PHP Coding Standards Guide: Improve Code Quality and Development Efficiency

1. Introduction

PHP is a popular dynamic programming language. Besides focusing on correctness, writing standardized code is equally important. Standardized code improves readability and maintainability and facilitates teamwork and code refactoring. This article shares key PHP coding standards to boost development efficiency and code quality.

2. Naming Conventions

2.1 File Naming

PHP files should use snake_case naming with underscores, and have a .php extension. File names should be concise and clearly reflect their functionality.

// Not recommended
file.php
My_PHP_Class.class.php
<p>// Recommended<br>
user_login.php<br>
user_login_check.php<br>
MyPhpClass.php<br>

2.2 Class Naming

Class names should follow CamelCase naming, with the first letter of each word capitalized and no underscores.

// Not recommended
my_class.php
My_Class.php
My_Class_Obj.php
<p>// Recommended<br>
MyClass.php<br>
MyClassObject.php<br>

2.3 Function and Variable Naming

Function and variable names are recommended to use lowercase letters with underscores (snake_case), ensuring descriptive and readable names.

// Not recommended
myfunction()
myFunction()
MyFunction()
<p>// Recommended<br>
my_function()<br>
user_login_check()<br>

3. Code Style

3.1 Indentation

Use four spaces for indentation consistently; avoid tabs. Keep code indentation clear and uniform.

// Not recommended
if($a){
       echo $a;
}
if($b){
    echo $b;
}
<p>// Recommended<br>
if ($a) {<br>
echo $a;<br>
}<br>
if ($b) {<br>
echo $b;<br>
}<br>

3.2 Braces

Use the "K&R" style braces with opening and closing braces on separate lines. There should be a space before control structure parentheses, but no space before function declaration parentheses.

// Not recommended
if($a){
    echo $a;
}else{
    echo 0;
}
<p>// Recommended<br>
if ($a) {<br>
echo $a;<br>
} else {<br>
echo 0;<br>
}<br>

3.3 Spaces

Binary operators, commas, and semicolons should be followed by a space. Unary operators and parentheses should not have spaces between them and variable names.

// Not recommended
if($a==1){
    echo $a+1;
}
<p>// Recommended<br>
if ($a == 1) {<br>
echo $a + 1;<br>
}<br>

4. Commenting Standards

Comments are key to improving maintainability and should be concise and standardized, avoiding excessive technical jargon.

4.1 File Comments

Each file should begin with comments describing its purpose, author, and creation date.

/**
 * Filename: MyClass.php
 * Purpose: Demonstrate PHP class definition
 * Author: Tom
 * Created: September 20, 2021
 */

4.2 Function Comments

Function comments should include description, parameter explanation, and return value information to facilitate understanding and maintenance.

/**
 * Description: Calculate the sum of two numbers
 * Parameters: $a - first number, $b - second number
 * Returns: Sum of the two numbers
 */
function sum($a, $b) {
    return $a + $b;
}

4.3 Comment Style

Write comments in natural language, minimizing abbreviations and technical terms to ensure clarity.

5. Testing Standards

Testing is essential to ensure code quality and should be performed promptly after coding.

5.1 Functional Testing

Functional tests validate logic by executing defined inputs and verifying expected outputs.

5.2 Unit Testing

Write test cases for methods or functions to verify they return expected results.

5.3 Performance Testing

Stress testing evaluates system stability and load capacity.

6. Conclusion

This article comprehensively summarizes PHP coding standards, from naming conventions and code style to comments and testing, improving code quality and development efficiency. Good coding habits lay the foundation for building a high-quality codebase, hoping to assist PHP developers.