c# - 使用int32.TryParse处理错误

Question

我在添加错误消息和对此进行重新循环时遇到麻烦，想知道如何添加“错误的输入，然后重试”，然后尝试写下正确的数字。它不会崩溃，到目前为止还不错，但是我想在不使用try and catch和一个循环的情况下出错，该循环迫使您只写正确的数字。

这是我到目前为止完成的代码:

bool loopie = true;
int result;
int result2;
int result3;

while (loopie)
{

    Console.Write("Number one: ");             
    Int32.TryParse(Console.ReadLine(), out result);

    Console.WriteLine(" ");
    Console.Write("Number two: ");
    Int32.TryParse(Console.ReadLine(), out result2);

    Console.WriteLine(" ");
    Console.Write("Number two: ");
    Int32.TryParse(Console.ReadLine(), out result3);

    Console.WriteLine(" ");
    int summa = result + result2 + result3;
    Console.WriteLine("summan: " + summa);

}
Console.ReadKey();

Answer 1

TryParse返回 bool(boolean) 值，该 bool(boolean) 值指定转换是否正确完成。所以用吧

while (loopie)
{
    Console.Write("Number one: ");
    if (!Int32.TryParse(Console.ReadLine(), out result))
    {
        Console.WriteLine("Wrong input. try again.");
        continue;
    }

    Console.WriteLine(" ");
    Console.Write("Number two: ");
    if (!Int32.TryParse(Console.ReadLine(), out result2))
    {
        Console.WriteLine("Wrong input. try again.");
        continue;
    }

    Console.WriteLine(" ");
    Console.Write("Number two: ");
    if (!Int32.TryParse(Console.ReadLine(), out result3))
    {
        Console.WriteLine("Wrong input. try again.");
        continue;
    }

    Console.WriteLine(" ");
    int summa = result + result2 + result3;
    Console.WriteLine("summan: " + summa);
}

或者，如果您不想在失败后重设整个过程，请使用其他时间。

do  
{
    Console.Write("Number one: ");
    Console.WriteLine("Wrong input. try again.");
} while (!Int32.TryParse(Console.ReadLine(), out result)); // write this for all 3 inputs.