Home Backend Development PHP Tutorial PHP program acceleration exploration cache output_PHP tutorial

PHP program acceleration exploration cache output_PHP tutorial

Jul 20, 2016 am 11:17 AM
cache pear php content accelerate start us explore use program cache output

Content cache output PEAR cache

Next we start to explore more commonly used caching technologies, which is also the focus of this article. First we use the cache package in PEAR. PEAR can cache content in files, databases or memory. Let's take files as an example.

The following is a PHP applet without caching:

pear_content_cache1.php

<?php
echo "This is the content.<P>";
echo "The current time is" . date('M-d-Y H:i:s A', time()) . "<BR>";
?>

The above program is very simple, now we add caching to it.

pear_content_cache2.php

<?php
require_once 'Cache/Output.php';

//Set the cache directory, which must be writable
$cacheDir = './pear_cache';
$cache = new Cache_Output('file',array('cache_dir' => $cacheDir));

//If the nocache variable is empty, use the content in the cache
//If you want to get the latest content, you need to assign it to the nocache variable
if (empty($_REQUEST['nocache']))
{
// Create a unique cache identifier
// Request + Cookie information
$cache_id = $cache->generateID(array('url' => $_REQUEST,'post' =>$_POST,'cookies' => $HTTP_COOKIE_VARS));
}
else
{
//If you want to get the latest content, the ID is empty
$cache_id = null;
}

// Check whether the cache content corresponding to the cache ID is available
if ($content = $cache->start($cache_id))
{
//The cache already exists, output directly, and end the script
echo $content;
exit();
}

// The content does not exist in the cache, generate new content and write it to the cache
echo "This is the content.<P>";
echo "The current time is" . date('M-d-Y H:i:s A', time()) . "<BR>";

// Write content to cache
echo $cache->end();
?>

Refresh these two files respectively, and you will find that the time in the line "The current time is" in pear_content_cache1.php changes with the refresh, while this line in pear_content_cache2.php does not change. This is because pear_content_cache2.php uses caching to store the content requested by the user in a static file. When the user requests again, it is output directly from the file without the need for a program to dynamically generate the content.

For pear_content_cache2.php, if the user wants to read the latest information instead of the old information in the cache. Then you can use http://…/pear_content_cache2.php?nocache=1 to access it, which will disable the caching function. Refresh it and see that the time will change accordingly.

Summary of the use of PEAR content caching class:

 1. When including the PEAR package, be sure to set the correct path.

2. Contains the cache class in Output.php

require_once 'Cache/Output.php';

 3. Set cache directory

$cacheDir = './pear_cache';

Confirm that this directory is writable. Cache data will be written to subdirectories of this directory.

 4. Create an output cache object

$cache = new Cache_Output('file',array('cache_dir' => $cacheDir));

The first parameter indicates that we use "file" based caching, and the second parameter is an array associated with the cache directory.

 5. Generate a unique cache ID

$cache_id = $cache->generateID(array('url' => $_REQUEST,'post' =>$_POST,'cookies' => $HTTP_COOKIE_VARS));

The generateID() method of the $cache object here provides an array of information (URL, HTTP POST data, and HTTP cookie) to uniquely identify this request and distinguish it from other requests.

 6. Add a logical judgment statement to see if the cache data corresponding to cacheID already exists. If it exists, obtain the data and end the script.

if ($content = $cache->start($cache_id))
{
echo $content;
exit();
}

 7. Place the code that generates content after the above logical statement and end using the cache object.

echo $cache->end();

Function cache output PEAR cache

In addition to caching the output content, PEAR can also cache the result of calling a certain function. This is a very interesting feature. If your program uses a certain function frequently and the result of the call is the same, I suggest you try it, especially if this function runs slowly.

Next we implement a buffered call to slowFunction(), a function that executes very slowly.

<?php
require_once 'Cache/Function.php';

$cacheDir = './pear_cache/';
$cache = new Cache_Function('file',array('cache_dir' => $cacheDir));
$arr = array('apple', 'pear', 'watermelon');
$cache->call('slowFunction', $arr);
echo '<BR>';

$arr = array('apple', 'pear', 'watermelon');
slowFunction($arr);

function slowFunction($arr = null)
{
echo "A function that executes very slowly:( <br>";
echo "The current time is " . date('M-d-Y H:i:s A', time()) . '<br>';
foreach ($arr as $fruit)
{
echo "I ate a $fruit <br>";
}
)
?>

The following is the script execution result of the example:

A function that executes very slowly

The current time is Jul-28-2004 17:15:57 PM
I ate an apple
I ate a pear
I ate a watermelon

A function that executes very slowly :(
The current time is Jul-28-2004 17:17:55 PM
I ate an apple
I ate a pear
I ate a watermelon

In the code, the Cache/Function.php class is used to perform the function buffering function. The $cache variable is a Cache_Function object that uses file-based function caching and is stored in the $cacheDir directory. To cache a function call, the call() method of the Cache_Function object $cache is used like this: $cache->call(‘slowFunction’, $arr);

Here, the slowFunction() function is called, and the parameter is an array $arr. This function is cached in a file in the $cacheDir directory. Any subsequent calls to this function will have the result of the function execution returned by $cache->call(). Function caching and usage are very similar to content caching, so I won’t go into details. Please check the PEAR manual for details.

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/372079.htmlTechArticleContent cache output PEAR cache Next we start to explore more commonly used caching technologies, which is also the focus of this article. First we use the cache package in PEAR. PEAR can cache content in...
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

Video Face Swap

Video Face Swap

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

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 8.4 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

7 PHP Functions I Regret I Didn't Know Before 7 PHP Functions I Regret I Didn't Know Before Nov 13, 2024 am 09:42 AM

If you are an experienced PHP developer, you might have the feeling that you’ve been there and done that already.You have developed a significant number of applications, debugged millions of lines of code, and tweaked a bunch of scripts to achieve op

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

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

PHP Program to Count Vowels in a String PHP Program to Count Vowels in a String Feb 07, 2025 pm 12:12 PM

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

How do you parse and process HTML/XML in PHP? How do you parse and process HTML/XML in PHP? Feb 07, 2025 am 11:57 AM

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

See all articles