diff --git a/binding/golang/ip2region/ip2Region.go b/binding/golang/ip2region/ip2Region.go
index adaf382..f348243 100644
--- a/binding/golang/ip2region/ip2Region.go
+++ b/binding/golang/ip2region/ip2Region.go
@@ -1,11 +1,13 @@
 package ip2region
 
 import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"net"
 	"os"
 	"strings"
-	"strconv"
-	"io/ioutil"
-	"errors"
 )
 
 const (
@@ -13,19 +15,14 @@ const (
 	TOTAL_HEADER_LENGTH = 8192
 )
 
-var err error
-var ipInfo IpInfo
-
 type Ip2Region struct {
 	// db file handler
 	dbFileHandler *os.File
 
-
 	//header block info
-
-	headerSip     []int64
-	headerPtr     []int64
-	headerLen     int64
+	headerSip []int64
+	headerPtr []int64
+	headerLen int64
 
 	// super block index info
 	firstIndexPtr int64
@@ -34,9 +31,8 @@ type Ip2Region struct {
 
 	// for memory mode only
 	// the original db binary string
-
-	dbBinStr      []byte
-	dbFile        string
+	dbBinStr []byte
+	dbFile   string
 }
 
 type IpInfo struct {
@@ -48,40 +44,36 @@ type IpInfo struct {
 	ISP      string
 }
 
-func (ip IpInfo)String() string {
-	return strconv.FormatInt(ip.CityId, 10) + "|" + ip.Country + "|" + ip.Region + "|" + ip.Province + "|" + ip.City + "|" + ip.ISP
+func (ip IpInfo) String() string {
+	return fmt.Sprintf("%d|%s|%s|%s|%s|%s", ip.CityId, ip.Country, ip.Region, ip.Province, ip.City, ip.ISP)
 }
 
 func getIpInfo(cityId int64, line []byte) IpInfo {
-
 	lineSlice := strings.Split(string(line), "|")
-	ipInfo := IpInfo{}
 	length := len(lineSlice)
-	ipInfo.CityId = cityId
 	if length < 5 {
-		for i := 0; i <= 5 - length; i++ {
+		for i := 0; i <= 5-length; i++ {
 			lineSlice = append(lineSlice, "")
 		}
 	}
-
-	ipInfo.Country = lineSlice[0]
-	ipInfo.Region = lineSlice[1]
-	ipInfo.Province = lineSlice[2]
-	ipInfo.City = lineSlice[3]
-	ipInfo.ISP = lineSlice[4]
-	return ipInfo
+	return IpInfo{
+		CityId:   cityId,
+		Country:  lineSlice[0],
+		Region:   lineSlice[1],
+		Province: lineSlice[2],
+		City:     lineSlice[3],
+		ISP:      lineSlice[4],
+	}
 }
 
 func New(path string) (*Ip2Region, error) {
-
 	file, err := os.Open(path)
 	if err != nil {
 		return nil, err
 	}
-
 	return &Ip2Region{
-		dbFile:path,
-		dbFileHandler:file,
+		dbFile:        path,
+		dbFileHandler: file,
 	}, nil
 }
 
@@ -91,56 +83,50 @@ func (this *Ip2Region) Close() {
 
 func (this *Ip2Region) MemorySearch(ipStr string) (ipInfo IpInfo, err error) {
 	ipInfo = IpInfo{}
-
 	if this.totalBlocks == 0 {
 		this.dbBinStr, err = ioutil.ReadFile(this.dbFile)
-
 		if err != nil {
-
 			return ipInfo, err
 		}
-
 		this.firstIndexPtr = getLong(this.dbBinStr, 0)
 		this.lastIndexPtr = getLong(this.dbBinStr, 4)
-		this.totalBlocks = (this.lastIndexPtr - this.firstIndexPtr) / INDEX_BLOCK_LENGTH + 1
+		this.totalBlocks = (this.lastIndexPtr-this.firstIndexPtr)/INDEX_BLOCK_LENGTH + 1
 	}
-
 	ip, err := ip2long(ipStr)
 	if err != nil {
 		return ipInfo, err
 	}
-
-	h := this.totalBlocks
-	var dataPtr, l int64;
-	for (l <= h) {
-
+	var (
+		h          = this.totalBlocks
+		dataPtr, l int64
+	)
+	for l <= h {
 		m := (l + h) >> 1
-		p := this.firstIndexPtr + m * INDEX_BLOCK_LENGTH
+		p := this.firstIndexPtr + m*INDEX_BLOCK_LENGTH
 		sip := getLong(this.dbBinStr, p)
 		if ip < sip {
 			h = m - 1
 		} else {
-			eip := getLong(this.dbBinStr, p + 4)
+			eip := getLong(this.dbBinStr, p+4)
 			if ip > eip {
 				l = m + 1
 			} else {
-				dataPtr = getLong(this.dbBinStr, p + 8)
-				break;
+				dataPtr = getLong(this.dbBinStr, p+8)
+				break
 			}
 		}
 	}
 	if dataPtr == 0 {
 		return ipInfo, errors.New("not found")
 	}
-
-	dataLen := ((dataPtr >> 24) & 0xFF)
-	dataPtr = (dataPtr & 0x00FFFFFF);
-	ipInfo = getIpInfo(getLong(this.dbBinStr, dataPtr), this.dbBinStr[(dataPtr) + 4:dataPtr + dataLen])
+	dataLen := (dataPtr >> 24) & 0xFF
+	dataPtr = dataPtr & 0x00FFFFFF
+	ipInfo = getIpInfo(getLong(this.dbBinStr, dataPtr), this.dbBinStr[(dataPtr)+4:dataPtr+dataLen])
 	return ipInfo, nil
 
