Go日期

package main
import (
	"fmt"
	"time"
)

func main() {
	//看看日期和时间相关函数和方法使用
	//1. 获取当前时间
	now := time.Now()
	fmt.Printf("now=%v now type=%T\n", now, now) //now=2020-01-20 03:43:53.1244468 +0800 CST m=+0.002990201 now type=time.Time

	//2.通过now可以获取到年月日，时分秒
	fmt.Printf("年=%v\n", now.Year()) //年=2020
	fmt.Printf("月=%v\n", now.Month()) //月=January
	fmt.Printf("月=%v\n", int(now.Month())) //月=1
	fmt.Printf("日=%v\n", now.Day()) //日=20
	fmt.Printf("分=%v\n", now.Minute()) //分=43
	fmt.Printf("秒=%v\n", now.Second()) //秒=53

	//格式化日期时间

	fmt.Printf("当前年月日 %d-%d-%d %d:%d:%d \n", now.Year(), //当前年月日 2020-1-20 3:45:48 
		now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())

	dateStr := fmt.Sprintf("当前年月日 %d-%d-%d %d:%d:%d \n", now.Year(), //dateStr=当前年月日 2020-1-20 3:45:48 
		now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())

	fmt.Printf("dateStr=%v\n", dateStr)

	//格式化日期时间的第二种方式
	fmt.Printf(now.Format("2006-01-02 15:04:05")) //2020-01-20 03:45:48
	fmt.Println() 
	fmt.Printf(now.Format("2006-01-02")) //2020-01-20
	fmt.Println()
	fmt.Printf(now.Format("15:04:05")) //03:45:48
	fmt.Println()

	fmt.Printf(now.Format("2006")) //2020
	fmt.Println()


	//需求，每隔1秒中打印一个数字，打印到100时就退出
	//需求2: 每隔0.1秒中打印一个数字，打印到100时就退出
	// i := 0
	// for {
	// 	i++
	// 	fmt.Println(i)
	// 	//休眠
	// 	//time.Sleep(time.Second)
	// 	time.Sleep(time.Millisecond * 100)
	// 	if i == 100 {
	// 		break
	// 	}
	// }

	//Unix和UnixNano的使用
	fmt.Printf("unix时间戳=%v unixnano时间戳=%v\n", now.Unix(), now.UnixNano())
	//unix时间戳=1579463148 unixnano时间戳=1579463148802059600

}