关于golang:Go之time包用法

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time 包提供了工夫的显示和测量用的函数。日历的计算采纳的是公历。
time 类型

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
}

time 能够准确到纳秒
示例

package main

import (
    "fmt"
    "time"
)

func main() {t:=time.Now()
    fmt.Println(t)// 获取以后工夫 2021-09-23 10:55:44.831571 +0800 CST m=+0.000090412
    fmt.Println(t.Unix())// 获取以后工夫工夫戳 1632366278
    fmt.Println(t.UnixMilli())// 获取以后工夫毫秒 1632366278605
    fmt.Println(t.UnixMicro())// 获取以后工夫微秒 1632366278605122
    fmt.Println(t.UnixNano())// 获取以后工夫时纳秒 1632366278605122000
    fmt.Println(t.Hour())// 获取以后小时 10
    fmt.Println(t.Day())// 获取以后天 23
    fmt.Println(t.Weekday())// 获取以后周 Thursday
    fmt.Println(t.ISOWeek())// 获取以后周 2021 38

    // 格式化以后工夫示意
    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

    // 指定工夫戳转换
    fmt.Println(time.Unix(1632366278, 0).Format("2006-01-02 15:04:05"))//2021-09-23 11:04:38
    // 指定工夫转工夫戳
    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"))
    // 其余格局相似可参考

    //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" // 应用数字示意时区的 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" // 应用数字示意时区的 RFC1123
    //RFC3339     = "2006-01-02T15:04:05Z07:00"
    //RFC3339Nano = "2006-01-02T15:04:05.999999999Z07:00"
    //Kitchen     = "3:04PM"
    //// 不便的工夫戳
    //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，个别为 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
    // 休眠工夫
    //time.Sleep(time.Duration(10) * time.Second)

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



    // func Since(t Time) Duration 两个工夫点的距离
    start := time.Now()
    fmt.Println(time.Since(start))   // 等价于 Now().Sub(t)，可用来计算一段业务的耗费工夫

    //func Until(t Time) Duration     //  等价于 t.Sub(Now())，t 与以后工夫的距离


    time3 := "2021-03-20 08:50:29"
    time4 := "2021-03-20 08:50:29"
    // 先把工夫字符串格式化成雷同的工夫类型
    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 类型蕴含一个 channel，有时咱们会遇到每隔一段时间执行的业务(比方设置心跳工夫等)，就能够用它来解决，这是一个反复的过程

    // 无奈勾销
    //tick := time.Tick(1 * time.Minute)
    //for _ = range tick {
    //    // do something
    //}
    //NewTicker 返回一个新的 Ticker，该 Ticker 蕴含一个通道字段，并会每隔时间段 d 就向该通道发送过后的工夫。它会调整工夫距离或者抛弃 tick 信息以适应反馈慢的接收者。如果 d <= 0 会 panic。敞开该 Ticker 能够开释相干资源。// 可通过调用 ticker.Stop 勾销
    // 创立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("以后工夫为:", time.Now())

    t = <-timer.C // 从定时器拿数据
    fmt.Println("以后工夫为:", t)
    timer.Stop()// 进行}

https://studygolang.com/pkgdoc

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