The Difference Between self::, static::, and parent:: in PHP

 In PHP, self::, static::, and parent:: are used to refer to different contexts in Object-Oriented Programming (OOP). Here's a detailed explanation of each, along with examples:

1. self::

self:: is used to access static properties and methods from within the same class. It refers to the class in which it is used, and does not account for inheritance. Therefore, it is a static reference to the class where the method or property was defined.

Example:

php
class A {
    public static function who() {
        echo __CLASS__;
    }
    public static function test() {
        self::who();
    }
}
class B extends A {
    public static function who() {
        echo __CLASS__;
    }
}
B::test(); // Outputs: A

In this example, self::who() in class A refers to class A's who method, so the output is A.

2. static::

static:: is similar to self::, but it is late static bound. This means that it refers to the class that was called at runtime, rather than the class where the method was defined. It allows methods in parent classes to call methods that might be overridden in child classes.

Example:

php
class A {
    public static function who() {
        echo __CLASS__;
    }
    public static function test() {
        static::who();
    }
}
class B extends A {
    public static function who() {
        echo __CLASS__;
    }
}
B::test(); // Outputs: B

In this example, static::who() in class A refers to class B's who method because test was called on class B, so the output is B.

3. parent::

parent:: is used to refer to the parent class from within a child class. It allows a child class to call a method or access a property that is defined in its parent class.

Example:

php
class A {
    public static function who() {
        echo __CLASS__;
    }

    public static function test() {
        self::who();
    }
}

class B extends A {
    public static function who() {
        echo __CLASS__;
    }

    public static function test() {
        parent::test(); // Calls A::test()
    }
}

B::test(); // Outputs: A

In this example, parent::test() in class B calls the test method from class A, which uses self::who(), resulting in the output A.

Summary

• self::: Refers to the class in which it is used. It does not consider inheritance and is resolved at compile-time.
• static::: Refers to the class that was called at runtime, allowing for late static binding. This means it can be used to call methods that may be overridden in subclasses.
• parent::: Refers to the parent class of the class in which it is used. It is used to call methods or access properties from the parent class.

Understanding these differences is crucial for correctly implementing inheritance and polymorphism in PHP OOP.

task by vying softwares

i completed task for below questions, please check zip file

1, Create a script to import the csv file having the employee details into the DB and show them up in a web page.

2. Create programs to add/modify/delete of employee details with employee's manager into the DB and show them onto web page. Add csv export for employee details]

task by aqua web

 Test Project Description: You are tasked with building a job board application using Laravel. The application should allow users to post job listings, search for jobs, and apply for them. Requirements: 1. Job Listings: • Users should be able to create, read, update, and delete job listings. • Each job listing should have a title, description, company name, location, and job type (e.g., full-time, part-time, contract). • Implement pagination for displaying job listings. 2. User Authentication: • Users should be able to register, login, and logout. • Authentication should be implemented using Laravel's built-in authentication system. 3. Job Search: • Implement a search functionality that allows users to search for jobs based on keywords, location, or job type. • Display search results with relevant job listings. 4. Job Applications: • Users should be able to apply for job listings. • Upon applying, the user's application details (e.g., resume, cover letter) should be stored. 5. Email Notifications: • Send email notifications to users when they successfully post a job listing and when someone applies for their job listing. • Use Laravel's built-in mail functionality for sending emails. 6. Admin Panel: • Implement an admin panel where administrators can manage job listings and user applications. • Administrators should be able to view all job listings, approve/ delete job listings, and view job applications. Instructions: 1. Set up a new Laravel project. 2. Implement the necessary database tables, models, and relationships for job listings, users, and job applications. 3. Implement user authentication using Laravel's built-in authentication system. 4. Push your code to a public Git repository (e.g., GitHub) and provide the link to the repository. 5. Include clear instructions on how to run the project locally and any necessary setup steps in the README file. 6. Document any assumptions you made during development and any additional features or improvements you would make given more time.

task by momentum

 Please complete the below requirements

1. The user has a company and the company has multiple fields
1. Name
2. Business Category
3. Link
4. Phone
5. Email
6. Website
7. Country
8. Address
9. Postal code
2. The task is adding 5 extra dynamic fields in the form
3. Label and values can be editable in dynamic and static fields
4. Save values in the company table in Laravel
5. After saving labels, values and new extra fields show on the company update page

laravel routes

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