[iProg] 一个例子，有助于大家学习channel，不多说，直接上代码！这个例子是定时检查【当前时间】和【lastHeartBeatTime】的时间段值，小于6秒输出“is alive” ，大于6秒输出程序结束！

gistfile1.txt

package main

import (
  "fmt"
	"time"
)

var lastHeartBeatTime time.Time
var checkChan chan bool
var checkoutChan chan bool
var out chan int

func main() {

	checkChan = make(chan bool)
	checkoutChan = make(chan bool)
	out = make(chan int)

	lastHeartBeatTime = time.Now()
	fmt.Println(lastHeartBeatTime.Format("2006-01-02 15:04:05"))
	fmt.Println()

	dd := time.NewTimer(time.Second * 1)
	<-dd.C

	go CheckTimeOut()

	d := time.NewTimer(time.Second * 1)
	<-d.C

	checkChan <- true
	<-out

}

func CheckTimeOut() {
	timeoutflag := 0
	var ticker *time.Ticker
	for {
		select {
		case ch := <-checkChan:
			if ch {
				go func() {
					ticker = time.NewTicker(time.Second)
					defer ticker.Stop()
					for t := range ticker.C {
						fmt.Println(t.Format("2006-01-02 15:04:05"))
						isTimeOut()
					}
				}()
			}

		case sh := <-checkoutChan:
			if sh {
				if ticker != nil {
					ticker.Stop()
					fmt.Println("timer stop")
					timeoutflag = 1
				}
			}
		}

		if timeoutflag == 1 {
			break
		}
	}
	fmt.Println("func end")
	out <- 1
}

func isTimeOut() {

	duration := time.Now().Sub(lastHeartBeatTime)
	if duration.Seconds() >= 6 {
		fmt.Println(duration, " ----- break Connection!")
		fmt.Println()
		checkoutChan <- true
	} else {
		fmt.Println(duration, " ----- is alive!")
		fmt.Println()
	}

}