go语言生成任意长度的字符串

//生成随机字符串
func GetRandomString(l int) string {   
   str := "0123456789abcdefghijklmnopqrstuvwxyz"
   bytes := []byte(str)
   result := []byte{}
   r := rand.New(rand.NewSource(time.Now().UnixNano()))
   for i := 0; i < l; i++ {
      result = append(result, bytes[r.Intn(len(bytes))])
   }
   return string(result)
}