How to customize type validation for PHP function parameters?
Customizing function parameter type validation in PHP can enforce parameter types to ensure they match expectations, thereby improving code robustness. This can be achieved by: Type hints: Declare the expected types of function parameters, mismatching types will throw an exception. Type conversion: Use the settype function or operator to convert a variable to a specified type. Type inference: PHP automatically infers variable types, such as when assigning values. Custom validation: Create a custom validation function to validate specific types (such as dates). Practical case: Demonstrate the usage of custom verification through the name verification function to ensure that the name length and format meet the requirements.
How to customize the type validation of PHP function parameters
In PHP, the type validation of function parameters allows you to force the type of the parameters passed in to ensure that they As expected. This helps improve the robustness and reliability of your code.
Type hints
PHP 7.0 introduced type hints, allowing you to declare the expected types of function parameters. You can use built-in types or create your own classes.
function sum(int $num1, int $num2) { return $num1 + $num2; }
If the incoming parameters do not match the declared type, PHP will throw a TypeError
exception.
Type conversion and type inference
PHP supports type conversion and type inference:
- ##Type conversion: Use settype
Function or cast operator converts a variable to a specified type.
- Type inference: In some cases, PHP can infer the type of a variable, such as when assigning a value.
// 类型转换 $int = (int) '10'; // 类型推断 $array = [1, 2, 3];Custom type verificationFor requirements that cannot be met by built-in types, you can create a custom verification function.
function validateDate(string $date): bool { if (preg_match('/^[0-9]{4}-[0-1][0-9]-[0-3][0-9]$/', $date)) { return true; } return false; } function formatDate(string $date) { if (!validateDate($date)) { throw new InvalidArgumentException('Invalid date format.'); } //... }Practical caseThe following is a function that verifies the name entered by the user:
function validateName(string $name): void { if (strlen($name) < 3 || strlen($name) > 25) { throw new InvalidArgumentException('Name must be between 3 and 25 characters long.'); } if (!preg_match('/^[a-zA-Z ]+$/', $name)) { throw new InvalidArgumentException('Name must contain only letters and spaces.'); } }This function uses custom validation to ensure that the incoming name meets the requirements. AdvantagesCustom type validation provides the following advantages:
- Ensure the validity of function parameters
- Improve the readability and readability of the code Maintainability
- Reduce errors through forced typing
- Facilitate unit testing and test-driven development
The above is the detailed content of How to customize type validation for PHP function parameters?. For more information, please follow other related articles on the PHP Chinese website!

PHPidentifiesauser'ssessionusingsessioncookiesandsessionIDs.1)Whensession_start()iscalled,PHPgeneratesauniquesessionIDstoredinacookienamedPHPSESSIDontheuser'sbrowser.2)ThisIDallowsPHPtoretrievesessiondatafromtheserver.

The security of PHP sessions can be achieved through the following measures: 1. Use session_regenerate_id() to regenerate the session ID when the user logs in or is an important operation. 2. Encrypt the transmission session ID through the HTTPS protocol. 3. Use session_save_path() to specify the secure directory to store session data and set permissions correctly.

PHPsessionfilesarestoredinthedirectoryspecifiedbysession.save_path,typically/tmponUnix-likesystemsorC:\Windows\TemponWindows.Tocustomizethis:1)Usesession_save_path()tosetacustomdirectory,ensuringit'swritable;2)Verifythecustomdirectoryexistsandiswrita

ToretrievedatafromaPHPsession,startthesessionwithsession_start()andaccessvariablesinthe$_SESSIONarray.Forexample:1)Startthesession:session_start().2)Retrievedata:$username=$_SESSION['username'];echo"Welcome,".$username;.Sessionsareserver-si

The steps to build an efficient shopping cart system using sessions include: 1) Understand the definition and function of the session. The session is a server-side storage mechanism used to maintain user status across requests; 2) Implement basic session management, such as adding products to the shopping cart; 3) Expand to advanced usage, supporting product quantity management and deletion; 4) Optimize performance and security, by persisting session data and using secure session identifiers.

The article explains how to create, implement, and use interfaces in PHP, focusing on their benefits for code organization and maintainability.

The article discusses the differences between crypt() and password_hash() in PHP for password hashing, focusing on their implementation, security, and suitability for modern web applications.

Article discusses preventing Cross-Site Scripting (XSS) in PHP through input validation, output encoding, and using tools like OWASP ESAPI and HTML Purifier.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

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

Hot Article

Hot Tools

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

Zend Studio 13.0.1
Powerful PHP integrated development environment
