Question

所以，我对整个C＃语言都不熟悉，有人要求我们将简单的if if转换为开关。这就是我所知道的。这是对的吗？如果没有，你能告诉我问题在哪里吗？还是缺少什么？这里唯一的问题是开关盒的输出没有出现。

    static void Main(string[] args)
    {

        Console.Write("Enter Name: ");
        string studname = Console.ReadLine();
        Console.Write("Enter Age: ");
        string age = Console.ReadLine();
        Console.Write("Enter Year Level: ");
        int level = int.Parse(Console.ReadLine());
        Console.Write("Enter Course: ");
        string course = Console.ReadLine();
        Console.Write("Enter Score 1: ");
        int num1 = int.Parse(Console.ReadLine());
        Console.Write("Enter Score 2: ");
        int num2 = int.Parse(Console.ReadLine());
        Console.Write("Enter Score 3: ");
        int num3 = int.Parse(Console.ReadLine());
        int total = num1 + num2 + num3;
        int ave = (num1 + num2 + num3) / 3;
        int rate = ave;




        Console.WriteLine("");
        Console.WriteLine("");
        Console.WriteLine("");
        Console.Write("Student Name: " + studname);
        Console.WriteLine("");
        Console.Write("Student Age: " + age);
        Console.WriteLine("");
        Console.Write("Student Year Level: " + level);
        Console.WriteLine("");
        Console.Write("Student Course: " + course);
        Console.WriteLine("");
        Console.Write("Score 1: " + num1);
        Console.WriteLine("");
        Console.Write("Score 2: " + num2);
        Console.WriteLine("");
        Console.Write("Score 3: " + num3);
        Console.WriteLine("");
        Console.Write("Total_Score= " + total);
        Console.WriteLine("");
        Console.Write("Total_Average= " + ave);


        switch (rate)
        {
            case 1:
                if (rate < 100 && rate > 90)

                Console.Write("Rate = 1.00");
                Console.WriteLine("");
                Console.Write("Hi! " + studname + "you Passed");
                Console.WriteLine("");
               break;


            case 2:
                if (rate < 89 && rate > 85)

                    Console.Write("Rate = 1.00");
                Console.WriteLine("");
                Console.Write("Hi! " + studname + "you Passed");
                Console.WriteLine("");
                break;

            case 3:
                if (rate < 84 && rate > 80)

                    Console.Write("Rate = 1.00");
                Console.WriteLine("");
                Console.Write("Hi! " + studname + "you Passed");
                Console.WriteLine("");
                break;

            case 4:
                if (rate < 79 && rate > 75)

                    Console.Write("Rate = 1.00");
                Console.WriteLine("");
                Console.Write("Hi! " + studname + "you Passed");
                Console.WriteLine("");
                break;

            case 5:
                if (rate < 75)

                    Console.Write("Rate = 5.00");
                Console.WriteLine("");
                Console.Write("Hi! " + studname + "you Failed");
                Console.WriteLine("");
                break;


        }





        Console.ReadLine();
    }

Answer 1

你误解了switch - 块的作用。如果您正在测试的值仅采用几个设置值中的一个，则使用它。

尝试完全删除switch - 块并重新编写此代码以使用一系列if / else - 块。另请注意，您需要处理rate = 90等边缘情况;您还需要检查rate >= 90以捕获此案例：

if (rate < 100 && rate >= 90)
{
    Console.Write("Rate = 1.00");
    Console.WriteLine("");
    Console.Write("Hi! " + studname + "you Passed");
    Console.WriteLine("");
}
else if (rate < 89 && rate >= 85)
{
    Console.Write("Rate = 1.00");
    Console.WriteLine("");
    Console.Write("Hi! " + studname + "you Passed");
    Console.WriteLine("");
}
else ...

或者如果你真的想在每个案例中做同样的事情，除非rate < 75，你可以简化为：

if (rate >= 75)
{
    Console.Write("Rate = 1.00");
    Console.WriteLine("");
    Console.Write("Hi! " + studname + "you Passed");
    Console.WriteLine("");
}
else
{
     Console.Write("Rate = 5.00");
     Console.WriteLine("");
     Console.Write("Hi! " + studname + "you Failed");
     Console.WriteLine("");
}

甚至只是这样的事情：

Console.Write("Rate = {0}", (rate >= 75) ? "1.00" : "5.00");
Console.WriteLine("");
Console.Write("Hi! {0} you {1}", studname, (rate >= 75) ? "Passed" : "Failed");
Console.WriteLine("");

Answer 2

您的案例值不正确，switch语句正在启用案例值，因此在这种情况下，只有在rate == 1时才会调用案例1，依此类推，因此您需要按顺序修改这些值把它输出。

C＃开关盒没有出现

2 个答案: