search
HomeBackend DevelopmentPHP TutorialHow to generate thumbnails in php

How to generate thumbnails in php

Jun 08, 2018 am 11:54 AM
phpgenerate

本篇文章主要介绍php生成缩略图的方法,感兴趣的朋友参考下,希望对大家有所帮助。

PHP上传图片、生成缩略图是比较常用到的功能,一般我们会把这些功能写一个类,方便我们调用。今天发现了一个比较简单些的PHP生成缩略图函数的代码,不敢独享,特此与大家分享。自己使用时候认真看一下,代码中都有注释的。

本文实例讲述了PHP简单生成缩略图相册的方法。具体如下:

<?php
/*
 * written by mot
 * 根目录下自己新建image thumb目录
 * */
class thumb{
  private $src;
  private $source;
  private $s_width;
  private $s_height;
  private $dest;
  private $d_height;
  private $d_width;
  private $name;
  public function thumb($image_path,$rate = 0.5){
    $this->src = $image_path;
    $this->source = imagecreatefromjpeg($image_path);
    $s_size = getimagesize($image_path);
    $this->s_height = $s_size[1];
    $this->s_width = $s_size[0];
    $this->d_height = 100;
    $this->d_width = 100;
    $this->dest = imagecreate($this->d_width, $this->d_height);
    $this->name = explode(&#39;.jpg&#39;, $image_path);
    $this->name = $this->name[0];
  }
  public function make(){
    imagecopyresized($this->dest, $this->source, 0, 0, 0, 0, $this->d_width, $this->d_height,
    $this->s_width, $this->s_height);
    $thumb = str_replace(&#39;image&#39;, &#39;thumb&#39;, $this->name.&#39;-thumb.jpg&#39;);
    imagejpeg($this->dest,$thumb,100);
    $img = $thumb;
    echo "<a href=$this->src><img  src=$img alt="How to generate thumbnails in php" ></a>";
  }
}
$hl = opendir(".\\image\\");
while(false != $file = readdir($hl)){
  if($file == &#39;.&#39; || $file == &#39;..&#39;) continue;
  $path = &#39;.\\image\\&#39;.$file;
  $tmp = new thumb($path,0.3);
  $tmp->make();
}

总结:以上就是本篇文的全部内容,希望能对大家的学习有所帮助。

相关推荐:

php可逆加密的方法及原理

PHP处理会话的10个函数

PHP如何获得微信公众平台关注用户的基本信息

The above is the detailed content of How to generate thumbnails in php. For more information, please follow other related articles on the PHP Chinese website!

Statement
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
How do you modify data stored in a PHP session?How do you modify data stored in a PHP session?Apr 27, 2025 am 12:23 AM

TomodifydatainaPHPsession,startthesessionwithsession_start(),thenuse$_SESSIONtoset,modify,orremovevariables.1)Startthesession.2)Setormodifysessionvariablesusing$_SESSION.3)Removevariableswithunset().4)Clearallvariableswithsession_unset().5)Destroythe

Give an example of storing an array in a PHP session.Give an example of storing an array in a PHP session.Apr 27, 2025 am 12:20 AM

Arrays can be stored in PHP sessions. 1. Start the session and use session_start(). 2. Create an array and store it in $_SESSION. 3. Retrieve the array through $_SESSION. 4. Optimize session data to improve performance.

How does garbage collection work for PHP sessions?How does garbage collection work for PHP sessions?Apr 27, 2025 am 12:19 AM

PHP session garbage collection is triggered through a probability mechanism to clean up expired session data. 1) Set the trigger probability and session life cycle in the configuration file; 2) You can use cron tasks to optimize high-load applications; 3) You need to balance the garbage collection frequency and performance to avoid data loss.

How can you trace session activity in PHP?How can you trace session activity in PHP?Apr 27, 2025 am 12:10 AM

Tracking user session activities in PHP is implemented through session management. 1) Use session_start() to start the session. 2) Store and access data through the $_SESSION array. 3) Call session_destroy() to end the session. Session tracking is used for user behavior analysis, security monitoring, and performance optimization.

How can you use a database to store PHP session data?How can you use a database to store PHP session data?Apr 27, 2025 am 12:02 AM

Using databases to store PHP session data can improve performance and scalability. 1) Configure MySQL to store session data: Set up the session processor in php.ini or PHP code. 2) Implement custom session processor: define open, close, read, write and other functions to interact with the database. 3) Optimization and best practices: Use indexing, caching, data compression and distributed storage to improve performance.

Explain the concept of a PHP session in simple terms.Explain the concept of a PHP session in simple terms.Apr 26, 2025 am 12:09 AM

PHPsessionstrackuserdataacrossmultiplepagerequestsusingauniqueIDstoredinacookie.Here'showtomanagethemeffectively:1)Startasessionwithsession_start()andstoredatain$_SESSION.2)RegeneratethesessionIDafterloginwithsession_regenerate_id(true)topreventsessi

How do you loop through all the values stored in a PHP session?How do you loop through all the values stored in a PHP session?Apr 26, 2025 am 12:06 AM

In PHP, iterating through session data can be achieved through the following steps: 1. Start the session using session_start(). 2. Iterate through foreach loop through all key-value pairs in the $_SESSION array. 3. When processing complex data structures, use is_array() or is_object() functions and use print_r() to output detailed information. 4. When optimizing traversal, paging can be used to avoid processing large amounts of data at one time. This will help you manage and use PHP session data more efficiently in your actual project.

Explain how to use sessions for user authentication.Explain how to use sessions for user authentication.Apr 26, 2025 am 12:04 AM

The session realizes user authentication through the server-side state management mechanism. 1) Session creation and generation of unique IDs, 2) IDs are passed through cookies, 3) Server stores and accesses session data through IDs, 4) User authentication and status management are realized, improving application security and user experience.

See all articles

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

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

SecLists

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.