Public keyword in php

Public

The «public» keyword is used in PHP to declare a class member as public, meaning that it can be accessed from anywhere in your code. In this article, we will explore the syntax and usage of the «public» keyword in depth, and provide plenty of examples to help you master this important PHP feature.

Syntax

The «public» keyword is used to declare a class member as public in PHP. Here is the basic syntax for using the «public» keyword:

class MyClass < public $myPublicVariable; public function myPublicFunction( ) < // Code block here > >

In this example, we use the «public» keyword to declare a public variable and a public function within a class.

Examples

Let’s look at some practical examples of how the «public» keyword can be used:

 // Example 1 class Car < public $model; public $color; public function __construct($model, $color) < $this->model = $model . PHP_EOL; $this->color = $color; > public function honk( ) < return "Beep beep!" . PHP_EOL; > > $myCar = new Car("Tesla", "red"); echo $myCar->model; // Output: Tesla echo $myCar->honk(); // Output: Beep beep! // Example 2 class Math < public static function add($a, $b) < return $a + $b . PHP_EOL; > public static function multiply($a, $b) < return $a * $b . PHP_EOL; > > echo Math::add(5, 10); // Output: 15 echo Math::multiply(5, 10); // Output: 50

In these examples, we use the «public» keyword to declare public variables and functions within classes, which can be accessed from anywhere in your code.

Benefits

Using the «public» keyword has several benefits, including:

• Flexibility: By using the «public» keyword to declare class members as public, you can make them accessible from anywhere in your code, which can improve the flexibility and ease of use of your classes.
• Code organization: Public members can be accessed and modified by external code, which can be useful in situations where you want to allow external code to interact with a specific class or object.

Conclusion

In conclusion, the «public» keyword is an important tool for PHP developers who are looking to create classes with public data and functionality that can be accessed from anywhere in their code. It allows you to declare class members as public, meaning that they can be accessed from anywhere in your code, and can improve the flexibility and ease of use of your classes. We hope this comprehensive guide has been helpful, and we wish you the best of luck as you continue to develop your PHP skills.

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Effective Usage of the Public Keyword in PHP

While using visibility in PHP 5 and 7 is not mandatory, it is still an option as the default setting is public visibility for everything in version 4. Additionally, incorporating visibility can improve the documentation of your code, like DOxygen. However, if you choose not to use it, it could be considered legacy code. One solution is to omit the visibility altogether.

Is there any reason to use the «public» keyword before method and member variable names? [duplicate]

Do people use the public keyword in PHP for any purpose other than clarity when naming methods and member variables?

The code is being written by humans, and it is also necessary for humans to comprehend it quickly. Unclear code can lead to additional complications.

One reason for indenting and formatting code is to aid in comprehending the code. The syntax is the only requirement for the language interpreter to recognize the code. Any additional information, including comments, is for the benefit of humans who are trying to understand the code.

Using your pseudo-code example:

Observe the simplicity of comprehending the former, in contrast to the latter.

Although both code snippets should work equivalently, it’s worth noting the difference between $d , cName , and fName . While the code will function in either scenario, it’s preferable to avoid the complexity of the second example and save time. After all, it functions correctly, doesn’t it?

The crucial aspect of coding and development is to ensure clarity. The realm of programming and computer work can be elusive and obscure, and it is essential not to overlook the fact that humans, not machines, are responsible for creating code. Therefore, there is no justification for obscuring how something works.

There is no practical distinction between including the keyword «public» or omitting it. The code does not derive any advantage from it, nor does it suffer any deterioration as a result.

Keep in mind that your code serves a dual purpose — it is meant for both the compiler and the humans responsible for maintaining it. The importance of ensuring clarity cannot be overstated.

In my view, clarity is key, and there should be no room for confusion. Additionally, I believe that member variables ought to have either protected or private access modifiers along with the necessary getters and setters.

It also helps with documenting your code, for instance, through tools like DOxygen.

The point of public/private variables and functions?, Public is typically anything you’d like to expose to whatever is using the class such as a generated value, a username/password configuration—

PHP Public, Private and Protected Methods and Properties

Public, private and protected class methods and properties. Get the rest of the FREE lessons at Duration: 8:16

Difference between functions and public functions in classes

Legacy code in PHP 4 lacked support for public , protected , and private , resulting in the use of public for all methods and omitting visibility.

