Tips of Tim pkg

01 time_pkg.go

package main

import (
	"fmt"
	"time"
	"strconv"
)

func main() {
	fmt.Println("----- Basic usage -----")
	now := time.Now()
	fmt.Println("Now()        : " + now.String())
	time1 := time.Date(2018, 10, 15, 16, 48, 32, 12345, time.Local)
	fmt.Println("Date()       : " + time1.String())
	fmt.Println()
	
	fmt.Println("----- Functions -----")
	fmt.Println("Year()       : " + strconv.Itoa(now.Year()))
	fmt.Println("Month()      : " + now.Month().String())
	fmt.Println("int(now.Month()) : " + strconv.Itoa(int(now.Month())))
	fmt.Println("Day()        : " + strconv.Itoa(now.Day()))
	fmt.Println("Hour()       : " + strconv.Itoa(now.Hour()))
	fmt.Println("Minute()     : " + strconv.Itoa(now.Minute()))
	fmt.Println("Second()     : " + strconv.Itoa(now.Second()))
	fmt.Println("Nanosecond() : " + strconv.Itoa(now.Nanosecond()))
	fmt.Println("Weekday()    : " + now.Weekday().String())
	fmt.Println("int(Weekday()) : " + strconv.Itoa(int(now.Weekday())))
	fmt.Println("Unix()       : " + strconv.FormatInt(now.Unix(), 10))
	fmt.Println("UnixNano()   : " + strconv.FormatInt(now.UnixNano(), 10))
	iso_year, iso_week := now.ISOWeek()
	fmt.Println("ISOWeek() year : " + strconv.Itoa(iso_year))
	fmt.Println("ISOWeek() week : " + strconv.Itoa(iso_week))
	fmt.Println()
	
	fmt.Println("----- Simple Functions -----")
	fmt.Println("Date()  Clock()")
	year, month, day := now.Date()
	hour, min, sec   := now.Clock()
	fmt.Println(year)
	fmt.Println(int(month))
	fmt.Println(day)
	fmt.Println(hour)
	fmt.Println(min)
	fmt.Println(sec)
	fmt.Println()
	fmt.Println("YearDay()    : " + strconv.Itoa(now.YearDay()))
	fmt.Println("UTC()        : " + now.UTC().String())
	fmt.Println("Local()      : " + now.Local().String())
	zoneName, zoneOffset := now.Zone()
	fmt.Println("Zone() (name,offset) : " + "( " + zoneName + " , " + strconv.Itoa(zoneOffset) + " )")
	fmt.Println()

	fmt.Println("----- Add -----")
	fmt.Println("Now()           : " + now.String())
	now = now.Add(time.Duration(-1) * time.Hour)
	fmt.Println("time 1 hour ago : " + now.String())
	fmt.Println()
	
	fmt.Println("----- Parse() Format()-----")
	var timeParse01 = time.Time{}
	timeParse01, _  = time.Parse("2006/01/02 15:04:05 (MST)", "2018/12/21 13:45:38 (JST)")
	fmt.Println("Parse()          : " + timeParse01.String())
	fmt.Println("Format(ANSIC)    : " + timeParse01.Format(time.ANSIC))
	fmt.Println("Format(RFC1123Z) : " + timeParse01.Format(time.RFC1123Z))
	fmt.Println()

	fmt.Println("----- ParseDuration() -----")
	duration, _ := time.ParseDuration("2h35m10s")
	fmt.Println("Duration String      : " + duration.String())
	fmt.Println("Duration in minutes  : " + strconv.FormatFloat(duration.Minutes(), 'f', 0, 64))
	fmt.Println("Duration in seconds  : " + strconv.FormatFloat(duration.Seconds(), 'f', 0, 64))
	fmt.Println()

