Table of Contents
PHP SPL标准库之SplFixedArray使用实例,splsplfixedarray
Home php教程 php手册 PHP SPL标准库之SplFixedArray使用实例,splsplfixedarray

PHP SPL标准库之SplFixedArray使用实例,splsplfixedarray

Jun 13, 2016 am 09:04 AM
php

PHP SPL标准库之SplFixedArray使用实例,splsplfixedarray

SplFixedArray主要是处理数组相关的主要功能,与普通php array不同的是,它是固定长度的,且以数字为键名的数组,优势就是比普通的数组处理更快。

看看我本机的Benchmark测试:

ini_set('memory_limit','12800M');
 
for($size = 10000; $size < 10000000; $size *= 4) {
  echo PHP_EOL . "Testing size: $size" . PHP_EOL;
  for($s = microtime(true), $container = Array(), $i = 0; $i < $size; $i++) $container[$i] = NULL;
  echo "Array(): " . (microtime(true) - $s) . PHP_EOL;
 
  for($s = microtime(true), $container = new SplFixedArray($size), $i = 0; $i < $size; $i++) $container[$i] = NULL;
  echo "SplArray(): " . (microtime(true) - $s) . PHP_EOL;
}
Copy after login

结果如下:

Testing size: 10000
Array(): 0.004000186920166
SplArray(): 0.0019998550415039
 
Testing size: 40000
Array(): 0.017001152038574
SplArray(): 0.0090007781982422
 
Testing size: 160000
Array(): 0.050002098083496
SplArray(): 0.046003103256226
 
Testing size: 640000
Array(): 0.19701099395752
SplArray(): 0.16700983047485
 
Testing size: 2560000
Array(): 0.75704312324524
SplArray(): 0.67303895950317

Copy after login

通常情况下SplFixedArray要比php array快上20%~30%,所以如果你是处理巨大数量的固定长度数组,还是强烈建议使用。
SplFixedArray类摘要如下:

SplFixedArray implements Iterator  , ArrayAccess  , Countable  {
  /* 方法 */
  public __construct ([ int $size = 0 ] )
  public int count ( void )
  public mixed current ( void )
  public static SplFixedArray fromArray ( array $array [, bool $save_indexes = true ] )
  public int getSize ( void )
  public int key ( void )
  public void next ( void )
  public bool offsetExists ( int $index )
  public mixed offsetGet ( int $index )
  public void offsetSet ( int $index , mixed $newval )
  public void offsetUnset ( int $index )
  public void rewind ( void )
  public int setSize ( int $size )
  public array toArray ( void )
  public bool valid ( void )
  public void __wakeup ( void )
}

Copy after login

使用SplFixedArray:

$arr = new SplFixedArray(4);
$arr[0] = 'php';
$arr[1] = 1;
$arr[3] = 'python';
 
//遍历, $arr[2] 为null
foreach($arr as $v) {
  echo $v . PHP_EOL;
}
 
//获取数组长度
echo $arr->getSize(); //4
 
//增加数组长度
$arr->setSize(5);
$arr[4] = 'new one';
 
//捕获异常
try{
  echo $arr[10];
} catch (RuntimeException $e) {
  echo $e->getMessage();
} 
Copy after login

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 Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Repo: How To Revive Teammates
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

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)

CakePHP Project Configuration CakePHP Project Configuration Sep 10, 2024 pm 05:25 PM

In this chapter, we will understand the Environment Variables, General Configuration, Database Configuration and Email Configuration in CakePHP.

PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian Dec 24, 2024 pm 04:42 PM

PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati

CakePHP Date and Time CakePHP Date and Time Sep 10, 2024 pm 05:27 PM

To work with date and time in cakephp4, we are going to make use of the available FrozenTime class.

CakePHP File upload CakePHP File upload Sep 10, 2024 pm 05:27 PM

To work on file upload we are going to use the form helper. Here, is an example for file upload.

CakePHP Routing CakePHP Routing Sep 10, 2024 pm 05:25 PM

In this chapter, we are going to learn the following topics related to routing ?

Discuss CakePHP Discuss CakePHP Sep 10, 2024 pm 05:28 PM

CakePHP is an open-source framework for PHP. It is intended to make developing, deploying and maintaining applications much easier. CakePHP is based on a MVC-like architecture that is both powerful and easy to grasp. Models, Views, and Controllers gu

How To Set Up Visual Studio Code (VS Code) for PHP Development How To Set Up Visual Studio Code (VS Code) for PHP Development Dec 20, 2024 am 11:31 AM

Visual Studio Code, also known as VS Code, is a free source code editor — or integrated development environment (IDE) — available for all major operating systems. With a large collection of extensions for many programming languages, VS Code can be c

CakePHP Creating Validators CakePHP Creating Validators Sep 10, 2024 pm 05:26 PM

Validator can be created by adding the following two lines in the controller.

See all articles