<?php
//必须通过超级连接进入才有输出
Echo $_SERVER['HTTP_REFERER'];
?>

<?php
//入库时
$str=addslashes($str);
$sql="insert into `tab` (`content`) values('$str')";
//出库时
$str=stripslashes($str);
//显示时
$str=htmlspecialchars(nl2br($str)) ;
?>

<?php 
$s="http://{$_SERVER['HTTP_HOST']}:{$_SERVER["SERVER_PORT"]}{$_SERVER['script_NAME']}"; 
$se=''; 
foreach ($_GET as $key => $value) { 
$se.=$key."=".$value."&"; 
} 
$se=Preg_Replace("/(.*)&$/","$1",$se); 
$se?$se="?".$se:"";
echo $s."?$se"; 
?>

<?php 
session_cache_limiter('private, must-revalidate');
session_start(); 
...........
..........
?>

<?
Header("Content-type: image/png");
$img = ImageCreate(180,50);
$ip = $_SERVER['REMOTE_ADDR'];
ImageColorTransparent($img,$bgcolor);
$bgColor = ImageColorAllocate($img, 0x2c,0x6D,0xAF); // 背景颜色
$shadow = ImageColorAllocate($img, 250,0,0); // 阴影颜色
$textColor = ImageColorAllocate($img, oxff,oxff,oxff); // 字体颜色
ImageTTFText($img,10,0,78,30,$shadow,"d:/windows/fonts/Tahoma.ttf",$ip); //显示背景
ImageTTFText($img,10,0,25,28,$textColor,"d:/windows/fonts/Tahoma.ttf","your ip is".$ip); // 显示IP
ImagePng($img);
imagecreatefrompng($img);
ImageDestroy($img);
?>