Question

int a = 0;
int b = 0;

for (int c = 0; c < 2; c++)
{
    Console.WriteLine("Give me a number");

    int h = Convert.ToInt16(Console.ReadLine());
    switch (c)
    {
        case 0:
            a = h;
            while (a <100 || a>250)
            {
                Console.WriteLine("That number is too large");
                break;
            }

            break;

        case 1:
            b = h;
            while (a < 100 || a > 250)
            {
                Console.WriteLine("That number is too large");
                break;
            }

            break;
    }
}

Console.WriteLine("{0}",a+b);
Console.ReadKey();

当我输入大于250或小于100的数字时，它会给我一条消息（“那个数字太大”），但问题是它仍然在代码末尾执行添加。我试图做到这一点，如果这些数字超出该范围，它再次问我数字。关于如何做到这一点的任何提示？

Answer 1

子程序是很棒的东西，在很多情况下很有用。

int GetNumberBetween( int minValue, int maxValue )
{
    int h;
    for (;;)
    {
        Console.WriteLine("Give me a number");
        h = Convert.ToInt32(Console.ReadLine());
        if ( h >= minValue && h <= maxValue )
            break;
        Console.WriteLine("I don't like that number, try again");
    }
    return( h );
}

void DisplaySum( void )
{
    int a = GetNumberBetween( 100, 250 );
    int b = GetNumberBetween( 100, 250 );
    Console.WriteLine("{0}",a+b);
    Console.ReadKey();
}

Answer 2

您需要更好地控制外部循环。而不是使用一段时间，只有当你有一个好的数字时才增加变量C.

int a = 0;
int b = 0;
int c = 0;
while (c < 2)
{
    Console.WriteLine("Give me a number");
    int h;
    if(!Int32.TryParse(Console.ReadLine(), out h)
    {
        Console.WriteLine("Not a valid number");
        continue;
    }
    switch (c)
    {
        case 0:
            a = h;
            if(a <100 || a>250)
                Console.WriteLine("That number is too large");
            else 
               c = 1;
            break;

        case 1:
            b = h;
            if(b < 100 || b > 250)
                 Console.WriteLine("That number is too large");
            else
               c = 2;
            break;
    }
}

Console.WriteLine("{0}",a+b);
Console.ReadKey();

顺便说一句，我建议使用Int32.TryParse而不是Convert.ToInt32（如果用户键入了无法转换为数字的内容，代码中会发生什么？）

我还在你的第二次测试中修正了一个拼写错误。您应该使用变量b而不是

Answer 3

你在想解决方案。如果你只是试图将两个数字相加，那么就这样做吧。从逻辑上考虑它。您可以根据需要添加错误消息。

获取
获取b
数字总和

注意：如果您需要汇总两个以上的数字，那么此解决方案将无效

//...
int a = 0;

//Capture a value for a, and range check it
while (a < 10 || a > 50)
{
    Console.WriteLine("Give me a number for (a)");
    a = Convert.ToInt32(Console.ReadLine());
}

int b = 0;

//Capture a value for b, and range check it
while (b < 10 || b > 50)
{
    Console.WriteLine("Give me a number for (b)");
    b = Convert.ToInt32(Console.ReadLine());
}

Console.WriteLine("{0}", a + b);
Console.ReadKey();
//...

编辑：

int a = 0;

//Get a value for a
while (true)
{
    Console.WriteLine("Give me a number for (a)");
    a = Convert.ToInt32(Console.ReadLine());

    //Range check and exit if valid
    if (a >= 10 && a <= 50)
        break;

    Console.WriteLine("That number is too large");
}

int b = 0;

//Get a value for b
while (true)
{
    Console.WriteLine("Give me a number for (b)");
    b = Convert.ToInt32(Console.ReadLine());

    //Range check and exit if valid
    if (b >= 10 && b <= 50)
        break;

    Console.WriteLine("That number is too large");
}

Console.WriteLine("{0}", a + b);
Console.ReadKey();

如何让这段代码正确循环？

3 个答案: