C# 贷款程序与接口c的故障#

我似乎在界面方面遇到了问题。我有它，我所有的计算工作为贷款计划，但我似乎不知道如何调用我的接口。我肯定这可能是我忽略了一些次要的东西，但出于某种原因，我有一个空白

Interface:
interface IMyInterface
{
    string iMessage();
}


 public class C1
{
    static void Main(string[] args)
    {
        double interests = 0.0;
        double years = 0.0;
        double loan_amount = 0.0;
        double interest_rate = 0.0;


        Console.Write("Enter Loan Amount:$ ");
        loan_amount = Convert.ToDouble(Console.ReadLine());
        Console.Write("Enter Number of Years: ");
        years = Convert.ToDouble(Console.ReadLine());
        Console.Write("Enter Interest Rate: ");
        interest_rate = Convert.ToDouble(Console.ReadLine());
        interests = loan_amount * interest_rate * years;
        Console.WriteLine("\nThe total interests is {0}", interests);
        Console.ReadLine();




    }

    public string iMessage()
    {
        return Console.WriteLine("Be Ready!");  
    }
}

class Program
{

}

这有用吗

---

这可能是您可以使用的：

interface IMyInterface
{
    double Calculate();
}

class MyCalculationLogics : IMyInterface
{
    public double Calculate(double loan_amount, double years, double interest_rate)
    {
        return loan_amount * interest_rate * years;
    }
}

public class Program
{
    static void Main(string[] args)
    {
        ....
        // Get the values from the user
        ....

        IMyInterface myCalc = new MyCalculationLogics();
        interests = myCalc.Calculate(loan_amount, years, interest_rate);

        Console.WriteLine("\nThe total interests is {0}", interests);
        Console.ReadLine();
    }
}

---

你的类目前没有声明它实现了接口，你也从来没有创建过你的类的实例，或者引用过接口。另外，

Console.WriteLine

是一个无效的方法，所以你不能在像这样的返回语句中使用它……Shade，换句话说，不管Jon Skeet说什么，都把它当作法律。或者，你可以在发布之前试着调试你的代码，永远不必浪费Jon Skeet的时间。@JonSkeet好的，谢谢你指出这一点。我很感激。当你说界面时，你是指控制台应用程序中的用户界面吗？哪个请求输入并给出输出？=！是的，这个修好了。谢谢你花时间来帮助我。@Shade，嘿，我几乎还记得刚开始时的感觉。谢谢你也解释清楚了。你的解释使它更容易理解。

interface IMyInterface
{
    double Calculate();
}

class MyCalculationLogics : IMyInterface
{
    public double Calculate(double loan_amount, double years, double interest_rate)
    {
        return loan_amount * interest_rate * years;
    }
}

public class Program
{
    static void Main(string[] args)
    {
        ....
        // Get the values from the user
        ....

        IMyInterface myCalc = new MyCalculationLogics();
        interests = myCalc.Calculate(loan_amount, years, interest_rate);

        Console.WriteLine("\nThe total interests is {0}", interests);
        Console.ReadLine();
    }
}