PHP — Cookies

🐘 PHP 8.2+ 🟢 Lesson 22 of 52 📂 Phase 08: Sessions, Cookies & Auth 📅 2026 Edition
📌 Covered in this chapter: Cookie ante enti? · setcookie() function · Reading cookies ($_COOKIE) · Expiration time · Path & Domain · Secure flag · HttpOnly flag · SameSite attribute · Deleting cookies

Welcome to PHP — Cookies in our PHP Complete Masterclass! Set client-side HTTP cookies using setcookie(), configuring secure flags HttpOnly, Secure, and SameSite attributes.

1Cookies — Conceptual Theory & Architecture

In modern PHP 8.2+ web engineering, mastering Cookies is essential for building fast, secure, and maintainable backend applications, microservices, and web API platforms.

💡 Core Architecture & Principles

PHP handles cookies through strict ZEND Engine execution, explicit type checking, and modern PSR standard conventions. Key topics covered in this lesson:

  • Cookie ante enti?: Fundamental PHP web concept for production code design.
  • setcookie() function: Fundamental PHP web concept for production code design.
  • Reading cookies ($_COOKIE): Fundamental PHP web concept for production code design.
  • Expiration time: Fundamental PHP web concept for production code design.
  • Path & Domain: Fundamental PHP web concept for production code design.
  • Secure flag: Fundamental PHP web concept for production code design.
  • HttpOnly flag: Fundamental PHP web concept for production code design.
  • SameSite attribute: Fundamental PHP web concept for production code design.
  • Deleting cookies: Fundamental PHP web concept for production code design.
PHP ZEND Engine Execution Pipeline for Cookies: [ PHP File (.php) ] ──> [ Lexer & Parser ] ──> [ AST & Opcodes ] │ ▼ [ Client HTML/JSON Output ] <── [ SAPI Stream ] <── [ OPcache & Zend Executor ]
2Production Code Implementation
PHP — Production Example ▶ Run in PHP Compiler
PHP ConstructTechnical Purpose & Execution Behavior
<?phpOpening tag instructing the web server to interpret code via the PHP ZEND engine.
declare(strict_types=1);Enforces strict type checking for function parameters and return types across the file.
htmlspecialchars()Escapes special HTML characters to protect applications from Cross-Site Scripting (XSS).
3Security & Best Practices
⚠️ Security Traps & Best Practices
  • Never trust user input from superglobals ($_GET, $_POST, $_COOKIE). Always validate and sanitize before processing.
  • Set secure session cookie attributes: session.cookie_httponly = 1, session.cookie_secure = 1, session.cookie_samesite = 'Lax'.
  • Turn off display_errors in production (ini_set('display_errors', '0')) and log errors securely to files.
💻 Live PHP Code Execution

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Written by Our Compiler Technical Editorial Team
Reviewed for accuracy & tested on PHP 8.2+ · Last updated August 2026