Convert.ToDouble 引发 FormatException

Question

如何跳过“System.FormatException”？

示例：

    public void HowMuchBookCar()
    {
        Console.Write("\nOk, how much Euros you want to book in 'CarAndBeauty':  ");
        double howMuch = Convert.ToDouble(Console.ReadLine());
        CarAndBeauty = Input(CarAndBeauty, howMuch);
        Save(@"C:\Users\tobia\Desktop\Neuer Ordner\JanuaryCategorie.txt");
        Console.Clear();
        WannaBook();
    }

此方法是在“汽车与美容”类别中预订特定金额。如果用户在这里键入例如“G”（或不适用于此变量的内容），它会抛出“System.FormatException”并且程序停止工作...

这很有道理……但是我怎样才能防止抛出异常而不是抛出特定代码呢？（例如：“请输入有效信息！”）

Answer 1

要避免 FormatException，请改用 double.TryParse。

您可以这样做：

double result;

while (true) // until user has typed something correct
{
    Console.WriteLine("Input a number:");

    var line = Console.ReadLine();

    // NOTE: optionally here, you may want to exit program if say, user has typed 'exit'

    if (double.TryParse(line, out result))
        break;

    Console.WriteLine("Input was not recognized");
}

Console.WriteLine($"You typed: {result:G}");

Convert.ToDouble 引发 FormatException

Convert.ToDouble raises a FormatException

c#

exception

formatexception