PHP
Notes for ProfessionalsPHP
Notes for Professionals
400+ pages
of professional hints and tricks
GoalKicker.com
Free Programming Books
Disclaimer
This is an unocial free book created for educational purposes and is
not aliated with ocial PHP group(s) or company(s).
All trademarks and registered trademarks are
the property of their respective owners
Contents
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Chapter 1: Getting started with PHP
Section 1.1: HTML output from web server
Section 1.2: Hello, World!
Section 1.3: Non-HTML output from web server
Section 1.4: PHP built-in server
Section 1.5: PHP CLI
Section 1.6: Instruction Separation
Section 1.7: PHP Tags
Chapter 2: Variables
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Section 2.1: Accessing A Variable Dynamically By Name (Variable variables)
Section 2.2: Data Types
Section 2.3: Global variable best practices
Section 2.4: Default values of uninitialized variables
Section 2.5: Variable Value Truthiness and Identical Operator
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Chapter 3: Variable Scope
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Section 3.1: Superglobal variables
Section 3.2: Static properties and variables
Section 3.3: User-defined global variables
Chapter 4: Superglobal Variables PHP
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Section 4.1: Suberglobals explained
Section 4.2: PHP5 SuperGlobals
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Chapter 5: Outputting the Value of a Variable
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Section 5.1: echo and print
Section 5.2: Outputting a structured view of arrays and objects
Section 5.3: String concatenation with echo
Section 5.4: printf vs sprintf
Section 5.5: Outputting large integers
Section 5.6: Output a Multidimensional Array with index and value and print into the table
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Chapter 6: Constants
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Section 6.1: Defining constants
Section 6.2: Class Constants
Section 6.3: Checking if constant is defined
Section 6.4: Using constants
Section 6.5: Constant arrays
Chapter 7: Magic Constants
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Section 7.1: Dierence between __FUNCTION__ and __METHOD__
Section 7.2: Dierence between __CLASS__, get_class() and get_called_class()
Section 7.3: File & Directory Constants
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Chapter 8: Comments
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Section 8.1: Single Line Comments
Section 8.2: Multi Line Comments
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Chapter 9: Types
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Section 9.1: Type Comparison
Section 9.2: Boolean
Section 9.3: Float
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Section 9.4: Strings
Section 9.5: Callable
Section 9.6: Resources
Section 9.7: Type Casting
Section 9.8: Type Juggling
Section 9.9: Null
Section 9.10: Integers
Chapter 10: Operators
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Section 10.1: Null Coalescing Operator (??)
Section 10.2: Spaceship Operator (<=>)
Section 10.3: Execution Operator (``)
Section 10.4: Incrementing (++) and Decrementing Operators (--)
Section 10.5: Ternary Operator (?:)
Section 10.6: Logical Operators (&&/AND and ||/OR)
Section 10.7: String Operators (. and .=)
Section 10.8: Object and Class Operators
Section 10.9: Combined Assignment (+= etc)
Section 10.10: Altering operator precedence (with parentheses)
Section 10.11: Basic Assignment (=)
Section 10.12: Association
Section 10.13: Comparison Operators
Section 10.14: Bitwise Operators
Section 10.15: instanceof (type operator)
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Chapter 11: References
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Section 11.1: Assign by Reference
Section 11.2: Return by Reference
Section 11.3: Pass by Reference
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Chapter 12: Arrays
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Section 12.1: Initializing an Array
Section 12.2: Check if key exists
Section 12.3: Validating the array type
Section 12.4: Creating an array of variables
Section 12.5: Checking if a value exists in array
Section 12.6: ArrayAccess and Iterator Interfaces
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Chapter 13: Array iteration
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Section 13.1: Iterating multiple arrays together
Section 13.2: Using an incremental index
Section 13.3: Using internal array pointers
Section 13.4: Using foreach
Section 13.5: Using ArrayObject Iterator
Chapter 14: Executing Upon an Array
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Section 14.1: Applying a function to each element of an array
Section 14.2: Split array into chunks
Section 14.3: Imploding an array into string
Section 14.4: "Destructuring" arrays using list()
Section 14.5: array_reduce
Section 14.6: Push a Value on an Array
Chapter 15: Manipulating an Array
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Section 15.1: Filtering an array
Section 15.2: Removing elements from an array
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Section 15.3: Sorting an Array
Section 15.4: Whitelist only some array keys
Section 15.5: Adding element to start of array
Section 15.6: Exchange values with keys
Section 15.7: Merge two arrays into one array
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Chapter 16: Processing Multiple Arrays Together
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Section 16.1: Array intersection
Section 16.2: Merge or concatenate arrays
Section 16.3: Changing a multidimensional array to associative array
Section 16.4: Combining two arrays (keys from one, values from another)
