C# explicit interface implementation（顯式介面實現）

C# explicit interface implementation

某個類要實現兩個包含相同方法名的介面, 應該如何實現這兩個方法？

 1 namespace ExplicitInterfaceImplementation
 2 {
 3     class Program : IPrintOne,IPrintTwo, IPrintThree
 4     {
 5         static void Main(string[] args)
 6         {
 7             Program p = new Program();
 8             p.Print();
 9             (p as IPrintTwo).Print();
10             ((IPrintThree)p).Print();
11         }
12 
13 
14 
15         public void Print()
16         {
17             Console.WriteLine("Print One Interface");
18         }
19         // explicitly implement IPrintTwo
20         void IPrintTwo.Print()
21         {
22             Console.WriteLine("Print Two Interface");
23         }
24         // explicitly implement IPrintThree
25         string IPrintThree.Print()
26         {
27             Console.WriteLine("Print two Interface");
28             return "asd";
29         }
30     }
31 
32     interface IPrintOne
33     {
34         void Print();
35     }
36 
37     interface IPrintTwo
38     {
39         void Print();
40     }
41 
42     interface IPrintThree
43     {
44         string Print();
45     }
46 }

以上Demo中共有3個擁有相同方法名的interface，Program類繼承了這三個介面，使用explicit interface implementation實現IPrintTwo和IPrintThree介面的方法

顯示實現的介面方法前不能加access modifier，且調用該方法時需將Program類轉換位介面才能調用， 不能直接通過類引用調用。

When a class explicitly implements an interface member, the interface member can no longer be accessed thru class reference variable, but only thru the interface reference variable.

以上Demo的運行結果：

Print One Interface　　
Print Two Interface　　
Print Three Interface