在Go中解析字符串中的多个整数？

Question

sorry for the title , i don't know how to say that

i have a questions about this code

func ip2long(ip string) (ret int64) {
  p:= strings.Split(ip, ".")
  n, _:= strconv.Atoi(p[0])
  ret += int64(n)*16777216 
  n, _= strconv.Atoi(p[1])
  ret += int64(n)*65536 
  n, _= strconv.Atoi(p[2])
  ret += int64(n)*256
  n, _= strconv.Atoi(p[3])
  ret += int64(n)

  return 
}

I want to convert an ip address to integer number

you see I have wrote such ugly code

first retrive number from strconv.Atoi then convert it to int64

How to simplify this ?

Answer 1

If you want to parse multiple integers from a string, try the Sscanf function, like this:

func main() {
    var ip [4] uint32
    addr := "192.168.0.1"
    _, err := fmt.Sscanf(addr, "%d.%d.%d.%d", &ip[0], &ip[1], &ip[2], &ip[3])
    if err != nil {
        fmt.Println(err)
        return
    }
    fmt.Println(ip)
    fmt.Println(ip[0]<<24 + ip[1]<<16 + ip[2]<<8 + ip[3])
}