Go语言中你所不知道的位操作用法

package main

import (
 "fmt"
)

type users struct {
 name string
 flag uint8
 vip bool
 svip bool
 blue bool
 red bool
 yellow bool
}

func setVip(user users) users {
 user.vip = true
 return user
}

func isVip(user users) {
 if user.vip {
  fmt.Println("user is vip")
 } else {
  fmt.Println("user is not vip")
 }
}

func binaryTest() {
 var user users
 user.name = "test01"
 user.vip = true
 isVip(user)
 user.vip = false
 isVip(user)
}

func main() {
 binaryTest()

}

package main

import (
  "fmt"
)

type users struct {
  name string
  flag uint8
}

// 这里通过位移的方式默认00000 从左边一次为vip,svip,blue,red,yellow
const (
  vip  = 1
  svip = (1 << 1)
  blue = (1 << 2)
  red  = (1 << 3)
  yello = (1 << 4)
)

// setFlag 用于设置用户开通了哪些特权
func setFlag(user users, isSet bool, typeFlag uint8) users {
  if isSet == true {
    user.flag = user.flag | typeFlag
  } else {
    user.flag = user.flag ^ typeFlag
  }
  return user
}

//isFlag 用于判断用户是否开通某项特权
func isFlag(user users, typeFlag uint8) bool {
  result := user.flag & typeFlag
  return result == typeFlag
}

func binaryTest() {
  var user users
  user.name = "coder"
  user.flag = 0

  //判断用户是否是vip
  result := isFlag(user, vip)
  fmt.Printf("user is Vip:%t\n", result)

  //给用户开通vip,并看用户是否开通vip
  user = setFlag(user, true, vip)
  result = isFlag(user, vip)
  fmt.Printf("user is Vip:%t\n", result)

  //取消用户的vip，并查看用户是否还是vip
  user = setFlag(user, false, vip)
  result = isFlag(user, vip)
  fmt.Printf("user is Vip:%t\n", result)
}

func main() {
  binaryTest()
}

package main

import "fmt"

func main() {
  x := 2
  y := 4
  fmt.Println(x<<1)
  fmt.Println(y1)
}output:4 2