Home Backend Development PHP Problem php array short division

php array short division

May 23, 2023 pm 02:26 PM

In PHP programming, array is a very important data structure. In array processing, we often encounter the need to delete specified elements. Normally, we will choose to use the unset keyword to delete the specified array element, but sometimes we need to perform a simpler way, which is the so-called "short division".

Short division, as the name suggests, refers to a simple and efficient array deletion method. Different from the cumbersome use of the unset function, short division allows us to complete the deletion of array elements in one line of code. So, what exactly is short division? How is it achieved?

1. The definition of short division

In layman's terms, short division is a technique to delete an element by copying a part of an array.

To put it simply, short division is to copy the array elements before and after the element that needs to be deleted to another array to achieve the purpose of "deleting" the element.

2. Implementation of short division

The implementation of short division is very simple. We can implement it through the following code:

$del_index = 1; //Under the element that needs to be deleted Standard
$new_array = array_merge(array_slice($array, 0, $del_index),array_slice($array, $del_index 1));

Among them, $array is the original array and $del_index needs to be deleted The subscript of the element, $new_array is the new array after deleting the specified element.

In the above code, we use the array_slice() function to perform array cutting. The first parameter is the array that needs to be cut, and the second parameter is the starting index that needs to be cut. The three parameters are the length to be cut. In the above code, we cut twice and merge the arrays into a new array through the array_merge() function.

3. Advantages of short division

Compared with using unset to delete elements, short division has the following three advantages:

1. Simple and easy to understand. Using short division, you only need one line of code to complete the operation of deleting elements, without using the unset function to delete, so short division is simpler and easier to understand.

2. High efficiency. Using short division, you can operate directly on the original array, reducing unnecessary operations, so it is more efficient than other methods.

3. Keep the original array. Using short division, you can actually retain the original array, but through the cutting operation, some elements of the original array are "invisible". For the needs of change operations, the original array can be retained.

4. Restrictions on the use of short division

The prerequisite for using short division is that the following two conditions must be met:

1. The subscript of the array is a non-negative integer. And non-consecutive subscripts. That is, the array is an indexed array and there is no deletion of duplicate elements.

2. It is applicable when the array is small. If the array is large, it is not recommended because copying the array will cause additional memory overhead and is not conducive to the performance of the program.

5. Summary

Short division is a very simple and efficient method of deleting array elements, and is suitable for small-scale array deletion operations. Using short division can retain the original array, save operation code, and improve program efficiency. Compared with using unset to delete elements, short division is more convenient and faster, and it is a trick well known to PHP programmers.

The above is the detailed content of php array short division. 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

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

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

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)

PHP 8 JIT (Just-In-Time) Compilation: How it improves performance. PHP 8 JIT (Just-In-Time) Compilation: How it improves performance. Mar 25, 2025 am 10:37 AM

PHP 8's JIT compilation enhances performance by compiling frequently executed code into machine code, benefiting applications with heavy computations and reducing execution times.

OWASP Top 10 PHP: Describe and mitigate common vulnerabilities. OWASP Top 10 PHP: Describe and mitigate common vulnerabilities. Mar 26, 2025 pm 04:13 PM

The article discusses OWASP Top 10 vulnerabilities in PHP and mitigation strategies. Key issues include injection, broken authentication, and XSS, with recommended tools for monitoring and securing PHP applications.

PHP Secure File Uploads: Preventing file-related vulnerabilities. PHP Secure File Uploads: Preventing file-related vulnerabilities. Mar 26, 2025 pm 04:18 PM

The article discusses securing PHP file uploads to prevent vulnerabilities like code injection. It focuses on file type validation, secure storage, and error handling to enhance application security.

PHP Encryption: Symmetric vs. asymmetric encryption. PHP Encryption: Symmetric vs. asymmetric encryption. Mar 25, 2025 pm 03:12 PM

The article discusses symmetric and asymmetric encryption in PHP, comparing their suitability, performance, and security differences. Symmetric encryption is faster and suited for bulk data, while asymmetric is used for secure key exchange.

PHP Authentication & Authorization: Secure implementation. PHP Authentication & Authorization: Secure implementation. Mar 25, 2025 pm 03:06 PM

The article discusses implementing robust authentication and authorization in PHP to prevent unauthorized access, detailing best practices and recommending security-enhancing tools.

How do you retrieve data from a database using PHP? How do you retrieve data from a database using PHP? Mar 20, 2025 pm 04:57 PM

Article discusses retrieving data from databases using PHP, covering steps, security measures, optimization techniques, and common errors with solutions.Character count: 159

PHP CSRF Protection: How to prevent CSRF attacks. PHP CSRF Protection: How to prevent CSRF attacks. Mar 25, 2025 pm 03:05 PM

The article discusses strategies to prevent CSRF attacks in PHP, including using CSRF tokens, Same-Site cookies, and proper session management.

What is the purpose of mysqli_query() and mysqli_fetch_assoc()? What is the purpose of mysqli_query() and mysqli_fetch_assoc()? Mar 20, 2025 pm 04:55 PM

The article discusses the mysqli_query() and mysqli_fetch_assoc() functions in PHP for MySQL database interactions. It explains their roles, differences, and provides a practical example of their use. The main argument focuses on the benefits of usin

See all articles