如何实现网站根据ip判断地区 自动跳转到所属地区页面【PHP版】

<?php

//返回当前IP的城市字符串

function convertip($ip) {

//IP数据文件路径

$dat_path = 'QQWry.Dat';

//检查IP地址

if(!preg_match("/^(/d{1,2}|1/d/d|2[0-4]/d|25[0-5])/.(/d{1,2}|1/d/d|2[0-4]/d|25[0-5])/.(/d{1,2}|1/d/d|2[0-4]/d|25[0-5])/.(/d{1,2}|1/d/d|2[0-4]/d|25[0-5])$/",
$ip)) {

return 'IP Address Error';

}

//打开IP数据文件

if(!$fd = @fopen($dat_path, 'rb')){

return 'IP date file not exists or access denied';

}

//分解IP进行运算，得出整形数

$ip = explode('.', $ip);

$ipNum = $ip[0] * 16777216 + $ip[1] * 65536 + $ip[2] * 256 +
$ip[3];

//获取IP数据索引开始和结束位置

$DataBegin = fread($fd, 4);

$DataEnd = fread($fd, 4);

$ipbegin = implode('', unpack('L', $DataBegin));

if($ipbegin < 0) $ipbegin += pow(2, 32);

$ipend = implode('', unpack('L', $DataEnd));

if($ipend < 0) $ipend += pow(2, 32);

$ipAllNum = ($ipend - $ipbegin) / 7 + 1;

$BeginNum = 0;

$EndNum = $ipAllNum;

//使用二分查找法从索引记录中搜索匹配的IP记录

while($ip1num>$ipNum || $ip2num<$ipNum) {

$Middle= intval(($EndNum + $BeginNum) / 2);

//偏移指针到索引位置读取4个字节

fseek($fd, $ipbegin + 7 * $Middle);

$ipData1 = fread($fd, 4);

if(strlen($ipData1) < 4) {

fclose($fd);

return 'System Error';

}

//提取出来的数据转换成长整形，如果数据是负数则加上2的32次幂

$ip1num = implode('', unpack('L', $ipData1));

if($ip1num < 0) $ip1num += pow(2, 32);

//提取的长整型数大于我们IP地址则修改结束位置进行下一次循环

if($ip1num > $ipNum) {

$EndNum = $Middle;

continue;

}

//取完上一个索引后取下一个索引

$DataSeek = fread($fd, 3);

if(strlen($DataSeek) < 3) {

fclose($fd);

return 'System Error';

}

$DataSeek = implode('', unpack('L', $DataSeek.chr(0)));

fseek($fd, $DataSeek);

$ipData2 = fread($fd, 4);

if(strlen($ipData2) < 4) {

fclose($fd);

return 'System Error';

}

$ip2num = implode('', unpack('L', $ipData2));

if($ip2num < 0) $ip2num += pow(2, 32);

//没找到提示未知

if($ip2num < $ipNum) {

if($Middle == $BeginNum) {

fclose($fd);

return 'Unknown';

}

$BeginNum = $Middle;

}

}

$ipFlag = fread($fd, 1);

if($ipFlag == chr(1)) {

$ipSeek = fread($fd, 3);

if(strlen($ipSeek) < 3) {

fclose($fd);

return 'System Error';

}

$ipSeek = implode('', unpack('L', $ipSeek.chr(0)));

fseek($fd, $ipSeek);

$ipFlag = fread($fd, 1);

}

if($ipFlag == chr(2)) {

$AddrSeek = fread($fd, 3);

if(strlen($AddrSeek) < 3) {

fclose($fd);

return 'System Error';

}

$ipFlag = fread($fd, 1);

if($ipFlag == chr(2)) {

$AddrSeek2 = fread($fd, 3);

if(strlen($AddrSeek2) < 3) {

fclose($fd);

return 'System Error';

}

$AddrSeek2 = implode('', unpack('L', $AddrSeek2.chr(0)));

fseek($fd, $AddrSeek2);

} else {

fseek($fd, -1, SEEK_CUR);

}

while(($char = fread($fd, 1)) != chr(0))

$ipAddr2 .= $char;

$AddrSeek = implode('', unpack('L', $AddrSeek.chr(0)));

fseek($fd, $AddrSeek);

while(($char = fread($fd, 1)) != chr(0))

$ipAddr1 .= $char;

} else {

fseek($fd, -1, SEEK_CUR);

while(($char = fread($fd, 1)) != chr(0))

$ipAddr1 .= $char;

$ipFlag = fread($fd, 1);

if($ipFlag == chr(2)) {

$AddrSeek2 = fread($fd, 3);

if(strlen($AddrSeek2) < 3) {

fclose($fd);

return 'System Error';

}

$AddrSeek2 = implode('', unpack('L', $AddrSeek2.chr(0)));

fseek($fd, $AddrSeek2);

} else {

fseek($fd, -1, SEEK_CUR);

}

while(($char = fread($fd, 1)) != chr(0)){

$ipAddr2 .= $char;

}

}

fclose($fd);

//最后做相应的替换操作后返回结果

if(preg_match('/http/i', $ipAddr2)) {

$ipAddr2 = '';

}

$ipaddr = "$ipAddr1 $ipAddr2";

$ipaddr = preg_replace('/CZ88.Net/is', '', $ipaddr);

$ipaddr = preg_replace('/^s*/is', '', $ipaddr);

$ipaddr = preg_replace('/s*$/is', '', $ipaddr);

if(preg_match('/http/i', $ipaddr) || $ipaddr == '') {

$ipaddr = 'Unknown';

}

return $ipaddr;

}

//查找字符串

function findstr($str, $substr)

{

$m = strlen($str);

$n = strlen($substr );

if ($m < $n) return false ;

for ($i=0; $i <=($m-$n+1); $i ++){

$sub = substr( $str, $i, $n);

if ( strcmp($sub, $substr) == 0) return true;

}

return false ;

}

?>

<?php

$Clientip=$_SERVER["REMOTE_ADDR"];

$ClientSity=convertip($Clientip);

if (findstr($ClientSity,"北京")){

//out.print("beijing");

Header("Location: http://www.qq.com
");

}else{

//out.print("false beijing");

Header("Location: http://www.163.com
");

}

?>