阅读目录
一、Time
二、常用时间总结
三、定时器
一、Time
//时间类型
func testTime(){
now := time.Now()
fmt.Println(now)
fmt.Printf("%d-%02d-%02d %02d:%02d:%02d\n", now.Year(), now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())
}
//时间戳
func testTimestamp(){
now := time.Now()
timestamp1 := now.Unix() //时间戳
timestamp2 := now.UnixNano() //纳秒时间戳
fmt.Printf("current timestamp1:%v\n", timestamp1)
fmt.Printf("current timestamp2:%v\n", timestamp2)
}
//时间转换
func testTimeTransform(){
timestamp := time.Now().Unix() //时间戳
//时间戳转时间类型
unix := time.Unix(timestamp, 0)
fmt.Printf("%d-%02d-%02d %02d:%02d:%02d\n", unix.Year(), unix.Month(), unix.Day(), unix.Hour(), unix.Minute(), unix.Second())
}
//时间操作
func testTimeOperate(){
//add
now := time.Now()
newTime := now.Add(time.Hour)
fmt.Println(newTime)
//sub
newTimeDuration := newTime.Sub(now)
//返回一个时间区
fmt.Println(newTimeDuration)
}
//时间格式化
func testTimeFormatAndParse(){
now := time.Now()
// 24小时制
fmt.Println(now.Format("2006-01-02 15:04:05.000 Mon Jan"))
// 12小时制
fmt.Println(now.Format("2006-01-02 03:04:05.000 PM Mon Jan"))
fmt.Println(now.Format("2006/01/02 15:04"))
fmt.Println(now.Format("15:04 2006/01/02"))
fmt.Println(now.Format("2006/01/02"))
//默认UTC时间
//t, _ := time.Parse("2006-01-02 15:04:05", "2020-05-07 09:14:00")
t, _ := time.ParseInLocation("2006-01-02 15:04:05", "2020-05-07 10:30:52", time.Local)
fmt.Println(t)
fmt.Println(time.Now().Sub(t).Hours())
}
//时区
func testTimezone(){
now := time.Now()
fmt.Println(now)
// 加载时区
loc, err := time.LoadLocation("Asia/Shanghai")
if err != nil {
fmt.Println(err)
return
}
// 按照指定时区和指定格式解析字符串时间
timeObj, err := time.ParseInLocation("2006/01/02 15:04:05", "2020/05/07 10:31:20", loc)
if err != nil {
fmt.Println(err)
return
}
fmt.Println(timeObj)
fmt.Println(timeObj.Sub(now))
}
//对于 json,使用的是 time.RFC3339Nano 这种格式。通常程序中不使用这种格式。解决办法是定义自己的类型。
type oftenTime time.Time
func(o oftenTime) MarshalJSON() ([]byte, error) {
t := time.Time(o)
//判断类型
if y := t.Year(); y < 0 || y >= 10000 {
return nil, errors.New("Time.MarshalJSON: year outside of range [0,9999]")
}
//JSON,双引号不能少
return []byte(t.Format(`"2006-01-02 15:04:05"`)), nil
}
func testTimeJson(){
o := oftenTime(time.Now())
bytes, e := json.Marshal(o)
fmt.Println(string(bytes), e)
}
//获取当前时间整点的 Time 实例
func testRoundAndTruncate(){
fmt.Println(time.Now().Truncate(1 * time.Hour))
fmt.Println(time.Now().Round(1 * time.Hour))
t, _ := time.ParseInLocation("2006-01-02 15:04:05", "2020-05-08 10:30:52", time.Local)
// 整点(向下取整)
fmt.Println(t.Truncate(1 * time.Hour))
// 整点(最接近)
fmt.Println(t.Round(1 * time.Hour))
// 整分(向下取整)
fmt.Println(t.Truncate(1 * time.Minute))
// 整分(最接近)
fmt.Println(t.Round(1 * time.Minute))
t2, _ := time.ParseInLocation("2006-01-02 15:04:05", t.Format("2006-01-02 15:00:00"), time.Local)
fmt.Println(t2)
}
二、常用时间总结
//获取每月第一天
func GetFirstDateOfMonth(t time.Time) time.Time {
