golang仿AS3写的ByteArray

rockyf · · 4931 次点击 · · 开始浏览

这是一个创建于的文章，其中的信息可能已经有所发展或是发生改变。

用golang写了个仿AS3写的ByteArray，稍微有点差别，demo能成功运行，还未进行其他测试

主要参考的是golang自带库里的Buffer，结合了binary

来看看demo：

 1 package main
 2 
 3 import (
 4     "tbs"
 5     "fmt"
 6 )
 7 
 8 func main() {
 9     var ba *tbs.ByteArray = tbs.CreateByteArray([]byte{})
10 
11     ba.WriteBytes([]byte("abc"))
12     ba.WriteByte('A')
13     ba.WriteBool(true)
14     ba.WriteBool(false)
15     ba.WriteInt8(11)
16     ba.WriteInt16(123)
17     ba.WriteInt32(123)
18     ba.WriteInt64(513)
19     ba.WriteFloat32(123.456)
20     ba.WriteFloat64(456.789)
21     ba.WriteString("hello ")
22     ba.WriteUTF("world!")
23 
24     bytes := make([]byte, 3)
25     fmt.Println(ba.ReadBytes(bytes, 3, 0))
26     fmt.Println(ba.ReadByte())
27     fmt.Println(ba.ReadBool())
28     fmt.Println(ba.ReadBool())
29     fmt.Println(ba.ReadInt8())
30     fmt.Println(ba.ReadInt16())
31     fmt.Println(ba.ReadInt32())
32     fmt.Println(ba.ReadInt64())
33     fmt.Println(ba.ReadFloat32())
34     fmt.Println(ba.ReadFloat64())
35     fmt.Println(ba.ReadString(6))
36     fmt.Println(ba.ReadUTF())
37 
38     byte,err := ba.ReadByte()
39     if err == nil{
40         fmt.Println(byte)
41     }else{
42         fmt.Println("end of file")
43     }
44 
45     ba.Seek(3)    //back to 3
46     fmt.Println(ba.ReadByte())
47     ba.Seek(39)    //back to 39
48     fmt.Printf("ba has %d bytes available!\n", ba.Available())
49     fmt.Println(ba.ReadUTF())
50 }

demo中测试所有的方法

付上代码:

