<?php
include_once('./qqwry.php');
$qqwry=new qqwry;
function get_real_ip(){
$ip=false;
if(!empty($_server["http_client_ip"])){
$ip = $_server["http_client_ip"];
}
if (!empty($_server['http_x_forwarded_for'])) {
$ips = explode (", ", $_server['http_x_forwarded_for']);
if ($ip) { array_unshift($ips, $ip); $ip = false; }
for ($i = 0; $i < count($ips); $i++) {
if (!eregi ("^(10|172\.16|192\.168)\.", $ips[$i])) {
$ip = $ips[$i];
break;
}
}
}
return $ip;
}
function is_ip($str) {
$ip = explode(".", $str);
if (count($ip)<4 || count($ip)>4) return 0;
foreach($ip as $ip_addr) {
if ( !is_numeric($ip_addr) ) return 0;
if ( $ip_addr<0 || $ip_addr>255 ) return 0;
}
return 1;
}
$ip=$_server['remote_addr'];
$iferr=$qqwry->qqwry($ip);
$city = $qqwry->country.$qqwry->local;
//echo $city;*/
if (strpos($city,'玄武区')!==false){
$city = "玄武区";
}
else if(strpos($city,'仙林')!==false){
$city = "仙林";
}
else if(strpos($city,'秦淮区')!==false){
$city = "秦淮区";
}
else if(strpos($city,'江宁')!==false){
$city = "江宁";
}
else if(strpos($city,'鼓楼')!==false){
$city = "鼓楼";
}
else{
$city = "栖霞";
}
if (isset($_get['chengshi'])) { //ê×ïè¼ì²âêç·ñ»ñµãáë get ´«µýµäêý¾ý
setcookie("cookie_city",$_get['chengshi'],time()+3600*24);
$city = $_get['chengshi'];
}
else if (isset($_cookie["cookie_city"])) { //¼ì²âêç·ñ´æôúêç³æcookie
$city = $_cookie["cookie_city"]; //ïôê¾cookie±£´æµäêý¾ý
}
else {
setcookie("cookie_city",$city,time()+3600*24); //´¿³õê¼»¯´ë±äá¿
$_cookie["cookie_city"] = $city;
}
?>
使用方法：解压后qqwry.dat就是我们想要ip地址数据库，我们新建一个ipcity文件夹，将数据库放在下面。qq ip数据库使用非常方便，数据也很齐全，你可以及时关注官方更新以保持数据最新，强力推荐一下：）
<?
/*
函数名称：ipcity
参数说明：$userip——用户ip地址
函数功能：php通过ip地址判断用户所在城市
author:lee
contact:xpsem2010@gmail.com
*/
function ipcity($userip) {
//ip数据库路径，这里用的是qq ip数据库 20110405 纯真版
$dat_path = 'qqwry.dat';
//判断ip地址是否有效
if(!ereg("^([0-9]{1,3}.){3}[0-9]{1,3}$", $userip)){
return 'ip address invalid';
}
//打开ip数据库
if(!$fd = @fopen($dat_path, 'rb')){
return 'ip data file not exists or access denied';
}
//explode函数分解ip地址，运算得出整数形结果
$userip = explode('.', $userip);
$useripnum = $userip[0] * 16777216 + $userip[1] * 65536 + $userip[2] * 256 + $userip[3];
//获取ip地址索引开始和结束位置
$databegin = fread($fd, 4);
$dataend = fread($fd, 4);
$useripbegin = implode('', unpack('l', $databegin));
if($useripbegin < 0) $useripbegin += pow(2, 32);
$useripend = implode('', unpack('l', $dataend));
if($useripend < 0) $useripend += pow(2, 32);
$useripallnum = ($useripend - $useripbegin) / 7 + 1;
$beginnum = 0;
$endnum = $useripallnum;
//使用二分查找法从索引记录中搜索匹配的ip地址记录
while($userip1num>$useripnum || $userip2num<$useripnum) {
$middle= intval(($endnum + $beginnum) / 2);
//偏移指针到索引位置读取4个字节
fseek($fd, $useripbegin + 7 * $middle);
$useripdata1 = fread($fd, 4);
if(strlen($useripdata1) < 4) {
fclose($fd);
return 'file 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
$userip1num = implode('', unpack('l', $useripdata1));
if($userip1num < 0) $userip1num += pow(2, 32);
//提取的长整型数大于我们ip地址则修改结束位置进行下一次循环
if($userip1num > $useripnum) {
$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 'file error';
}
$dataseek = implode('', unpack('l', $dataseek.chr(0)));
fseek($fd, $dataseek);
$useripdata2 = fread($fd, 4);
if(strlen($useripdata2) < 4) {
fclose($fd);
return 'file error';
}
$userip2num = implode('', unpack('l', $useripdata2));
if($userip2num < 0) $userip2num += pow(2, 32);
//找不到ip地址对应城市
if($userip2num < $useripnum) {
if($middle == $beginnum) {
fclose($fd);
return 'no data';
}
$beginnum = $middle;
}
}
$useripflag = fread($fd, 1);
if($useripflag == chr(1)) {
$useripseek = fread($fd, 3);
if(strlen($useripseek) < 3) {
fclose($fd);
return 'system error';
}
$useripseek = implode('', unpack('l', $useripseek.chr(0)));
fseek($fd, $useripseek);
$useripflag = fread($fd, 1);
}
if($useripflag == chr(2)) {
$addrseek = fread($fd, 3);
if(strlen($addrseek) < 3) {
fclose($fd);
return 'system error';
}
$useripflag = fread($fd, 1);
if($useripflag == 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))
$useripaddr2 .= $char;
$addrseek = implode('', unpack('l', $addrseek.chr(0)));
fseek($fd, $addrseek);
while(($char = fread($fd, 1)) != chr(0))
$useripaddr1 .= $char;
} else {
fseek($fd, -1, seek_cur);
while(($char = fread($fd, 1)) != chr(0))
$useripaddr1 .= $char;
$useripflag = fread($fd, 1);
if($useripflag == 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)){
$useripaddr2 .= $char;
}
}
fclose($fd);
//返回ip地址对应的城市结果
if(preg_match('/http/i', $useripaddr2)) {
$useripaddr2 = '';
}
$useripaddr = "$useripaddr1 $useripaddr2";
$useripaddr = preg_replace('/cz88.net/is', '', $useripaddr);
$useripaddr = preg_replace('/^s*/is', '', $useripaddr);
$useripaddr = preg_replace('/s*$/is', '', $useripaddr);
if(preg_match('/http/i', $useripaddr) || $useripaddr == '') {
$useripaddr = 'no data';
}
return $useripaddr;
}
?>
<script src="/ipcity/ipaddress.php" type="text/javascript" language="javascript"></script>
以上就是php获取ip地址、php根据ip地址判断城市以及php根据ip地址实现城市切换或跳转的详细介绍了，事实上，像php中通过ip地址自动切换城市就是这个方法的典型应用。举一反三，我们通过这种方法，也可以实现屏蔽指定ip地址或城市的用户访问，自己研究一下吧，也挺简单的：）