 }
 
-func (this *Ip2Region)BinarySearch(ipStr string) (ipInfo IpInfo, err error) {
+func (this *Ip2Region) BinarySearch(ipStr string) (ipInfo IpInfo, err error) {
 	ipInfo = IpInfo{}
 	if this.totalBlocks == 0 {
 		this.dbFileHandler.Seek(0, 0)
@@ -148,34 +134,27 @@ func (this *Ip2Region)BinarySearch(ipStr string) (ipInfo IpInfo, err error) {
 		this.dbFileHandler.Read(superBlock)
 		this.firstIndexPtr = getLong(superBlock, 0)
 		this.lastIndexPtr = getLong(superBlock, 4)
-		this.totalBlocks = (this.lastIndexPtr - this.firstIndexPtr) / INDEX_BLOCK_LENGTH + 1
+		this.totalBlocks = (this.lastIndexPtr-this.firstIndexPtr)/INDEX_BLOCK_LENGTH + 1
 	}
-
-	var l, dataPtr, p int64
-
-	h := this.totalBlocks
-
+	var (
+		h             = this.totalBlocks
+		l, dataPtr, p int64
+	)
 	ip, err := ip2long(ipStr)
-
 	if err != nil {
 		return
 	}
-
-	for (l <= h) {
+	for l <= h {
 		m := (l + h) >> 1
-
 		p = m * INDEX_BLOCK_LENGTH
-
-		_, err = this.dbFileHandler.Seek(this.firstIndexPtr + p, 0)
+		_, err = this.dbFileHandler.Seek(this.firstIndexPtr+p, 0)
 		if err != nil {
 			return
 		}
-
 		buffer := make([]byte, INDEX_BLOCK_LENGTH)
 		_, err = this.dbFileHandler.Read(buffer)
-
 		if err != nil {
-
+			return
 		}
 		sip := getLong(buffer, 0)
 		if ip < sip {
@@ -186,129 +165,119 @@ func (this *Ip2Region)BinarySearch(ipStr string) (ipInfo IpInfo, err error) {
 				l = m + 1
 			} else {
 				dataPtr = getLong(buffer, 8)
-				break;
+				break
 			}
 		}
-
 	}
-
 	if dataPtr == 0 {
-		err = errors.New("not found")
-		return
+		return ipInfo, errors.New("not found")
 	}
-
-	dataLen := ((dataPtr >> 24) & 0xFF)
-	dataPtr = (dataPtr & 0x00FFFFFF);
-
+	dataLen := (dataPtr >> 24) & 0xFF
+	dataPtr = dataPtr & 0x00FFFFFF
 	this.dbFileHandler.Seek(dataPtr, 0)
 	data := make([]byte, dataLen)
 	this.dbFileHandler.Read(data)
 	ipInfo = getIpInfo(getLong(data, 0), data[4:dataLen])
-	err = nil
 	return
 }
 
 func (this *Ip2Region) BtreeSearch(ipStr string) (ipInfo IpInfo, err error) {
-	ipInfo = IpInfo{}
 	ip, err := ip2long(ipStr)
-
+	if err != nil {
+		return
+	}
+	ipInfo = IpInfo{}
 	if this.headerLen == 0 {
 		this.dbFileHandler.Seek(8, 0)
-
 		buffer := make([]byte, TOTAL_HEADER_LENGTH)
 		this.dbFileHandler.Read(buffer)
-		var idx int64;
+		var idx int64
 		for i := 0; i < TOTAL_HEADER_LENGTH; i += 8 {
 			startIp := getLong(buffer, int64(i))
-			dataPar := getLong(buffer, int64(i + 4))
+			dataPar := getLong(buffer, int64(i+4))
 			if dataPar == 0 {
 				break
 			}
-
 			this.headerSip = append(this.headerSip, startIp)
 			this.headerPtr = append(this.headerPtr, dataPar)
-			idx ++;
+			idx++
 		}
-
 		this.headerLen = idx
 	}
 
