PHP array deep copy method showdown: speed, memory usage and reliability

Comparison of PHP deep copy methods: Speed: clone is the fastest, followed by json_encode() json_decode(). Memory usage: json_encode() json_decode() is the least, serialize() unserialize() is the most. Reliability: All methods ensure that the original array is not affected by modifications to the copy.

PHP array deep copy method showdown: speed, memory usage and reliability

Introduction
Deep copying is crucial when dealing with multi-dimensional arrays in PHP. It creates a true copy of the array and is useful when you need to modify elements in the copy without affecting the original array. This article will compare four popular PHP deep copy methods:

Method

• ##clone
• array_map(clone, $array)
• serialize() unserialize()
• json_encode() json_decode()

Practical caseFor comparison, we create a multi-dimensional array containing 1,000 elements:

$array = range(1, 1000);
$array[] = ['a', 'b', 'c'];
$array[] = ['x' => 1, 'y' => 2];

Speed ​​testUse
microtime() to time the execution time of each method:

$time = microtime(true);
$cloneCopy = clone $array;
$microtime = microtime(true) - $time;

$time = microtime(true);
$arrayMapCloneCopy = array_map(clone, $array);
$microtime2 = microtime(true) - $time;

$time = microtime(true);
$serializeCloneCopy = unserialize(serialize($array));
$microtime3 = microtime(true) - $time;

$time = microtime(true);
$jsonCloneCopy = json_decode(json_encode($array), true);
$microtime4 = microtime(true) - $time;

Result:

Method Time (seconds)##clonearray_map(clone, $array)serialize() unserialize()##json_encode() json_decode()##Memory usage testUse

##8.9e-6
2.1e-5
8.1e-5
4.7e-5

memory_get_usage()

Measure the memory usage of each method:

$memory = memory_get_usage();
$cloneCopy = clone $array;
$memory2 = memory_get_usage() - $memory;

$memory = memory_get_usage();
$arrayMapCloneCopy = array_map(clone, $array);
$memory3 = memory_get_usage() - $memory;

$memory = memory_get_usage();
$serializeCloneCopy = unserialize(serialize($array));
$memory4 = memory_get_usage() - $memory;

$memory = memory_get_usage();
$jsonCloneCopy = json_decode(json_encode($array), true);
$memory5 = memory_get_usage() - $memory;

Result:

Method

Memory usage (bytes)##clone56,000##88,000##112,000Reliability testing

	array_map(clone, $array)
	serialize() unserialize()
##json_encode() json_decode()	64,000
	Reliability testing ensures that the original array remains unchanged when the copy is modified : $cloneCopy[0] = 100; $arrayMapCloneCopy[0] = 100; $serializeCloneCopy[0] = 100; $jsonCloneCopy[0] = 100; echo $array[0]; // 输出：1 assert($array[0] == 1); The above is the detailed content of PHP array deep copy method showdown: speed, memory usage and reliability. For more information, please follow other related articles on the PHP Chinese website! 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 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! Show More Hot Article What's New in Windows 11 KB5054979 & How to Fix Update Issues 3 weeks ago By DDD How to fix KB5055523 fails to install in Windows 11? 2 weeks ago By DDD InZoi: How To Apply To School And University 3 weeks ago By DDD How to fix KB5055518 fails to install in Windows 10? 2 weeks ago By DDD Roblox: Dead Rails – How To Summon And Defeat Nikola Tesla 4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌 Show More Hot Tools Notepad++7.3.1 Easy-to-use and free code editor SublimeText3 Chinese version Chinese version, very easy to use Zend Studio 13.0.1 Powerful PHP integrated development environment Dreamweaver CS6 Visual web development tools SublimeText3 Mac version God-level code editing software (SublimeText3) Show More Hot Topics Where is the login entrance for gmail email? 7826 15 Java Tutorial 1648 14 CakePHP Tutorial 1402 52 Laravel Tutorial 1300 25 PHP Tutorial 1239 29 Show More Related knowledge 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: 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 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. What is Cross-Site Request Forgery (CSRF) and how do you implement CSRF protection in PHP? Apr 07, 2025 am 12:02 AM In PHP, you can effectively prevent CSRF attacks by using unpredictable tokens. Specific methods include: 1. Generate and embed CSRF tokens in the form; 2. Verify the validity of the token when processing the request. PHP's Purpose: Building Dynamic Websites Apr 15, 2025 am 12:18 AM PHP is used to build dynamic websites, and its core functions include: 1. Generate dynamic content and generate web pages in real time by connecting with the database; 2. Process user interaction and form submissions, verify inputs and respond to operations; 3. Manage sessions and user authentication to provide a personalized experience; 4. Optimize performance and follow best practices to improve website efficiency and security. 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. The Future of PHP: Adaptations and Innovations Apr 11, 2025 am 12:01 AM The future of PHP will be achieved by adapting to new technology trends and introducing innovative features: 1) Adapting to cloud computing, containerization and microservice architectures, supporting Docker and Kubernetes; 2) introducing JIT compilers and enumeration types to improve performance and data processing efficiency; 3) Continuously optimize performance and promote best practices. PHP vs. Python: Understanding the Differences Apr 11, 2025 am 12:15 AM PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries. See all articles Public welfare online PHP training，Help PHP learners grow quickly！ About us Disclaimer Sitemap © php.cn All rights reserved