Essential Books

Dynamic Binding

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Dynamic binding, also referred as method overriding is an example of run time polymorphism that occurs when multiple classes contain different implementations of the same method, but the object that the method will be called on is unknown until run time.

This is useful if a certain condition dictates which class will be used to perform an action, where the action is named the same in both classes. 

interface Animal {
    public function makeNoise();
}

class Cat implements Animal {
    public function makeNoise
    {
        $this->meow();
    }
    ...
}

class Dog implements Animal {
    public function makeNoise {
        $this->bark();
    }
    ...
}

class Person {
    const CAT = 'cat';
    const DOG = 'dog';
private $petPreference;
private $pet;

public function isCatLover(): bool {
    return $this->petPreference == self::CAT;
}

public function isDogLover(): bool {
    return $this->petPreference == self::DOG;
}

public function setPet(Animal $pet) {
    $this->pet = $pet;
}

public function getPet(): Animal {
    return $this->pet;
}
}

if($person->isCatLover()) {
$person->setPet(new Cat());
} else if($person->isDogLover()) {
$person->setPet(new Dog());
}

$person->getPet()->makeNoise();

In the above example, the Animal class (Dog|Cat) which will makeNoise is unknown until run time depending on the property within the User class.

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Classes and objects:
* Classes and Objects
* Method Chaining in PHP
* Class Constants
* Abstract Classes
* Late static binding
* Namespacing and Autoloading
* Interfaces
* Final Keyword
* Method and Property Visibility
* Autoloading
* Calling a parent constructor when instantiating a child
* Dynamic Binding
* this self and static plus the singleton
* Defining a Basic Class
* Anonymous Classes
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0 Getting started
1 Variables
2 Arrays
3 Functional programming
4 Types
5 Autoloading primer
6 Exception handling and error reporting
7 Working with dates and time
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37 Object serialization
38 PHPDoc
39 Contributing to PHP Manual
40 String parsing
41 Loops
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46 Type juggling and non-strict comparison issues
47 Security
48 PHP MySQLi
49 Command Line Interface CLI
50 Localization
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52 Superglobal variables
53 Unit testing
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55 References
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57 Installing PHP on Windows
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59 Headers manipulation
60 Performance
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62 Installing on Linux / Unix
63 Contributing to PHP Core
64 Coding conventions
65 Using MongoDB
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67 Using SQLSRV
68 Unicode Support
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88 Manipulating an array
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90 Processing multiple arrays together
91 SPL data structures
92 Comments
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98 Recipies
99 BC Math Binary Calculator
100 Docker deployment
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103 Design patterns
104 Secure remember me
105 PHP mysqli
106 PHP built-in server
107 How to break down an URL
108 PSR
109 Contributors