根据IP地址的获取地理位置【原创】

时常会遇到根据用户的IP获取用户所在的城市，如“欢迎来自北京的张三”。所以有了下面的程序。

<?php
/*
 * 获取用户的IP地址
 */
header("Content-Type: text/plain;charset=gb2312");

function get_online_ip($format = 0) {
	
	if (getenv ( 'HTTP_CLIENT_IP' ) && strcasecmp ( getenv ( 'HTTP_CLIENT_IP' ), 'unknown' )) {
		$onlineip = getenv ( 'HTTP_CLIENT_IP' );
	} elseif (getenv ( 'HTTP_X_FORWARDED_FOR' ) && strcasecmp ( getenv ( 'HTTP_X_FORWARDED_FOR' ), 'unknown' )) {
		$onlineip = getenv ( 'HTTP_X_FORWARDED_FOR' );
	} elseif (getenv ( 'REMOTE_ADDR' ) && strcasecmp ( getenv ( 'REMOTE_ADDR' ), 'unknown' )) {
		$onlineip = getenv ( 'REMOTE_ADDR' );
	} elseif (isset ( $_SERVER ['REMOTE_ADDR'] ) && $_SERVER ['REMOTE_ADDR'] && strcasecmp ( $_SERVER ['REMOTE_ADDR'], 'unknown' )) {
		$onlineip = $_SERVER ['REMOTE_ADDR'];
	}
	preg_match ( "/[\d\.]{7,15}/", $onlineip, $onlineipmatches );
	$onlineip = $onlineipmatches [0] ? $onlineipmatches [0] : 'unknown';

	if ($format) {
		$ips = explode ( '.', $onlineip );
		for($i = 0; $i < 3; $i ++) {
			$ips [$i] = intval ( $ips [$i] );
		}
		return sprintf ( 'ddd', $ips [0], $ips [1], $ips [2] );
	} else {
		return $onlineip;
	}
}

/**
*用php的curl函数从网路上获取详细IP对应的地理未知
*/


function lazdf($ip){
	$url = "http://www.ip138.com/ips138.asp?ip=".$ip;
	$ipdz = http_request($url);
	preg_match("/<ul class=\"ul1\"><li>(.*?)<\/li>/i",$ipdz['body'],$jgarray);
	preg_match('/本站主数据：(.*)/', $jgarray[1], $place);
	echo   "欢迎来自".$place[1]."的朋友";

}

/**
* CURL封装
*/
function http_request($url,$post_data = array(),$header = array()) {
    $post_data = http_build_query($post_data);
    $header = $header ? $header : array ("Content-type: application/x-www-form-urlencoded; charset=gb2312");
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
    curl_setopt($ch, CURLOPT_HTTPHEADER,$header);
    $response = curl_exec($ch);
   
    if(curl_errno($ch))
    {
        $response = "ERROR:".curl_error($ch);
    }
    $status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);
    return array('body'=>$response,'status'=>$status) ;
} 


lazdf(get_online_ip());

注意：ip138的页面格式是gb2312的，所以这里我们用的字符编码也是gb2312的，将php文件也保存成gb2312格式，浏览器的编码也要选择gb2312，否则可能会出现乱码哦！