php如何禁止ip访问

<?php include("banIP.php");?>

<?php 
//禁用ip地址 
$ip=$_SERVER["REMOTE_ADDR"]; 
$ban=file_get_contents("ban.dat"); 
if(stripos($ban,$ip)) 
{ 
  die("Your IP Address is:$ip,you&#39;re forbiden to view this page!");   
} 
echo "Your IP Address is:$ip,hello!"; 
?>

ban.dat文件如下:
BEGIN: 
119.184.251.245 
127.0.0.1 
192.168.1.100
禁用ip段如下：
<?php 
//禁用ip地址 
$ip=$_SERVER["REMOTE_ADDR"]; 
while($ip[count($ip-1)]!=&#39;.&#39;)$ip=substr($ip,1, -1); //整理出ip段 
$ban=file_get_contents("ban.dat"); 
if(stripos($ban,$ip)) 
{ 
  die("U&#39;re forbiden to view this page!");   
} 
echo "Hello!"; 
?>