在Go中生成一个随机的，固定长度的字节数组

Question

I have a byte array, with a fixed length of 4.

token := make([]byte, 4)

I need to set each byte to a random byte. How can I do so, in the most efficient matter? The math/rand methods do not provide a Random Byte function, as far as I am concerned.

Perhaps there is a built-in way, or should I go with generating a random string and converting it to a byte array?

Answer 1

Package rand

import "math/rand" 

func Read

func Read(p []byte) (n int, err error)

Read generates len(p) random bytes from the default Source and writes them into p. It always returns len(p) and a nil error.

func (*Rand) Read

func (r *Rand) Read(p []byte) (n int, err error)

Read generates len(p) random bytes and writes them into p. It always returns len(p) and a nil error.

For example,

package main

import (
    "math/rand"
    "fmt"
)

func main() {
    token := make([]byte, 4)
    rand.Read(token)
    fmt.Println(token)
}

Output:

[187 163 35 30]