Go conversion between struct and byte array

Question

I am writing a client - server application in Go. I want to perform C-like type casting in Go.

E.g. in Go

type packet struct {
    opcode uint16
             


        

Answer 1

Thank you for answers and I am sure they work perfectly. But in my case I was more interested in parsing the []byte buffer received as network packet. I used following method to parse the buffer.

var data []byte // holds the network packet received
opcode := binary.BigEndian.Uint16(data) // this will get first 2 bytes to be interpreted as uint16 number
raw_data := data[2:len(data)] // this will copy rest of the raw data in to raw_data byte stream

While constructing a []byte stream from a struct, you can use following method

type packet struct {
    opcode uint16
    blk_no uint16
    data   string
}
pkt := packet{opcode: 2, blk_no: 1, data: "testing"}
var buf []byte = make([]byte, 50) // make sure the data string is less than 46 bytes
offset := 0
binary.BigEndian.PutUint16(buf[offset:], pkt.opcode)
offset = offset + 2
binary.BigEndian.PutUint16(buf[offset:], pkt.blk_no)
offset = offset + 2
bytes_copied := copy(buf[offset:], pkt.data)

I hope this gives general idea about how to convert []byte stream to struct and struct back to []byte stream.