ローンプログラムに問題があり、インタフェースがC＃

Question

インタフェースに問題があるようです。私はすべての計算がローンプログラムのために働く場所を持っていますが、私はどのように私のインターフェースを呼び出すのか分からないようです。私はそれがおそらく私が見落としているマイナーなものだと確信していますが、何らかの理由で私は空白を持っています。

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 
{ 

} 

Answer 1

これは役に立ちますか？ See it working here.

using System; 

public class Program 
{ 
    // Here we instantiate or construct a new instance of ThingWithMessage 
    // but we refer to it as thing of type IMyInterface, 
    // this works because ThingWithMessage implements IMyInterface. 
    // Then we use the interface implementation to get a message and 
    // write it to the console. 
    public static void Main() 
    { 
     IMyInterface thing = new ThingWithMessage(); 
     Console.WriteLine(thing.GetMessage()); 
    }  
} 

// This defines a type, or contract that classes can implement 
interface IMyInterface 
{ 
    string GetMessage(); 
} 

// This is a class that implements the IMyInterface interface 
// effectively, it makes a promise to keep the contract 
// specified by IMyInterface. 
class ThingWithMessage : IMyInterface 
{ 
    public string GetMessage() 
    { 
     return "yes, this works."; 
    } 
} 

Answer 2

これは、あなたが使用できる何かであるかもしれない：

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(); 
    } 
}