Golang当中的定时器实例详解

package main

import (
	"fmt"
	"time"
)
func main() {
	myTimer := time.NewTimer(time.Second * 3) //初始化定时器
	var i = 0
	for {
		select {
		case <-myTimer.C:
			i++
			fmt.Printf("the counter is%d", i)
			myTimer.Reset(time.Second * 3) //注意需要重新设置
		}
	}
	myTimer.Stop() //不在使用需要将其停止
}

func NewTimer(d Duration) *Timer {
    c := make(chan Time, 1)
    t := &Timer{
        C: c,  // 信道
        r: runtimeTimer{
            when: when(d),  // 触发时间
            f:    sendTime, // 时间到了之后的调用函数
            arg:  c,        // 调用sendTime时的入参
        },
    }
    startTimer(&t.r)  // 把定时器的r字段放入由定时器维护协程维护的堆中
    return t
}　

func sendTime(c interface{}, seq uintptr) {
    // Non-blocking send of time on c.
    // Used in NewTimer, it cannot block anyway (buffer).
    // Used in NewTicker, dropping sends on the floor is
    // the desired behavior when the reader gets behind,
    // because the sends are periodic.
    select {
    case c.(chan Time) <- Now():  //时间到了之后把当前时间放入信道中
    default:
    }
}　

import (
	"fmt"
	"time"
)

func main() {
	f := func() {
		fmt.Println("the func is call after 3 second")
	}
	myTime := time.AfterFunc(time.Second*3, f)

	defer myTime.Stop() //定时器不用了需要关闭
	time.Sleep(time.Second * 4)
}

package main

import (
	"fmt"
	"time"
)

func main() {
	mytick := time.NewTicker(time.Second * 2)
	defer mytick.Stop() //定时器不用了需要关闭
	done := make(chan struct{})
	go func() {
		for {
			time.Sleep(time.Second * 10)
			done <- struct{}{}
		}
	}()
	for {
		select {
		case <-done:
			fmt.Println("done!!!!")
			return
		case t := <-mytick.C:
			fmt.Printf("the curtime is %v\n", t)
		}
	}

}

package main
import (
	"fmt"
	"time"
)
func main() {
	var count int
	for {
		select {
		case <-time.Tick(time.Second * 1):
			fmt.Println("case1")
			count++
			fmt.Println("count--->", count)
		case <-time.Tick(time.Second * 2):
			fmt.Println("case2")
			count++
			fmt.Println("count--->", count)
		}
	}
}

func Tick(d Duration) <-chan Time {
	if d <= 0 {
		return nil
	}
	return NewTicker(d).C
}