Question

我刚刚进入编程，尝试了所有的东西，但第一个其他的总是无效的，它的probs真的很明显，但无法弄明白

if (answer == (num1 * num2)) 
{
    int responsegen = numbergenerator.Next (1, 4);

    switch (responsegen)  
    {

        case 1:
            Console.WriteLine ("Congrats! You're a natrual");
            break;

        case 2:
            Console.WriteLine ("Correct, Mini Einstein maybe?");

        default :
            Console.WriteLine ("Right answer , are you cheating?");

} 
else // this one right here 
{
    int diff = (answer - (num1 * num2));

    if (diff == 1) 
    {
        Console.WriteLine ("OHH so close you were only of by one number!");
    }

    if (diff <=10) 
    {
        Console.WriteLine ("Incorrect but you were close, only of by " + diff + "better luck next time!");                  
    }
}

Answer 1

你正试图这样做：

switch (responsegen)  {
    //...
} else
//...

您无法使用switch关注else语句。 switch在其案例列表中使用default子句作为逻辑“else”。（你已经在使用它，所以你所做的甚至在语义上都没有意义。）

也许您打算将else附加到前一个if块？：

if (answer == (num1 * num2)) {
    //...
    switch (responsegen)  {
        //...
    } // <-- first close the switch block
} else // <-- then continue the if block
//...

当你继续学习编程时，你会发现使用空格的一致和干净的使用（回车，缩进等）会使这个很多更容易找到。

Answer 2

你错过了一个大括号和几句break;陈述：

if (answer == (num1 * num2)) 
{
    int responsegen = numbergenerator.Next(1, 4);

    switch (responsegen)  
    {
        case 1:
            Console.WriteLine("Congrats! You're a natural");
            break;

        case 2:
            Console.WriteLine("Correct, Mini Einstein maybe?");
            break; // <-- you need a break; here...

        default:
            Console.WriteLine("Right answer, are you cheating?");
            break; // <-- ...and here.
    } // <-- add a brace here
} 
else
{
    int diff = answer - (num1 * num2);

    if (diff == 1) 
    {
        Console.WriteLine("OHH so close, you were only off by one number!");
    }
    else if (diff <= 10) 
    {
        Console.WriteLine("Incorrect but you were close - only off by " + diff + ". Better luck next time!");                  
    }
}

我已经更正了你的拼写和语法，作为奖励。

Answer 3

你缺少2个休息语句和大括号。

工作代码：

        if (answer == (num1*num2))
        {
            int responsegen = numbergenerator.Next(1, 4);

            switch (responsegen)
            {

                case 1:
                    Console.WriteLine("Congrats! You're a natrual");
                    break;

                case 2:
                    Console.WriteLine("Correct, Mini Einstein maybe?");
                    break;

                default:
                    Console.WriteLine("Right answer , are you cheating?");
                    break;
            }
        }
        else // this mofo right here help!!!! 
        {
            int diff = (answer - (num1*num2));

            if (diff == 1)
            {
                Console.WriteLine("OHH so close you were only of by one number!");
            }

            if (diff <= 10)
            {
                Console.WriteLine("Incorrect but you were close, only of by " + diff + "better luck next time!");
            }
        }

此外，即使一旦编译，if语句也有点怀疑......如果'diff'为1，那么你将得到两条写入控制台的消息......

表达式“else”无效

3 个答案: