go - 停止使用 'bufio.NewReader(os.Stdin)' 查找用户输入

Question

golang 和一般编程新手。我目前正在为学习任务编写一个小测验程序，但遇到了教程 Unresolved 问题，因为我有教程中未包含的功能。

代码如下:

func runQuestions(randomize bool) int {
tempqSlice := qSlice //Create temporary set of questions (Don't touch original)
if randomize { //If user has chosen to randomize the question order
    tempqSlice = shuffle(tempqSlice) //Randomize
}

var runningscore int

userinputchan := make(chan string) //Create return channel for user input
go getInput(userinputchan) //Constantly wait for user input

for num, question := range tempqSlice { //Iterate over each question
    fmt.Printf("Question %v:\t%v\n\t", num+1, question.GetQuestion())
    select {
    case <-time.After(5 * time.Second): //
        fmt.Println("-time up! next question-")
        continue
    case input := <-userinputchan:
        if question.GetAnswer() == input { //If the answer is correct
            runningscore++
            continue //Continue to next question
        }
    }

}
return runningscore

}

func getInput(returnchan chan<- string) {
for {
    reader := bufio.NewReader(os.Stdin) //Create reader
    input, _ := reader.ReadString('\n') //Read from
    returnchan <- strings.TrimSpace(input) //Trim the input and send it
}

}

因为问题的规范要求每个问题都有时间限制，所以我设置了一个“无尽的 for loop goroutine”运行，等待用户输入，然后在给出时发送。我的问题很简单:我想在测验结束后停止读者寻找输入，但由于'reader.ReadString('/n')' 已经在等待输入，我不知道如何。

Answer 1

I would like to stop the reader looking for input once the quiz is over

当读者在寻找输入时，您可以使用在其后台运行的 goroutine 来检查测验计时器是否已过期。

假设您的测验计时器是 30 秒。将计时器传递给 goroutine getInput并检查计时器是否到期。

var runningscore int
userinputchan := make(chan string) //Create return channel for user input
myTime := flag.Int("timer", 30, "time to complete the quiz")
timer := startTimer(myTime)
go getInput(userinputchan, timer) 

func startTimer(myTime *int) *time.Timer {
    return time.NewTimer(time.Duration(*myTime) * time.Second)
}

func getInput(returnchan chan<- string, timer *time.Timer) {
    for {
        reader := bufio.NewReader(os.Stdin)    //Create reader
        go checkTime(timer)                    
        input, _ := reader.ReadString('\n')    //Read from
        returnchan <- strings.TrimSpace(input) //Trim the input and send it
    }
}

func checkTime(timer *time.Timer) {
    <-timer.C
    fmt.Println("\nYour quiz is over!!!")
    // print the final score
    os.Exit(1)
}