golang byte 操作
// int to 4 bytes
func intTo4Bytes(i int) []byte {
buf := bytes.NewBuffer([]byte{})
tmp := uint32(i)
binary.Write(buf, binary.BigEndian, tmp)
return buf.Bytes()
}
// int to 2 bytes
func intTo2Bytes(i int) []byte {
buf := bytes.NewBuffer([]byte{})
tmp := uint16(i)
binary.Write(buf, binary.BigEndian, tmp)
return buf.Bytes()
}