PHP：根据IP地址获取所在城市

文件目录：

ipLocation
-----qqwry
----------QQWry.Dat
-----ipCity.class.php

ipCity.class.php文件代码：

 $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 == '' ) {
            $useripaddr = 'No Data';
        } elseif ( !$this->is_utf8( $useripaddr ) ) {
            $useripaddr = iconv( 'GBK', 'UTF-8', $useripaddr );
        }
        return $useripaddr;
    }

    /**
     * 判断是否我utf-8编码的字符串
     * @param type $string
     * @return boolean
     */
    private function is_utf8( $string ) {
        if ( preg_match( "/^([" . chr( 228 ) . "-" . chr( 233 ) . "]{1}[" . chr( 128 ) . "-" . chr( 191 ) . "]{1}[" . chr( 128 ) . "-" . chr( 191 ) . "]{1}){1}/", $string ) == true || preg_match( "/([" . chr( 228 ) . "-" . chr( 233 ) . "]{1}[" . chr( 128 ) . "-" . chr( 191 ) . "]{1}[" . chr( 128 ) . "-" . chr( 191 ) . "]{1}){1}$/", $string ) == true || preg_match( "/([" . chr( 228 ) . "-" . chr( 233 ) . "]{1}[" . chr( 128 ) . "-" . chr( 191 ) . "]{1}[" . chr( 128 ) . "-" . chr( 191 ) . "]{1}){2,}/", $string ) == true ) {
            return true;
        } else {
            return false;
        }
    }

}

QQWry.Dat文件可以在百度上搜索或者需要的发你邮箱来，我通过邮箱发给你。

使用演示：

include FCPATH . 'plugin/ipLocation/ipCity.class.php';
$city = new ipCity();
$addr = $city->getCity( '172.0.0.1' );
echo $addr; // echo 本地地址