func SelectTest() {
 i := 0
 for {
 select {
 case <-time.After(time.Second * time.Duration(2)):
 i++
 if i == 5 {
 fmt.Println("跳出for循环")
 }
 }
 fmt.Println("for循环内 i=", i)
 }
 fmt.Println("for循环外")
}

func SelectTest() {
 i := 0
Loop:
 for {
 select {
 case <-time.After(time.Second * time.Duration(2)):
 i++
 if i == 5 {
 fmt.Println("跳出for循环")
 break Loop
 }
 }
 fmt.Println("for循环内 i=", i)
 }
 fmt.Println("for循环外")
}

func SelectTest() {
 i := 0
 for {
 select {
 case <-time.After(time.Second * time.Duration(2)):
 i++
 if i == 5 {
 fmt.Println("跳出for循环")
 goto Loop
 }
 }
 fmt.Println("for循环内 i=", i)
 }
Loop:
 fmt.Println("for循环外")
}

func testSelectFor(chExit chan bool){
 for {
 select {
 case v, ok := <-chExit:
 if !ok {
 fmt.Println("close channel 1", v)
 break
 }
 fmt.Println("ch1 val =", v)
 }
 }
 fmt.Println("exit testSelectFor")
}

//尝试2 select for 跳出循环
c := make(chan bool)
go testSelectFor(c)
 
c <- true
c <- false
close(c)
 
time.Sleep(time.Duration(2) * time.Second)

...
close channel 1 false
close channel 1 false
close channel 1 false
close channel 1 false
...

func testSelectFor2(chExit chan bool){
 EXIT:
 for {
 select {
 case v, ok := <-chExit:
 if !ok {
 fmt.Println("close channel 2", v)
 break EXIT//goto EXIT2
 }
 
 fmt.Println("ch2 val =", v)
 }
 }
 //EXIT2:
 fmt.Println("exit testSelectFor2")
}

ch2 val = true
ch2 val = false
close channel 2 false
exit testSelectFor2