PHP随机显示图片

PHP随机显示图片

<html>
   <body>

      <?php
         srand( microtime() * 1000000 );
         $num = rand( 1, 4 );

         switch( $num ) {
            case 1: $image_file = "/php/images/logo.png";
               break;

            case 2: $image_file = "/php/images/php.jpg";
               break;

            case 3: $image_file = "/php/images/logo.png";
               break;

            case 4: $image_file = "/php/images/php.jpg";
               break;
         }
         echo "Random Image : <img src=$image_file />";
      ?>

   </body>
</html>