输入字符串而不是整数时，停止控制台多次打印相同的消息

Question

在我的 CLI 程序中，我有这个功能，用户可以告诉我他们想要多少商品。因此，此输入应为整数。

我目前遇到一个问题，如果他们输入一个字符串，它会出错expected an integer，但随后还会再次打印该问题多次而不是一次。

例子：

How many Fruit Tea would you like to buy? qwe
expected integer
How many Fruit Tea would you like to buy? expected integer
How many Fruit Tea would you like to buy? expected integer
How many Fruit Tea would you like to buy?

以下是处理此功能的代码

for {
    fmt.Printf("How many %v would you like to buy? ", product.Name)
    _, err := fmt.Scan(&response)
    if err != nil {
        fmt.Println(err)
        continue
    }

    if ok, err := validResponse(response); ok {
        break
    } else {
        fmt.Println(err)
        continue
    }
}

我必须在这个循环中更改什么，以便它只重复一次问题？

Answer 1

如果可以，请将response 的类型从int 切换为string，然后使用包strconv（如strconv.Atoi()）解析输入字符串。我怀疑Scan 正在尝试将您输入的每个字符作为单独的 int 读取，每次都失败，并且每次都运行循环，直到所有字符都被消耗完。

例如

    for {
        var response string
        fmt.Printf("How many %v would you like to buy? ", product.Name)
        _, err := fmt.Scanln(&response)
        if err != nil { // probably don't need to check err from Scan()
            fmt.Println(err)
            continue
        }
        num, err := strconv.Atoi(response)
        if err != nil {
            fmt.Println("Enter an integer.")
            continue
        }

        if ok, err := validResponse(num); ok && err==nil {
            break
        } else {
            fmt.Println(err)
            continue
        }
    }