如果我输入一个负数，但它不起作用，则控制台应该引发异常。我在这里想念什么吗？

Question

    public decimal CurrentBalance = 1000.00m;

    public decimal WithdrawCurrentAmount { get; set; }





    public decimal MakeWithdraw()
    {
        Console.WriteLine("How much would you like to withdraw from your Current account?", WithdrawCurrentAmount);

        if (WithdrawCurrentAmount < 0) 
        {
            throw new Exception("You cannot withdraw a negative amount" );               
        }

        WithdrawCurrentAmount = Convert.ToDecimal(Console.ReadLine());

        CurrentBalance = CurrentBalance - WithdrawCurrentAmount;
        Console.WriteLine("\nAvailable Current Balance is now: {0}", CurrentBalance);
        return CurrentBalance;     

Answer 1

您必须将Convert行移至if语句之前，否则用户输入的值不会设置到您的测试变量中

Answer 2

您应该在检查之前分配值：

WithdrawCurrentAmount = Convert.ToDecimal(Console.ReadLine()); // this line now is before checking 

if (WithdrawCurrentAmount < 0) 
{
   throw new Exception("You cannot withdraw a negative amount" );   
}

CurrentBalance = CurrentBalance - WithdrawCurrentAmount;
Console.WriteLine("\nAvailable Current Balance is now: {0}", CurrentBalance);

return CurrentBalance;