t = t.AddDate(0, 0, -t.Day() + 1)
return GetZeroTime(t)
}
func GetLastDateOfMonth(t time.Time) time.Time {
return GetFirstDateOfMonth(t).AddDate(0, 1, -1)
}
//获取某一天的0点时间
func GetZeroTime(t time.Time) time.Time {
return time.Date(t.Year(), t.Month(), t.Day(), 0, 0, 0, 0, t.Location())
}
//获取是周几
func GetWeekDay(t time.Time) int {
year, month, day := t.Year(), int(t.Month()), t.Day()
var weekday = [7]int{7, 1, 2, 3, 4, 5, 6}
var y, m , c int
if month >= 3 {
m = month
y = year % 100
c = year / 100
} else {
m = month + 12
y = (year - 1) % 100
c = (year - 1) / 100
}
week := y + (y / 4) + (c / 4) - 2*c + ((26 * (m + 1)) / 10) + day - 1
if week < 0 {
week = 7 - (-week)%7
} else {
week = week % 7
}
return weekday[week]
}
//获取本周周日的日期
func GetLastDateOfWeek(t time.Time, fmtStr string) (dayStr string) {
dayObj := GetZeroTime(t)
if t.Weekday() == time.Sunday{
dayStr = dayObj.Format(fmtStr)
}else{
dayStr = dayObj.AddDate(0, 0, 7-int(t.Weekday())).Format(fmtStr)
}
return
}
//获取本周周一的日期
func GetFirstDateOfWeek(t time.Time, fmtStr string) (dayStr string) {
dayObj := GetZeroTime(t)
if t.Weekday() == time.Monday {
//修改hour、min、sec = 0后格式化
dayStr = dayObj.Format(fmtStr)
}else{
offset := int(time.Monday - t.Weekday())
if offset > 0 {
offset = -6
}
dayStr = dayObj.AddDate(0, 0, offset).Format(fmtStr)
}
return
}
//获取上周周一日期
func GetLastWeekFirstDate(t time.Time, fmtStr string) (day string, err error) {
monday := GetFirstDateOfWeek(t, fmtStr)
dayObj, err := time.Parse(fmtStr, monday)
if err != nil{
return
}
day = dayObj.AddDate(0, 0, -7).Format(fmtStr)
return
}
//获取上周最后一天
func GetLastWeekLastDate(t time.Time, fmtStr string) (day string, err error) {
sunday := GetFirstDateOfWeek(t, fmtStr)
dayObj, err := time.Parse(fmtStr, sunday)
if err != nil{
return
}
day = dayObj.AddDate(0, 0, -1).Format(fmtStr)
return
}
三、定时器
1.Timer
//通过 time.After 模拟超时
func testTimerAfter(){
c := make(chan int)
go func() {
//time.Sleep(1 * time.Second)
time.Sleep(3 * time.Second)
<-c
}()
select {
case c <- 1:
fmt.Println("channel...")
case <-time.After(2 * time.Second): //阻塞两秒钟
close(c)
fmt.Println("timeout...")
}
}
//time.Stop 停止定时器 或 time.Reset 重置定时器
func testTimerReset(){
start := time.Now()
timer := time.AfterFunc(2*time.Second, func() {
fmt.Println("after func callback, elaspe:", time.Now().Sub(start))
})
//time.Sleep(1 * time.Second)
time.Sleep(3*time.Second)
// Reset 在 Timer 还未触发时返回 true;触发了或 Stop 了,返回 false
// Reset 会先调用 stopTimer 再调用 startTimer,类似于废弃之前的定时器,重新启动一个定时器。返回值和 Stop 一样。
if timer.Reset(3 * time.Second) {
fmt.Println("timer has not trigger!")
} else {
fmt.Println("timer had expired or stop!")
}
time.Sleep(10 * time.Second)
}
2.Tick
func testTickDemo() {
//定义一个1秒间隔的定时器
ticker := time.Tick(time.Second)
for i := range ticker {
fmt.Println(i)
}
}
3.定时器的实际应用
- github.com/jasonlvhit/gocron
- github.com/robfig/cron