	fmt.Println("----- Sub() Since() Until() -----")
	time01 := time.Date(2018, 10, 10, 15,  0,  0, 0, time.Local)
	time02 := time.Date(2018, 10, 25, 15, 30, 10, 0, time.Local)
	fmt.Println("time01   : " + time01.String())
	fmt.Println("time02   : " + time02.String())
	time01Subtime02 := time01.Sub(time02)
	time02Subtime01 := time02.Sub(time01)
	fmt.Println("time01.Sub(time02)   : " + time01Subtime02.String())
	fmt.Println("time02.Sub(time01)   : " + time02Subtime01.String())
	fmt.Println()
	time03 := time.Date(2018, 12, 10, 0, 0, 0, 0, time.Local)
	time04 := time.Date(2018, 12, 25, 0, 0, 0, 0, time.Local)
	fmt.Println("Now()    : " + now.String())
	fmt.Println("time03   : " + time03.String())
	fmt.Println("time04   : " + time04.String())
	fmt.Println("time.Since(time03)   : " + time.Since(time03).String())
	fmt.Println("time.Until(time04)   : " + time.Until(time04).String())
	fmt.Println()
	
	fmt.Println("----- After() Before() -----")
	date11m := time.Date(2018, 11, 1, 0, 0, 0, 0, time.Local)
	date12m := time.Date(2018, 12, 1, 0, 0, 0, 0, time.Local)
	
	fmt.Println(date11m)
	fmt.Println(date12m)
	isDate11mAfterDate12m := date11m.After(date12m)
	isDate12mAfterDate11m := date12m.After(date11m)
	fmt.Printf("date11m.After(date12m)  = %v\n", isDate11mAfterDate12m)
	fmt.Printf("date12m.After(date11m)  = %v\n", isDate12mAfterDate11m)
	
	isDate11mBeforeDate12m := date11m.Before(date12m)
	isDate12mBeforeDate11m := date12m.Before(date11m)
	fmt.Printf("date11m.Before(date12m) = %v\n", isDate11mBeforeDate12m)
	fmt.Printf("date12m.Before(date11m) = %v\n", isDate12mBeforeDate11m)
	fmt.Println()
	
	fmt.Println("----- Equal() -----")
	secondsEastOfUTC := int((8 * time.Hour).Seconds())
	beijing := time.FixedZone("Beijing Time", secondsEastOfUTC)
	timeBeijin := time.Date(2018, 2, 1, 20, 15, 45, 0, beijing)
	timeUtc    := time.Date(2018, 2, 1, 12, 15, 45, 0, time.UTC)
	fmt.Println(timeBeijin)
	fmt.Println(timeUtc)
	datesEqualUsingEqualOperator := timeBeijin == timeUtc
	datesEqualUsingFunction      := timeBeijin.Equal(timeUtc)
	fmt.Printf("datesEqualUsingEqualOperator = %v\n", datesEqualUsingEqualOperator)
	fmt.Printf("datesEqualUsingFunction = %v\n", datesEqualUsingFunction)
	fmt.Println()

	fmt.Println("----- Round() Truncate() -----")
	time10    := time.Date(2018, 12, 10, 14, 15, 45, 987654321, time.Local)
	fmt.Println("time10                      : " + time10.String())
	fmt.Println("time10.Round(time.Hour)     : " + time10.Round(time.Hour).String())
	fmt.Println("time10.Round(time.Minute)   : " + time10.Round(time.Minute).String())
	fmt.Println("time10.Round(time.Second)   : " + time10.Round(time.Second).String())
	fmt.Println("time10.Truncate(time.Hour)  : " + time10.Truncate(time.Hour).String())
	fmt.Println("time10.Truncate(time.Minute): " + time10.Truncate(time.Minute).String())
	fmt.Println("time10.Truncate(time.Second): " + time10.Truncate(time.Second).String())
	fmt.Println()

	fmt.Println("----- IsZero() -----")
	timeRight, _  := time.Parse("2006/01/02 15:04", "2018/12/21 13:45")
	timeFail, _   := time.Parse("2006/01/02 15:04", "2018/12/21 hoge 13:45")
	fmt.Println("timeRight   : " + timeRight.String())
	fmt.Println("timeFail    : " + timeFail.String())
	fmt.Println("timeRight.IsZero()   : " + strconv.FormatBool(timeRight.IsZero()))
	fmt.Println("timeFail.IsZero()    : " + strconv.FormatBool(timeFail.IsZero()))
	fmt.Println()
}

