Home Backend Development PHP Tutorial Introducing the Factory Pattern in PHP Design Patterns_PHP Tutorial

Introducing the Factory Pattern in PHP Design Patterns_PHP Tutorial

Jul 21, 2016 pm 03:51 PM
php introduce land complex how object factory Establish operate model of able Design Patterns easy question

Question

How can you create such a "complex" object easily and conveniently without pasting and copying during operation?

Solution

Create a factory (a function or a class method) to create new objects. To understand the usefulness of factories, imagine the following differences...

code:

Copy code The code is as follows:

$connection =& new MySqlConnection($user, $password, $database);

... Make your code scalable and more concise...

Copy code The code is as follows:

$connection =& create_connection();

The latter The code snippets focus on the create_connect() factory that connects to the database. As just mentioned, the process of creating a database connection becomes a simple operation - just like the new operation. The advantage of the factory pattern lies in creating objects. Its task is to encapsulate the object creation process and then return a required new class.

Want to change the structure of the object and the way to create the object? You only need to select the object factory and change the code only once. (The function of the factory pattern is so powerful, it is at the bottom of the application, so it will continue to appear in many other complex patterns and applications.)

Sample Code

Factory Pattern Encapsulates the object creation process. You can create an object factory on the object itself or an additional factory class - it depends on your specific application. Let's look at an example of a factory object.

We found that in the following code, the database connection part appears repeatedly:

Copy the code The code is as follows:

// PHP4
class Product {
function getList() { $db =& new MysqlConnection(DB_USER, DB_PW, DB_NAME);
//...
}
function getByName($name) { $db =& new MysqlConnection(DB_USER, DB_PW, DB_NAME);
//...
}
//...
}
Why is this bad? Database connection parameters appear in too many places. When you set these parameters as constants, it means that you define them uniformly and assign values ​​to them. Obviously this approach is not very appropriate:

You can easily change the parameters for connecting to the database, but you cannot increase or change the order of these parameters unless you change all the connection code.
You cannot easily instantiate a new class to connect to another database, such as PostgresqlConnection.
This makes it difficult to test and verify the state of the connection object alone.
Using the factory design pattern, the code will be greatly improved:

Copy the code The code is as follows:

class Product {
function getList() {
$db =& $this->_getConnection();
//...
}
function &_getConnection() {
return new MysqlConnection (DB_USER, DB_PW, DB_NAME); on the _getConnection() method.




http://www.bkjia.com/PHPjc/319122.html

www.bkjia.com

http: //www.bkjia.com/PHPjc/319122.htmlTechArticleQuestion: How can you create such a "complex" object easily and conveniently without pasting and copying during operation? Solution Method creates a factory (a function or a class method) to make new...
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Roblox: Bubble Gum Simulator Infinity - How To Get And Use Royal Keys
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Nordhold: Fusion System, Explained
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1664
14
PHP Tutorial
1268
29
C# Tutorial
1248
24
Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

PHP and Python: Comparing Two Popular Programming Languages PHP and Python: Comparing Two Popular Programming Languages Apr 14, 2025 am 12:13 AM

PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

PHP in Action: Real-World Examples and Applications PHP in Action: Real-World Examples and Applications Apr 14, 2025 am 12:19 AM

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

PHP: A Key Language for Web Development PHP: A Key Language for Web Development Apr 13, 2025 am 12:08 AM

PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7

The Enduring Relevance of PHP: Is It Still Alive? The Enduring Relevance of PHP: Is It Still Alive? Apr 14, 2025 am 12:12 AM

PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers.

Explain the match expression (PHP 8 ) and how it differs from switch. Explain the match expression (PHP 8 ) and how it differs from switch. Apr 06, 2025 am 12:03 AM

In PHP8, match expressions are a new control structure that returns different results based on the value of the expression. 1) It is similar to a switch statement, but returns a value instead of an execution statement block. 2) The match expression is strictly compared (===), which improves security. 3) It avoids possible break omissions in switch statements and enhances the simplicity and readability of the code.

See all articles