php通過ip地址獲取城市信息

下載qqwry.da

$ip = '1.202.241.99';
        $ip1num = 0;
        $ip2num = 0;
        $ipAddr1 = "";
        $ipAddr2 = "";
        $dat_path = storage_path().'\qqwry.dat';   //文件路徑
        if (!preg_match("/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/", $ip)) {
            return 'IP Address Error';
        }
        if (!$fd = @fopen($dat_path, 'rb')) {
            return 'IP date file not exists or access denied';
        }
        $ip = explode('.', $ip);
        $ipNum = $ip[0] * 16777216 + $ip[1] * 65536 + $ip[2] * 256 + $ip[3];
        //獲取IP數據索引開始和結束位置 ↓
        $DataBegin = fread($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 = $ipAllNum;
        //使用二分查找法從索引記錄中搜索匹配的IP記錄
        while ($ip1num > $ipNum || $ip2num < $ipNum) {
            $Middle = intval(($EndNum + $BeginNum) / 2);
            //偏移指針到索引位置讀取4個字節
            fseek($fd, $ipbegin + 7 * $Middle);
            $ipData1 = fread($fd, 4);
            if (strlen($ipData1) < 4) {
                fclose($fd);
                return 'System Error';
            }
            //提取出來的數據轉換成長整形，如果數據是負數則加上2的32次冪
            $ip1num = implode('', unpack('L', $ipData1));
            if ($ip1num < 0) $ip1num += pow(2, 32);
            //提取的長整型數大於我們IP地址則修改結束位置進行下一次循環
            if ($ip1num > $ipNum) {
                $EndNum = $Middle;
                continue;
            }
            //取完上一個索引後取下一個索引
            $DataSeek = fread($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) $ip2num += pow(2, 32);
            if ($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);
        if (preg_match('/http/i', $ipAddr2)) {
            $ipAddr2 = '';
        }
        $ipaddr = "$ipAddr1";
        $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';
        }
        $str = iconv("gb2312", "utf-8//IGNORE", $ipaddr); //這邊純真IP數據庫獲取到的gb2312格式的文字,要先轉成UTF8
        return $str;

t文件。