Go之time包用法

type Time struct {
// wall and ext encode the wall time seconds, wall time nanoseconds,
// and optional monotonic clock reading in nanoseconds.
//
// From high to low bit position, wall encodes a 1-bit flag (hasMonotonic),
// a 33-bit seconds field, and a 30-bit wall time nanoseconds field.
// The nanoseconds field is in the range [0, 999999999].
// If the hasMonotonic bit is 0, then the 33-bit field must be zero
// and the full signed 64-bit wall seconds since Jan 1 year 1 is stored in ext.
// If the hasMonotonic bit is 1, then the 33-bit field holds a 33-bit
// unsigned wall seconds since Jan 1 year 1885, and ext holds a
// signed 64-bit monotonic clock reading, nanoseconds since process start.
wall uint64
ext  int64

    // loc specifies the Location that should be used to
    // determine the minute, hour, month, day, and year
    // that correspond to this Time.
    // The nil location means UTC.
    // All UTC times are represented with loc==nil, never loc==&utcLoc.
    loc *Location
}

package main

import (
    "fmt"
    "time"
)

func main() {
    t:=time.Now()
    fmt.Println(t)//获取当前时间2021-09-23 10:55:44.831571 +0800 CST m=+0.000090412
    fmt.Println(t.Unix())//获取当前时间时间戳 1632366278
    fmt.Println(t.UnixMilli())//获取当前时间毫秒 1632366278605
    fmt.Println(t.UnixMicro())//获取当前时间微秒 1632366278605122
    fmt.Println(t.UnixNano())//获取当前时间时纳秒 1632366278605122000
    fmt.Println(t.Hour())//获取当前小时 10
    fmt.Println(t.Day())//获取当前天 23
    fmt.Println(t.Weekday())//获取当前周Thursday
    fmt.Println(t.ISOWeek())//获取当前周2021 38

    //格式化当前时间表示
    fmt.Println(t.String())//字符型
    fmt.Println(t.Format("2006-01-02 15:04:05"))//2021-09-23 11:12:42
    fmt.Println(t.Format("2006-01-02"))//2021-09-23
    fmt.Println(t.Format("15:04:05"))//11:12:42

    //指定时间戳转换
    fmt.Println(time.Unix(1632366278, 0).Format("2006-01-02 15:04:05"))//2021-09-23 11:04:38
    //指定时间转时间戳
    tm2, _ := time.Parse("2006-01-02 15:04:05", "2021-09-23 11:04:38")
    fmt.Println( tm2.Unix())//1632395078

    //"2021-09-08T08:18:46+08:00" 转2021-09-08 08:18:46
    t, _= time.Parse(time.RFC3339, "2021-09-08T08:18:46+08:00")
    fmt.Println(t.Format("2006-01-02 15:04:05"))
    //2021-09-07T17:01:34.182659088Z 转2021-09-07 17:01:34
    t, _= time.Parse(time.RFC3339Nano, "2021-09-07T17:01:34.182659088Z")
    fmt.Println(t.Format("2006-01-02 15:04:05"))
    //其他格式类似可参考

    //ANSIC       = "Mon Jan _2 15:04:05 2006"
    //UnixDate    = "Mon Jan _2 15:04:05 MST 2006"
    //RubyDate    = "Mon Jan 02 15:04:05 -0700 2006"
    //RFC822      = "02 Jan 06 15:04 MST"
    //RFC822Z     = "02 Jan 06 15:04 -0700" // 使用数字表示时区的RFC822
    //RFC850      = "Monday, 02-Jan-06 15:04:05 MST"
    //RFC1123     = "Mon, 02 Jan 2006 15:04:05 MST"
    //RFC1123Z    = "Mon, 02 Jan 2006 15:04:05 -0700" // 使用数字表示时区的RFC1123
    //RFC3339     = "2006-01-02T15:04:05Z07:00"
    //RFC3339Nano = "2006-01-02T15:04:05.999999999Z07:00"
    //Kitchen     = "3:04PM"
    //// 方便的时间戳
    //Stamp      = "Jan _2 15:04:05"
    //StampMilli = "Jan _2 15:04:05.000"
    //StampMicro = "Jan _2 15:04:05.000000"
    //StampNano  = "Jan _2 15:04:05.000000000"

     //设置时区 Location
    //默认UTC
    loc, _ := time.LoadLocation("")
    // 服务器设定的时区，一般为CST
    //loc, _ := time.LoadLocation("Local")
    //loc, _ := time.LoadLocation("Asia/Shanghai")
    t.In(loc).Format("2006-01-02 15:04:05");

    //1.5s后
    now := time.Now()
    tp, _ := time.ParseDuration("1.5s")
    fmt.Println(tp,tp.Truncate(1000), tp.Seconds(), tp.Nanoseconds())
    m1 := now.Add(tp)
    fmt.Println(m1)//2021-09-23 14:30:42.006213 +0800 CST m=+1.500352171

    //1个小时前
    tp, _ = time.ParseDuration("-1h")

    m1 = now.Add(tp)
    fmt.Println(m1)//2021-09-23 13:30:40.506213 +0800 CST m=-3599.999647829
    //休眠时间
    //time.Sleep(time.Duration(10) * time.Second)

    // func After(d Duration) <-chan Time  非阻塞,可用于延迟
    //time.After(time.Duration(10) * time.Second)



    // func Since(t Time) Duration 两个时间点的间隔
    start := time.Now()
    fmt.Println(time.Since(start))   // 等价于 Now().Sub(t)， 可用来计算一段业务的消耗时间

    //func Until(t Time) Duration     //  等价于 t.Sub(Now())，t与当前时间的间隔


    time3 := "2021-03-20 08:50:29"
    time4 := "2021-03-20 08:50:29"
    //先把时间字符串格式化成相同的时间类型
    t3, _ := time.Parse("2006-01-02 15:04:05", time3)
    t4, _ := time.Parse("2006-01-02 15:04:05", time4)

    fmt.Println(t3.Equal(t4)) //true


    now = time.Now()
    //Ticker 类型包含一个 channel，有时我们会遇到每隔一段时间执行的业务(比如设置心跳时间等)，就可以用它来处理，这是一个重复的过程

    // 无法取消
    //tick := time.Tick(1 * time.Minute)
    //for _ = range tick {
    //    // do something
    //}
    //NewTicker返回一个新的Ticker，该Ticker包含一个通道字段，并会每隔时间段d就向该通道发送当时的时间。它会调整时间间隔或者丢弃tick信息以适应反应慢的接收者。如果d<=0会panic。关闭该Ticker可以释放相关资源。
    // 可通过调用ticker.Stop取消
    //创建一个周期性的定时器
    //设置定时器为3秒
    timer := time.NewTimer(3 * time.Second)
    fmt.Println("当前时间为:", time.Now())

    t = <-timer.C //从定时器拿数据
    fmt.Println("当前时间为:", t)
    timer.Stop()//停止
    
}