02 output.txt

----- Basic usage -----
Now()        : 2018-12-21 18:39:05.7407367 +0900 JST m=+0.026072201
Date()       : 2018-10-15 16:48:32.000012345 +0900 JST

----- Functions -----
Year()       : 2018
Month()      : December
int(now.Month()) : 12
Day()        : 21
Hour()       : 18
Minute()     : 39
Second()     : 5
Nanosecond() : 740736700
Weekday()    : Friday
int(Weekday()) : 5
Unix()       : 1545385145
UnixNano()   : 1545385145740736700
ISOWeek() year : 2018
ISOWeek() week : 51

----- Simple Functions -----
Date()  Clock()
2018
12
21
18
39
5

YearDay()    : 355
UTC()        : 2018-12-21 09:39:05.7407367 +0000 UTC
Local()      : 2018-12-21 18:39:05.7407367 +0900 JST
Zone() (name,offset) : ( JST , 32400 )

----- Add -----
Now()           : 2018-12-21 18:39:05.7407367 +0900 JST m=+0.026072201
time 1 hour ago : 2018-12-21 17:39:05.7407367 +0900 JST m=-3599.973927799

----- Parse() Format()-----
Parse()          : 2018-12-21 13:45:38 +0900 JST
Format(ANSIC)    : Fri Dec 21 13:45:38 2018
Format(RFC1123Z) : Fri, 21 Dec 2018 13:45:38 +0900

----- ParseDuration() -----
Duration String      : 2h35m10s
Duration in minutes  : 155
Duration in seconds  : 9310

----- Sub() Since() Until() -----
time01   : 2018-10-10 15:00:00 +0900 JST
time02   : 2018-10-25 15:30:10 +0900 JST
time01.Sub(time02)   : -360h30m10s
time02.Sub(time01)   : 360h30m10s

Now()    : 2018-12-21 17:39:05.7407367 +0900 JST m=-3599.973927799
time03   : 2018-12-10 00:00:00 +0900 JST
time04   : 2018-12-25 00:00:00 +0900 JST
time.Since(time03)   : 282h39m5.8604157s
time.Until(time04)   : 77h20m54.1395843s

----- After() Before() -----
2018-11-01 00:00:00 +0900 JST
2018-12-01 00:00:00 +0900 JST
date11m.After(date12m)  = false
date12m.After(date11m)  = true
date11m.Before(date12m) = true
date12m.Before(date11m) = false

----- Equal() -----
2018-02-01 20:15:45 +0800 Beijing Time
2018-02-01 12:15:45 +0000 UTC
datesEqualUsingEqualOperator = false
datesEqualUsingFunction = true

----- Round() Truncate() -----
time10                      : 2018-12-10 14:15:45.987654321 +0900 JST
time10.Round(time.Hour)     : 2018-12-10 14:00:00 +0900 JST
time10.Round(time.Minute)   : 2018-12-10 14:16:00 +0900 JST
time10.Round(time.Second)   : 2018-12-10 14:15:46 +0900 JST
time10.Truncate(time.Hour)  : 2018-12-10 14:00:00 +0900 JST
time10.Truncate(time.Minute): 2018-12-10 14:15:00 +0900 JST
time10.Truncate(time.Second): 2018-12-10 14:15:45 +0900 JST

----- IsZero() -----
timeRight   : 2018-12-21 13:45:00 +0000 UTC
timeFail    : 0001-01-01 00:00:00 +0000 UTC
timeRight.IsZero()   : false
timeFail.IsZero()    : true