使用 PHP 读取文件 - fopen/fread

<?php

$top = "../top.txt";
$middle = "../middle.txt";
$bottom = "../bottom.txt";
$end = "/st.txt";
$data = "/dt.txt";

$handle1 = fopen($top, "r"); 
$contents1 = fread($handle1, filesize($top)); 
fclose($handle1); 

$handle2 = fopen($end, "r"); 
$contents2 = fread($handle2, filesize($end)); 
fclose($handle2);

$handle3 = fopen($middle, "r"); 
$contents3 = fread($handle3, filesize($middle)); 
fclose($handle3);

$handle4 = fopen($data, "r"); 
$contents4 = fread($handle4, filesize($data)); 
fclose($handle4);

$handle5 = fopen($bottom, "r"); 
$contents5 = fread($handle5, filesize($bottom)); 
fclose($handle5);

echo $contents1;
echo $contents2;
echo $contents3;
echo $contents4;
echo $contents5;

?>

我对其中每一个都收到以下错误：

警告：fopen（../top.txt）[function.fopen]：无法打开流：没有这样的文件或目录

警告：filesize() [function.filesize]：../top.txt 统计失败

警告：fread()：提供的参数不是有效的流资源

警告：fclose()：提供的参数不是有效的流资源

所有文件和文件夹中的 CHMOD 并设置为 777

所有文件都存在于服务器上

服务器上安装了PHP5

我究竟做错了什么？

使用整个路径，而不是../top.txt use /path/to/top.txt

OR

你也用$top = $_SERVER['DOCUMENT_ROOT'] . "/../top.txt";