gobyexample/time/time.go

package time

import (
	"fmt"
	"time"
)

var f = fmt.Println

func epoch() {
	now := time.Now().UTC()

	f("Epoch seconds:", now.Unix())
	f("Epoch milli:", now.UnixMilli())
	f("Epoch nano:", now.UnixNano())

	f("Custom time from epoch:", time.Unix(now.Unix(), 0))
	f("Custom time from epoch:", time.Unix(0, now.UnixNano()))
}

func Time() {
	now := time.Now().UTC()
	f(now)

	xmasTime := time.Date(2023, 12, 25, 9, 0, 0, 0, time.UTC)
	f("XMAS =>", xmasTime)

	f("Year:", xmasTime.Year())
	f("Month:", xmasTime.Month())
	f("Day:", xmasTime.Day())
	f("Hour:", xmasTime.Hour())
	f("Minute:", xmasTime.Minute())
	f("Second:", xmasTime.Second())
	f("Nanosecond:", xmasTime.Nanosecond())
	f("Weekday:", xmasTime.Weekday())

	f("Is Xmas before now?", xmasTime.Before(now))
	f("Is Xmas after now?", xmasTime.After(now))
	f("Is Xmas same as now?", xmasTime.Equal(now))

	diff := now.Sub(xmasTime)
	f(diff)

	f(diff.Hours())
	f(diff.Minutes())
	f(diff.Seconds())
	f(diff.Nanoseconds())

	f(xmasTime.Add(diff))
	f(now.Add(-diff))

	epoch()
	timeFormatting()
}

func timeFormatting() {
	now := time.Now()
	t1, _ := time.Parse(
		time.RFC3339,
		"2023-12-25T10:00:00+05:30",
	)
	f(t1)

	// Example string should match the datetime: Monday January 02 2006 15:04:05
	// (this resembles month:1 day:2 hour:3 minute:4 seconds:5 year:6)
	f("Custom format:", now.Format("2006/1/2"))
	f("Custom format:", now.Format("Monday, 02 Jan"))
	f("Custom format:", t1.Format("Monday, _2 Jan"))
	f("Custom format:", t1.Format("Monday, 2/01/2006"))
}