Golang 在另一个 for 循环中退出 bufio for 循环

Question

我有一个初始循环，它不断询问用户问题，直到用户键入 q 退出。

func main() {
 scanner := bufio.NewScanner(os.Stdin)
 quit := false
 var city string
 var anything string
 for quit == false {    
     fmt.Println("Enter a city name")
     for scanner.Scan(){
         city= scanner.Text()
         fmt.Printf("q to quit (Anything else to continue): ")
         anything = scanner.Text()
     }
     if anything == "q" {
         fmt.Println(city)
         quit = true
     }
 }
}

我正在努力弄清楚的是如何退出扫描仪的嵌套 for 循环并继续初始 for 循环，直到用户输入 q。现在，它不会退出第二个循环，所以它总是提示“q to quit ...”，当我休息时，它会退出两个循环。

知道我应该如何解决这个问题吗？

Answer 1

很难准确地说出您想要什么，因为您没有向我们提供样本输入和输出。也许，根据您的代码，是这样的:

package main

import (
    "bufio"
    "fmt"
    "os"
)

func main() {
    var cities []string
    scanner := bufio.NewScanner(os.Stdin)
    for {
        fmt.Println("Enter a city name")
        if !scanner.Scan() {
            break
        }
        city := scanner.Text()
        if len(city) > 0 {
            cities = append(cities, city)
        }
        fmt.Printf("q to quit (Anything else to continue): ")
        if !scanner.Scan() || scanner.Text() == "q" {
            break
        }
    }
    if err := scanner.Err(); err != nil {
        fmt.Fprintln(os.Stderr, err)
    }
    fmt.Printf("%q\n", cities)
}

输出:

Enter a city name
Los Angeles
q to quit (Anything else to continue): 
Enter a city name
London
q to quit (Anything else to continue): 
Enter a city name
Delhi
q to quit (Anything else to continue): q
["Los Angeles" "London" "Delhi"]