PHP随机图像集

Question

I'm using a php script to randomly show images. I've duplicated this script three times because I wanted to show three random images at once - I'm unsure of how to change the php code to show 3 images.

The problem is, I don't want to run into the chance of all three scripts showing the same images at once. Is there something that I could add to this code to make sure that each image displayed is always different?

<?php 
$random = "random.txt"; 
$fp = file($random); 
srand((double)microtime()*1000000); 
$rl = $fp[array_rand($fp)]; 
echo $rl; 
?>

the html:

 <?php include("rotate.php"); ?>
 <?php include("rotate.php"); ?>
 <?php include("rotate.php"); ?>

*the random.txt just has a list of filenames with links.

Answer 1

You can use array_rand() to select more than one random key at a time, like this:

$random = "random.txt";
$fp = file($random);
shuffle($fp);
// You don't need this. The array_rand() function
// is automatically seeded as of 4.2.0
// srand((double)microtime()*1000000);
$keys = array_rand($fp, 3);
for ($i = 0; $i < 3; $i++):
    $rl = $fp[$keys[$i]]; 
    echo $rl;
endfor;

This would eliminate the need for including the file multiple times. It can all be done at once.