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HomeBackend DevelopmentPHP Tutorialphp infinite directory traversal

使用的函数有:

isset()判断某个变量是否定义

chdir() 将当前目录改变为指定的目录。

opendir() 打开目录。

readdir()读取目录。

getcwd()。获取当前目录。

还用到了for  if  GET传值 大概就这些东东:

下面是代码:

<?php if(isset($_GET['id']))//判断是否传值
{
    $s=str_replace(' ','+',$_GET['id']);
    $s=base64_decode($s);//接受传递的值 值一般是要打开的目录的绝对路劲
        chdir($s);//切换到要打开的目录
    }
$a=opendir('.');//打开当前目录
while(false!==($c=readdir($a)))//循环遍历目录内容的文件名
{         
       if(is_dir($c))//判断是目录还是文件
       {
           if($c=='.')
           {
               }
               else
               {
           if($c=='..')
           {
           $w=base64_encode(substr(getcwd(),0,strrpos(getcwd(),'\\')));//当前路径加上目录名 就是目录的绝对路径
           echo "上一级"."<a href='6.php?id=$w'>打开<br>";//当点击打开时将要打开的绝对路径传递出去  用chdir 切换到要打开的目录下
           }else
           {
               $w=base64_encode(getcwd().'\\'.$c);//当前路径加上目录名 就是目录的绝对路径
           echo "$c"."<a href="6.php?id=%24w">打开</a><br>";//当点击打开时将要打开的绝对路径传递出去  用chdir 切换到要打开的目录下
               }
               }
           }
           else
           {
               echo "$c 不是目录<br>";
               }
}

?>

以上就介绍了php无限遍历目录,包括了方面的内容,希望对PHP教程有兴趣的朋友有所帮助。

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