  1 package tbs
  2 
  3 import (
  4     "encoding/binary"
  5     "io"
  6 )
  7 
  8 type ByteArray struct {
  9     buf      []byte
 10     posWrite int
 11     posRead  int
 12     endian   binary.ByteOrder
 13 }
 14 
 15 var ByteArrayEndian binary.ByteOrder = binary.BigEndian
 16 
 17 func CreateByteArray(bytes []byte) *ByteArray {
 18     var ba *ByteArray
 19     if len(bytes) > 0 {
 20         ba = &ByteArray{buf: bytes}
 21     } else {
 22         ba = &ByteArray{}
 23     }
 24 
 25     ba.endian = binary.BigEndian
 26 
 27     return ba
 28 }
 29 
 30 func (this *ByteArray) Length() int {
 31     return len(this.buf)
 32 }
 33 
 34 func (this *ByteArray) Available() int {
 35     return this.Length() - this.posRead
 36 }
 37 
 38 func (this *ByteArray) SetEndian(endian binary.ByteOrder) {
 39     this.endian = endian
 40 }
 41 
 42 func (this *ByteArray) GetEndian() binary.ByteOrder {
 43     if this.endian == nil {
 44         return ByteArrayEndian
 45     }
 46     return this.endian
 47 }
 48 
 49 func (this *ByteArray) grow(l int) {
 50     if l == 0 {
 51         return
 52     }
 53     space := len(this.buf) - this.posWrite
 54     if space >= l {
 55         return
 56     }
 57 
 58     needGrow := l - space
 59     bufGrow := make([]byte, needGrow)
 60 
 61     this.buf = Merge(this.buf, bufGrow)
 62 }
 63 
 64 func (this *ByteArray) SetWritePos(pos int) error{
 65     if pos > this.Length(){
 66         this.posWrite = this.Length()
 67         return io.EOF
 68     }else{
 69         this.posWrite = pos
 70     }
 71     return nil
 72 }
 73 
 74 func (this *ByteArray) SetWriteEnd(){
 75     this.SetWritePos(this.Length())
 76 }
 77 
 78 func (this *ByteArray) GetWritePos() int{
 79     return this.posWrite
 80 }
 81 
 82 func (this *ByteArray) SetReadPos(pos int) error{
 83     if pos > this.Length(){
 84         this.posRead = this.Length()
 85         return io.EOF
 86     }else{
 87         this.posRead = pos
 88     }
 89     return nil
 90 }
 91 
 92 func (this *ByteArray) SetReadEnd(){
 93     this.SetReadPos(this.Length())
 94 }
 95 
 96 func (this *ByteArray) GetReadPos() int{
 97     return this.posRead
 98 }
 99 
100 func (this *ByteArray) Seek(pos int) error{
101     err := this.SetWritePos(pos)
102     this.SetReadPos(pos)
103 
104     return err
105 }
106 
107 func (this *ByteArray) Reset() {
108     this.buf = []byte{}
109     this.Seek(0)
110 }
111 
112 func (this *ByteArray) Bytes() []byte {
113     return this.buf
114 }
115 
116 func (this *ByteArray) BytesAvailable() []byte {
117     return this.buf[this.posRead:]
118 }
119 //==========write
120 func (this *ByteArray) Write(bytes []byte) (l int, err error) {
121     this.grow(len(bytes))
122 
123     l = copy(this.buf[this.posWrite:], bytes)
124     this.posWrite += l
125 
126     return l, nil
127 }
128 
129 func (this *ByteArray) WriteBytes(bytes []byte) (l int, err error) {
130     return this.Write(bytes)
131 }
132 
133 func (this *ByteArray) WriteByte(b byte) {
134     bytes := make([]byte, 1)
135     bytes[0] = b
136     this.WriteBytes(bytes)
137 }
138 
139 func (this *ByteArray) WriteInt8(value int8) {
140     binary.Write(this, this.endian, &value)
141 }
142 
143 func (this *ByteArray) WriteInt16(value int16){
144     binary.Write(this, this.endian, &value)
145 }
146 
147 func (this *ByteArray) WriteInt32(value int32){
148     binary.Write(this, this.endian, &value)
149 }
150 
151 func (this *ByteArray) WriteInt64(value int64){
152     binary.Write(this, this.endian, &value)
153 }
154 
155 func (this *ByteArray) WriteFloat32(value float32){
156     binary.Write(this, this.endian, &value)
157 }
158 
159 func (this *ByteArray) WriteFloat64(value float64){
160     binary.Write(this, this.endian, &value)
161 }
162 
163 func (this *ByteArray) WriteBool(value bool){
164     var bb byte
165     if value {
166         bb = 1
167     } else {
168         bb = 0
169     }
170 
171     this.WriteByte(bb)
172 }
173 
174 func (this *ByteArray) WriteString(value string){
175     this.WriteBytes([]byte(value))
176 }
177 
178 func (this *ByteArray) WriteUTF(value string){
179     this.WriteInt16(int16(len(value)))
180     this.WriteBytes([]byte(value))
181 }
182 //==========read
183 
184 func (this *ByteArray) Read(bytes []byte) (l int, err error){
185     if len(bytes) == 0 {
186         return
187     }
188     if len(bytes) > this.Length() - this.posRead{
189         return 0, io.EOF
190     }
191     l = copy(bytes, this.buf[this.posRead:])
192     this.posRead += l
193 
194     return l, nil
195 }
196 
197 func (this *ByteArray) ReadBytes(bytes []byte, length int, offset int) (l int, err error){
198     return this.Read(bytes[offset:offset + length])
199 }
200 
201 func (this *ByteArray) ReadByte() (b byte, err error){
202     bytes := make([]byte, 1)
203     _, err = this.ReadBytes(bytes, 1, 0)
204 
205     if err == nil{
206         b = bytes[0]
207     }
208 
209     return
210 }
211 
212 func (this *ByteArray) ReadInt8() (ret int8, err error){
213     err = binary.Read(this, this.endian, &ret)
214     return
215 }
216 
217 func (this *ByteArray) ReadInt16() (ret int16, err error){
218     err = binary.Read(this, this.endian, &ret)
219     return
220 }
221 
222 func (this *ByteArray) ReadInt32() (ret int32, err error){
223     err = binary.Read(this, this.endian, &ret)
224     return
225 }
226 
227 func (this *ByteArray) ReadInt64() (ret int64, err error){
228     err = binary.Read(this, this.endian, &ret)
229     return
230 }
231 
232 func (this *ByteArray) ReadFloat32() (ret float32, err error){
233     err = binary.Read(this, this.endian, &ret)
234     return
235 }
236 
237 func (this *ByteArray) ReadFloat64() (ret float64, err error){
238     err = binary.Read(this, this.endian, &ret)
239     return
240 }
241 
242 func (this *ByteArray) ReadBool() (ret bool, err error){
243     var bb byte
244     bb, err = this.ReadByte()
245     if err == nil{
246         if bb == 1 {
247             ret = true
248         } else {
249             ret = false
250         }
251     }else{
252         ret = false
253     }
254     return
255 }
256 
257 func (this *ByteArray) ReadString(length int) (ret string, err error){
258     bytes := make([]byte, length)
259     _, err = this.ReadBytes(bytes, length, 0)
260     if err == nil{
261         ret = string(bytes)
262     }else{
263         ret = "";
264     }
265     return
266 }
267 
268 func (this *ByteArray) ReadUTF() (ret string, err error){
269     var l int16
270     l, err = this.ReadInt16()
271 
272     if err != nil{
273         return "", err
274     }
275 
276     return this.ReadString(int(l))
277 }