Short: «public function» == «function» // true

// This is public function Foo() < $this->MyPublic(); $this->MyProtected(); $this->MyPrivate(); > 

public $attribute is equal to var $attribute; . Additionally, the PHP 4 legacy code version is also included in the var .

For PHP versions greater than or equal to 5, there is no distinction. Class methods can have public, private, or protected access modifiers. If no visibility keyword is specified, methods are automatically set to public.

In PHP, if you do not specify the visibility of a method, it will automatically be considered as public.

In object-oriented programming, class methods can have different levels of visibility, such as public, private, or protected. If no explicit visibility keyword is specified, then the method is considered to be public by default.

MyPublic(); $this->MyProtected(); $this->MyPrivate(); > > 

PHP OOP Access Modifiers, public — the property or method can be accessed from everywhere. This is default · protected — the property or method can be accessed within the class and by

Why do people often omit public/private/protected when declaring a class?

By omitting any access modifier, a function is automatically declared as public.

Is it not advisable to specify the scope of a function at all times?

To use functions as private or protected, it is necessary to specify their scope.

Is the initial method not outdated?

If PHP still accepts them, the age of a feature or its recent implementation becomes irrelevant.

In the initial stage, what is the method to distinguish private and protected functions?

To succeed, relying solely on the initial method is not possible; instead, the utilization of keywords is necessary.

1. Yes, probably.
2. Determining the age of a technique is a challenging task as it cannot be quantified easily. The technique might have been more acceptable in the earlier days when PHP classes were not as established.
3. Class methods can have public, private, or protected visibility. If a method is not declared with any visibility keyword, then it is considered as public by default.

The utilization of the visibility modifier is mandatory for both properties and methods as per the PSR-2 coding standard.

The use of public is optional as PHP 5 and 7 are backward compatible with version 4. Version 4 had public visibility as the default setting for everything.

Excluding public could lead to doubts and uncertainties since humans have a natural ability to detect patterns and inconsistencies within them. Imagine encountering a code that uses protected or private repeatedly but randomly leaves out public . Would it be considered an error or an intentional action? Is there any hidden behavior that is supposed to be triggered by it? Or is it an outdated PHP4-code that conceals compatibility issues? As a developer, it’s best to avoid such situations as it leads to unnecessary questions and complications.

Although public is not mandatory, it has been made mandatory by PSR-2. It is best to follow the standard recommendation.

It’s worth mentioning that var modifier for properties could be deprecated and replaced entirely with public . According to a proposal that includes a code analysis of Packagist’s top 10,000 packages, 94% of all classes in this code base use public exclusively. The remaining 6% of classes that use var come from four larger packages that are likely still trying to be PHP4 compatible. The «Simpletest» unit test framework targeted at PHP 4 is the most prominent among them.

To my knowledge, there isn’t any fixed code analysis for method visibility modifiers. However, it’s evident that the current trend is to eliminate outdated PHP4 practices.

Is there any reason to use the «public» keyword before method and, Is there any reason to use the public keyword before method and member variable names in PHP, or is clarity the only reason some people do it?

Why should variable has public or private or protect but function should not in a class

Familiarity with the rules of programming languages is essential to avoid unexpected behavior in your programs. For instance, if you omit visibility keywords when declaring functions within a class, they will default to having public visibility.

About the property visibility:

When defining class properties, they should be stated as either public , private , or protected . However, if var is used to declare the property, it will be defined as public .

And about the method visibility:

Class methods can be defined with one of the three keywords: public , private , or protected . Any method declared without explicitly defining its visibility is considered as public .

Regarding the defining variables, I suggest acquainting yourself with the concept of variable scope.

As per request, about the comment above regarding static vs private :

The static property of a class member is designed to handle the lifespan of a matter, irrespective of any instance of a class. Conversely, the private property deals with the matter’s accessibility, such as a matter being inaccessible when it has the private visibility.

The two concepts are distinct and can be used in conjunction with each other. However, blending these concepts may indicate a requirement for further reading on Object-Oriented Programming.

PHP public Keyword, The public keyword is an access modifier. It marks a property or method as public. Public properties and methods can be used by any code that can access the

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PHP public Keyword

Use public to declare a property that can be modified by any code:

$obj = new MyClass();
$obj->number = 5;
echo «The number is » . $obj->number;
?>

Definition and Usage

The public keyword is an access modifier. It marks a property or method as public.

Public properties and methods can be used by any code that can access the object.

Related Pages

Learn more about access modifiers in our PHP OOP — Access Modifiers Tutorial.

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