-	var l, sptr, eptr int64
-	h := this.headerLen
-
+	var (
+		l, sptr, eptr int64
+		h             = this.headerLen
+	)
 	for l <= h {
-		m := int64(l + h) >> 1
+		m := (l + h) >> 1
 		if m < this.headerLen {
 			if ip == this.headerSip[m] {
 				if m > 0 {
-					sptr = this.headerPtr[m - 1]
+					sptr = this.headerPtr[m-1]
 					eptr = this.headerPtr[m]
 				} else {
 					sptr = this.headerPtr[m]
-					eptr = this.headerPtr[m + 1]
+					eptr = this.headerPtr[m+1]
 				}
 				break
 			}
 			if ip < this.headerSip[m] {
 				if m == 0 {
 					sptr = this.headerPtr[m]
-					eptr = this.headerPtr[m + 1]
+					eptr = this.headerPtr[m+1]
 					break
-				} else if ip > this.headerSip[m - 1] {
-					sptr = this.headerPtr[m - 1]
+				} else if ip > this.headerSip[m-1] {
+					sptr = this.headerPtr[m-1]
 					eptr = this.headerPtr[m]
 					break
 				}
 				h = m - 1
 			} else {
-				if m == this.headerLen - 1 {
-					sptr = this.headerPtr[m - 1]
+				if m == this.headerLen-1 {
+					sptr = this.headerPtr[m-1]
 					eptr = this.headerPtr[m]
 					break
-				} else if ip <= this.headerSip[m + 1] {
-					sptr = this.headerPtr[m ]
-					eptr = this.headerPtr[m + 1]
+				} else if ip <= this.headerSip[m+1] {
+					sptr = this.headerPtr[m]
+					eptr = this.headerPtr[m+1]
 					break
 				}
 				l = m + 1
 			}
 		}
-
 	}
 
 	if sptr == 0 {
-		err = errors.New("not found")
-		return
+		return ipInfo, errors.New("not found")
 	}
 
 	blockLen := eptr - sptr
 	this.dbFileHandler.Seek(sptr, 0)
-	index := make([]byte, blockLen + INDEX_BLOCK_LENGTH)
+	index := make([]byte, blockLen+INDEX_BLOCK_LENGTH)
 	this.dbFileHandler.Read(index)
 	var dataptr int64
 	h = blockLen / INDEX_BLOCK_LENGTH
 	l = 0
 
 	for l <= h {
-		m := int64(l + h) >> 1
+		m := (l + h) >> 1
 		p := m * INDEX_BLOCK_LENGTH
 		sip := getLong(index, p)
 		if ip < sip {
-			h = m - 1;
+			h = m - 1
 		} else {
-			eip := getLong(index, p + 4)
+			eip := getLong(index, p+4)
 			if ip > eip {
 				l = m + 1
 			} else {
-				dataptr = getLong(index, p + 8)
+				dataptr = getLong(index, p+8)
 				break
 			}
 		}
 	}
-
 	if dataptr == 0 {
-		err = errors.New("not found")
-		return
+		return ipInfo, errors.New("not found")
 	}
 
 	dataLen := (dataptr >> 24) & 0xFF
@@ -322,28 +291,13 @@ func (this *Ip2Region) BtreeSearch(ipStr string) (ipInfo IpInfo, err error) {
 }
 
 func getLong(b []byte, offset int64) int64 {
-
-	val := (int64(b[offset ]) |
-		int64(b[offset + 1]) << 8 |
-		int64(b[offset + 2]) << 16 |
-		int64(b[offset + 3]) << 24)
-
-	return val
-
+	return int64(b[offset]) | int64(b[offset+1])<<8 | int64(b[offset+2])<<16 | int64(b[offset+3])<<24
 }
 
-func ip2long(IpStr string) (int64, error) {
-	bits := strings.Split(IpStr, ".")
-	if len(bits) != 4 {
+func ip2long(ipStr string) (int64, error) {
+	ipv4 := net.ParseIP(ipStr)
+	if ipv4 == nil {
 		return 0, errors.New("ip format error")
 	}
-
-	var sum int64
-	for i, n := range bits {
-		bit, _ := strconv.ParseInt(n, 10, 64)
-		sum += bit << uint(24 - 8 * i)
-	}
-
-	return sum, nil
+	return int64(binary.BigEndian.Uint32(ipv4[12:])), nil
 }
-
diff --git a/binding/golang/ip2region/ip2Region_test.go b/binding/golang/ip2region/ip2Region_test.go
index 5fb717c..e7c9e74 100644
--- a/binding/golang/ip2region/ip2Region_test.go
+++ b/binding/golang/ip2region/ip2Region_test.go
@@ -5,7 +5,7 @@ import (
 )
 
 func BenchmarkBtreeSearch(B *testing.B) {
-	region, err := New("../../data/ip2region.db ")
+	region, err := New("../../../data/ip2region.db")
 	if err != nil {
 		B.Error(err)
 	}
@@ -16,7 +16,7 @@ func BenchmarkBtreeSearch(B *testing.B) {
 }
 
 func BenchmarkMemorySearch(B *testing.B) {
-	region, err := New("../../data/ip2region.db ")
+	region, err := New("../../../data/ip2region.db")
 	if err != nil {
 		B.Error(err)
 	}
@@ -27,7 +27,7 @@ func BenchmarkMemorySearch(B *testing.B) {
 }
 
 func BenchmarkBinarySearch(B *testing.B) {
-	region, err := New("../../data/ip2region.db ")
+	region, err := New("../../../data/ip2region.db")
 	if err != nil {
 		B.Error(err)
 	}