code
package main
import (
"fmt"
"time"
)
func chanTest(ch chan int) {
for { //select外层需要循环
select {
case value, ok := <-ch:
fmt.Println(value, ok, time.Now())
if ok == false {
fmt.Println("chan已经关闭", time.Now()) //select要自己判断退出,如果是for..range 形式,在读取完了关闭的chanel后,退出循环
return
}
default:
fmt.Println("chan 空了", time.Now())
time.Sleep(time.Second * 5) //分支的处理会阻塞整个select
}
}
}
func main() {
var ch = make(chan int, 100)
go chanTest(ch)
ch <- 1
ch <- 2
time.Sleep(time.Second * 2)
ch <- 3
ch <- 4
time.Sleep(time.Second)
close(ch)
for {
time.Sleep(time.Second)
}
}
需要注意的是,select的 defalut会丢弃数据,chan已满的情况,入chan的数据会被丢弃
引用
https://blog.csdn.net/x356982611/article/details/80506140