Go语言 序列化反序列化二进制包

包的定义格式是长度，校验码和json内容

package mainimport ("bytes""encoding/binary""encoding/json""fmt""hash/crc32""io""net""os")type Register struct {ACTION int32SID    int32}type Packet struct {length uint32crc32  uint32info   string}func (p Packet) Encode() []byte {buf2 := new(bytes.Buffer)var length int = len([]byte(p.info))err := binary.Write(buf2, binary.LittleEndian, (int32)(length))checkError(err)err = binary.Write(buf2, binary.LittleEndian, []byte(p.info))checkError(err)buf := new(bytes.Buffer)p.length = uint32(buf2.Len() + 8)err = binary.Write(buf, binary.LittleEndian, p.length)checkError(err)p.crc32 = crc32.ChecksumIEEE(buf2.Bytes())err = binary.Write(buf, binary.LittleEndian, p.crc32)checkError(err)err = binary.Write(buf, binary.LittleEndian, buf2.Bytes())checkError(err)return buf.Bytes()}func (p *Packet) Decode(buff []byte) {buf := bytes.NewBuffer(buff)err := binary.Read(buf, binary.LittleEndian, &(p.length))checkError(err)fmt.Println(p.length)err = binary.Read(buf, binary.LittleEndian, &(p.crc32))checkError(err)buf2 := bytes.NewBuffer(buff[8:])crc := crc32.ChecksumIEEE(buf2.Bytes())if crc != p.crc32 {fmt.Errorf(" crc not check")}p.info = (string)(buf2.Bytes())fmt.Printf("%s", p.info)}func main() {m := Register{20004, 6}b, err := json.Marshal(m)checkError(err)var packet Packetpacket.info = string(b)buf := packet.Encode()fmt.Println(len(buf))var msg Packetmsg.Decode(buf)os.Exit(0)}func checkError(err error) {if err != nil {fmt.Fprintf(os.Stderr, "Fatal error: %s", err.Error())os.Exit(1)}}