recipe 8.7. Storing Sessions in a Database
Recipe 8.8. Detecting Different Browsers
Recipe 8.9. Building a GET Query String
Recipe 8.10. Using HTTP Basic Authentication
Recipe 8.11. Using Cookie Authentication
Recipe 8.12. Flushing Output to the Browser
Recipe 8.13. Buffering Output to the Browser
Recipe 8.14. Compressing Web Output with gzip
Recipe 8.15. Hiding Error Messages from Users
Recipe 8.16. Tuning Error Handling
Recipe 8.17. Using a Custom Error Handler
Recipe 8.18. Logging Errors
Recipe 8.19. Eliminating "headers already sent" Errors
Recipe 8.20. Logging Debugging Information
Recipe 8.21. Reading Environment Variables
Recipe 8.22. Setting Environment Variables
Recipe 8.23. Reading Configuration Variables
Recipe 8.24. Setting Configuration Variables
Recipe 8.25. Communicating Within Apache
Recipe 8.26. Profiling Code
Recipe 8.27. Program: Website Account (De)activator
Recipe 8.28. Program: Abusive User Checker
Chapter 9. Forms
Section 9.1. Introduction
Recipe 9.2. Processing Form Input
Recipe 9.3. Validating Form Input
Recipe 9.4. Working with Multipage Forms
Recipe 9.5. Redisplaying Forms with Preserved Information and Error Messages
Recipe 9.6. Guarding Against Multiple Submission of the Same Form
Recipe 9.7. Processing Uploaded Files
Recipe 9.8. Securing PHP's Form Processing
Recipe 9.9. Escaping Control Characters from User Data
Recipe 9.10. Handling Remote Variables with Periods in Their Names
Recipe 9.11. Using Form Elements with Multiple Options
Recipe 9.12. Creating Dropdown Menus Based on the Current Date
Chapter 10. Database Access
Section 10.1. Introduction
Recipe 10.2. Using Text-File Databases
Recipe 10.3. Using DBM Databases
Recipe 10.4. Connecting to a SQL Database
Recipe 10.5. Querying a SQL Database
Recipe 10.6. Retrieving Rows Without a Loop
Recipe 10.7. Modifying Data in a SQL Database
Recipe 10.8. Repeating Queries Efficiently
Recipe 10.9. Finding the Number of Rows Returned by a Query
Recipe 10.10. Escaping Quotes
Recipe 10.11. Logging Debugging Information and Errors
Recipe 10.12. Assigning Unique ID Values Automatically
Recipe 10.13. Building Queries Programmatically
Recipe 10.14. Making Paginated Links for a Series of Records
Recipe 10.15. Caching Queries and Results
Recipe 10.16. Program: Storing a Threaded Message Board
Chapter 11. Web Automation
Section 11.1. Introduction
Recipe 11.2. Fetching a URL with the GET Method
Recipe 11.3. Fetching a URL with the POST Method
Recipe 11.4. Fetching a URL with Cookies
Recipe 11.5. Fetching a URL with Headers
Recipe 11.6. Fetching an HTTPS URL
Recipe 11.7. Debugging the Raw HTTP Exchange
Recipe 11.8. Marking Up a Web Page
Recipe 11.9. Extracting Links from an HTML File
Recipe 11.10. Converting ASCII to HTML
Recipe 11.11. Converting HTML to ASCII
Recipe 11.12. Removing HTML and PHP Tags
Recipe 11.13. Using Smarty Templates
Recipe 11.14. Parsing a Web Server Log File
Recipe 11.15. Program: Finding Stale Links
Recipe 11.16. Program: Finding Fresh Links
Chapter 12. XML
Section 12.1. Introduction
Recipe 12.2. Generating XML Manually
Recipe 12.3. Generating XML with the DOM
Recipe 12.4. Parsing XML with the DOM
Recipe 12.5. Parsing XML with SAX
Recipe 12.6. Transforming XML with XSLT
Recipe 12.7. Sending XML-RPC Requests
Recipe 12.8. Receiving XML-RPC Requests
Recipe 12.9. Sending SOAP Requests
Recipe 12.10. Receiving SOAP Requests
Recipe 12.11. Exchanging Data with WDDX
Recipe 12.12. Reading RSS Feeds
Chapter 13. Regular Expressions
Section 13.1. Introduction
Recipe 13.2. Switching From ereg to preg
Recipe 13.3. Matching Words
Recipe 13.4. Finding the nth Occurrence of a Match
Recipe 13.5. Choosing Greedy or Nongreedy Matches
Recipe 13.6. Matching a Valid Email Address
Recipe 13.7. Finding All Lines in a File That Match a Pattern
Recipe 13.8. Capturing Text Inside HTML Tags
Recipe 13.9. Escaping Special Characters in a Regular Expression
Recipe 13.10. Reading Records with a Pattern Separator
Chapter 14. Encryption and Security
Section 14.1. Introduction
Recipe 14.2. Keeping Passwords Out of Your Site Files
Recipe 14.3. Obscuring Data with Encoding
Recipe 14.4. Verifying Data with Hashes
Recipe 14.5. Storing Passwords
Recipe 14.6. Checking Password Strength
Recipe 14.7. Dealing with Lost Passwords
Recipe 14.8. Encrypting and Decrypting Data
Recipe 14.9. Storing Encrypted Data in a File or Database