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Chapter 17: Datetime Class
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Section 17.1: Create Immutable version of DateTime from Mutable prior PHP 5.6
Section 17.2: Add or Subtract Date Intervals
Section 17.3: getTimestamp
Section 17.4: setDate
Section 17.5: Create DateTime from custom format
Section 17.6: Printing DateTimes
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Chapter 18: Working with Dates and Time
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Section 18.1: Getting the dierence between two dates / times
Section 18.2: Convert a date into another format
Section 18.3: Parse English date descriptions into a Date format
Section 18.4: Using Predefined Constants for Date Format
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Chapter 19: Control Structures
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Section 19.1: if else
Section 19.2: Alternative syntax for control structures
Section 19.3: while
Section 19.4: do-while
Section 19.5: goto
Section 19.6: declare
Section 19.7: include & require
Section 19.8: return
Section 19.9: for
Section 19.10: foreach
Section 19.11: if elseif else
Section 19.12: if
Section 19.13: switch
Chapter 20: Loops
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Section 20.1: continue
Section 20.2: break
Section 20.3: foreach
Section 20.4: do...while
Section 20.5: for
Section 20.6: while
Chapter 21: Functions
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Section 21.1: Variable-length argument lists
Section 21.2: Optional Parameters
Section 21.3: Passing Arguments by Reference
Section 21.4: Basic Function Usage
Section 21.5: Function Scope
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Chapter 22: Functional Programming
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Section 22.1: Closures
Section 22.2: Assignment to variables
Section 22.3: Objects as a function
Section 22.4: Using outside variables
Section 22.5: Anonymous function
Section 22.6: Pure functions
Section 22.7: Common functional methods in PHP
Section 22.8: Using built-in functions as callbacks
Section 22.9: Scope
Section 22.10: Passing a callback function as a parameter
Chapter 23: Alternative Syntax for Control Structures
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Section 23.1: Alternative if/else statement
Section 23.2: Alternative for statement
Section 23.3: Alternative while statement
Section 23.4: Alternative foreach statement
Section 23.5: Alternative switch statement
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Chapter 24: String formatting
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Section 24.1: String interpolation
Section 24.2: Extracting/replacing substrings
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Chapter 25: String Parsing
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Section 25.1: Splitting a string by separators
Section 25.2: Substring
Section 25.3: Searching a substring with strpos
Section 25.4: Parsing string using regular expressions
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Chapter 26: Classes and Objects
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Section 26.1: Class Constants
Section 26.2: Abstract Classes
Section 26.3: Late static binding
Section 26.4: Namespacing and Autoloading
Section 26.5: Method and Property Visibility
Section 26.6: Interfaces
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Section 26.7: Final Keyword
Section 26.8: Autoloading
Section 26.9: Calling a parent constructor when instantiating a child
Section 26.10: Dynamic Binding
Section 26.11: $this, self and static plus the singleton
Section 26.12: Defining a Basic Class
Section 26.13: Anonymous Classes
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Chapter 27: Namespaces
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Section 27.1: Declaring namespaces
Section 27.2: Referencing a class or function in a namespace
Section 27.3: Declaring sub-namespaces
Section 27.4: What are Namespaces?
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Chapter 28: Sessions
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Section 28.1: session_start() Options
Section 28.2: Session Locking
Section 28.3: Manipulating session data
Section 28.4: Destroy an entire session
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Section 28.5: Safe Session Start With no Errors
Section 28.6: Session name
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Chapter 29: Cookies
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Section 29.1: Modifying a Cookie
Section 29.2: Setting a Cookie
Section 29.3: Checking if a Cookie is Set
Section 29.4: Removing a Cookie
Section 29.5: Retrieving a Cookie
Chapter 30: Output Buering
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Section 30.1: Basic usage getting content between buers and clearing
Section 30.2: Processing the buer via a callback
Section 30.3: Nested output buers
Section 30.4: Running output buer before any content
Section 30.5: Stream output to client
Section 30.6: Using Output buer to store contents in a file, useful for reports, invoices etc
Section 30.7: Typical usage and reasons for using ob_start
Section 30.8: Capturing the output buer to re-use later
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Chapter 31: JSON
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Section 31.1: Decoding a JSON string
Section 31.2: Encoding a JSON string
Section 31.3: Debugging JSON errors
Section 31.4: Using JsonSerializable in an Object
Section 31.5: Header json and the returned response
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Chapter 32: SOAP Client
Section 32.1: WSDL Mode
Section 32.2: Non-WSDL Mode
Section 32.3: Classmaps
Section 32.4: Tracing SOAP request and response
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