Home > Article > Backend Development > Summary of methods for randomly displaying images in PHP, _PHP tutorial

Summary of methods for randomly displaying images in PHP, _PHP tutorial

WBOYOriginal: 2016-07-13 09:53:08782browse

A summary of how to randomly display images in php.

php generates random numbers through the rand() function. This function can generate a number within a specified range

This code randomly selects pictures by generating random numbers

<html>
<body>
<&#63;php
 srand( microtime() * 1000000 );
 $num = rand( 1, 4 );
  
 switch( $num )
 {
 case 1: $image_file = "/home/images/alfa.jpg";
     break;
 case 2: $image_file = "/home/images/ferrari.jpg";
     break;
 case 3: $image_file = "/home/images/jaguar.jpg";
     break;
 case 4: $image_file = "/home/images/porsche.jpg";
     break;
 }
 echo "Random Image : <img src=$image_file />";
&#63;>
</body>
</html>

Method 2:

<&#63;
$handle = opendir('./'); //当前目录
while (false !== ($file = readdir($handle))) { //遍历该php教程文件所在目录
list($filesname,$kzm)=explode(".",$file);//获取扩展名
if ($kzm=="gif" or $kzm=="jpg") { //文件过滤
if (!is_dir('./'.$file)) { //文件夹过滤
$array[]=$file;//把符合条件的文件名存入数组
}
}
}
$suiji=array_rand($array); //使用array_rand函数从数组中随机抽出一个单元
&#63;>
<img src="<&#63;=$array[$suiji]&#63;>">

Method 3:

<&#63;php
/**********************************************
* Filename : img.php
* Author : freemouse
* Usage:
* <img src=img.php>
* <img src=img.php&#63;folder=images2/>
***********************************************/
if($_GET['folder']){
$folder=$_GET['folder'];
}else{
$folder='/images/';
}
//存放图片文件的位置
$path = $_SERVER['DOCUMENT_ROOT']."/".$folder;
$files=array();
if ($handle=opendir("$path")) {
while(false !== ($file = readdir($handle))) {
if ($file != "." && $file != "..") {
if(substr($file,-3)=='gif' || substr($file,-3)=='jpg') $files[count($files)] = $file;
}
}
}
closedir($handle);
$random=rand(0,count($files)-1);
if(substr($files[$random],-3)=='gif') header("Content-type: image/gif");
elseif(substr($files[$random],-3)=='jpg') header("Content-type: image/jpeg");
readfile("$path/$files[$random]");
&#63;>

The above is the entire content of this article, I hope you all like it.

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

Previous article：PHP dynamic function calling method, PHP dynamic calling_PHP tutorialNext article：PHP dynamic function calling method, PHP dynamic calling_PHP tutorial

See more

Summary of methods for randomly displaying images in PHP, _PHP tutorial

A summary of how to randomly display images in php.

Related articles