Recipe 14.10. Sharing Encrypted Data with Another Web Site
Recipe 14.11. Detecting SSL
Recipe 14.12. Encrypting Email with GPG
Chapter 15. Graphics
Section 15.1. Introduction
Recipe 15.2. Drawing Lines, Rectangles, and Polygons
Recipe 15.3. Drawing Arcs, Ellipses, and Circles
Recipe 15.4. Drawing with Patterned Lines
Recipe 15.5. Drawing Text
Recipe 15.6. Drawing Centered Text
Recipe 15.7. Building Dynamic Images
Recipe 15.8. Getting and Setting a Transparent Color
Recipe 15.9. Serving Images Securely
Recipe 15.10. Program: Generating Bar Charts from Poll Results
Chapter 16. Internationalization and Localization
Section 16.1. Introduction
Recipe 16.2. Listing Available Locales
Recipe 16.3. Using a Particular Locale
Recipe 16.4. Setting the Default Locale
Recipe 16.5. Localizing Text Messages
Recipe 16.6. Localizing Dates and Times
Recipe 16.7. Localizing Currency Values
Recipe 16.8. Localizing Images
Recipe 16.9. Localizing Included Files
Recipe 16.10. Managing Localization Resources
Recipe 16.11. Using gettext
Recipe 16.12. Reading or Writing Unicode Characters
Chapter 17. Internet Services
Section 17.1. Introduction
Recipe 17.2. Sending Mail
Recipe 17.3. Sending MIME Mail
Recipe 17.4. Reading Mail with IMAP or POP3
Recipe 17.5. Posting Messages to Usenet Newsgroups
Recipe 17.6. Reading Usenet News Messages
Recipe 17.7. Getting and Putting Files with FTP
Recipe 17.8. Looking Up Addresses with LDAP
Recipe 17.9. Using LDAP for User Authentication
Recipe 17.10. Performing DNS Lookups
Recipe 17.11. Checking if a Host Is Alive
Recipe 17.12. Getting Information About a Domain Name
Chapter 18. Files
Section 18.1. Introduction
Recipe 18.2. Creating or Opening a Local File
Recipe 18.3. Creating a Temporary File
Recipe 18.4. Opening a Remote File
Recipe 18.5. Reading from Standard Input
Recipe 18.6. Reading a File into a String
Recipe 18.7. Counting Lines, Paragraphs, or Records in a File
Recipe 18.8. Processing Every Word in a File
Recipe 18.9. Reading a Particular Line in a File
Recipe 18.10. Processing a File Backward by Line or Paragraph
Recipe 18.11. Picking a Random Line from a File
Recipe 18.12. Randomizing All Lines in a File
Recipe 18.13. Processing Variable Length Text Fields
Recipe 18.14. Reading Configuration Files
Recipe 18.15. Reading from or Writing to a Specific Location in a File
Recipe 18.16. Removing the Last Line of a File
Recipe 18.17. Modifying a File in Place Without a Temporary File
Recipe 18.18. Flushing Output to a File
Recipe 18.19. Writing to Standard Output
Recipe 18.20. Writing to Many Filehandles Simultaneously
Recipe 18.21. Escaping Shell Metacharacters
Recipe 18.22. Passing Input to a Program
Recipe 18.23. Reading Standard Output from a Program
Recipe 18.24. Reading Standard Error from a Program
Recipe 18.25. Locking a File
Recipe 18.26. Reading and Writing Compressed Files
Recipe 18.27. Program: Unzip
Chapter 19. Directories
Section 19.1. Introduction
Recipe 19.2. Getting and Setting File Timestamps
Recipe 19.3. Getting File Information
Recipe 19.4. Changing File Permissions or Ownership
Recipe 19.5. Splitting a Filename into Its Component Parts
Recipe 19.6. Deleting a File
Recipe 19.7. Copying or Moving a File
Recipe 19.8. Processing All Files in a Directory
Recipe 19.9. Getting a List of Filenames Matching a Pattern
Recipe 19.10. Processing All Files in a Directory
Recipe 19.11. Making New Directories
Recipe 19.12. Removing a Directory and Its Contents
Recipe 19.13. Program: Web Server Directory Listing
Recipe 19.14. Program: Site Search
Chapter 20. Client-Side PHP
Section 20.1. Introduction
Recipe 20.2. Parsing Program Arguments
Recipe 20.3. Parsing Program Arguments with getopt
Recipe 20.4. Reading from the Keyboard
Recipe 20.5. Reading Passwords
Recipe 20.6. Displaying a GUI Widget in a Window
Recipe 20.7. Displaying Multiple GUI Widgets in a Window
Recipe 20.8. Responding to User Actions
Recipe 20.9. Displaying Menus
Recipe 20.10. Program: Command Shell
Recipe 20.11. Program: Displaying Weather Conditions
Chapter 21. PEAR
Section 21.1. Introduction
Recipe 21.2. Using the PEAR Package Manager
Recipe 21.3. Finding PEAR Packages
Recipe 21.4. Finding Information About a Package
Recipe 21.5. Installing PEAR Packages
Recipe 21.6. Installing PECL Packages
Recipe 21.7. Upgrading PEAR Packages
Recipe 21.8. Uninstalling PEAR Packages
Recipe 21.9. Documenting Classes with PHPDoc
Colophon
Index