我想使用接口方法调用所有函数,但我不想创建实现接口的类的实例。我做了一些项目,我做了ISomeInterface proxy = ChannelFactory<SomeImplementation>().CreateChannel()
然后使用了proxy.Method()
等接口方法。我想做那样的事情,如果可能的话可能没有ChannleFactory
,我想知道是否有可能。
private static IUserInterface proxy;
[STAThread]
static void Main(string[] args)
{
bool closeApp = false;
do
{
proxy.PrintMenu();
int command;
Int32.TryParse(Console.ReadKey().KeyChar.ToString(), out command);
Console.WriteLine();
closeApp = proxy.SendMenuCommand(command);
} while (!closeApp);
// Aplikacija ugasena
Console.WriteLine("Application closed successfully. Press any key...");
Console.ReadKey();
}
弹出的错误是代理未设置为对象的实例。
接口只是一个契约,它与实例无关。如果一个类实现了接口,你可以将一个实例类型化为该接口并调用接口中定义的方法/属性..(它甚至不是代理)
该接口不包含任何实现。这只是一组必须实施的协议才能坚持合同。
所以你必须有一个实例。
在你的例子中:proxy.PrintMenu();
谁实施了PrintMenu()
?
我可能是这样的:
界面:
// This is the contract. (as you can see, no implementation)
public interface IUserInterface
{
void PrintMenu();
bool SendMenuCommand(int command);
}
首次实施:
// The class implements that interface, which it MUST implements the methods.
// defined in the interface. (except abstract classes)
public class MyUserInterface : IUserInterface
{
public void PrintMenu()
{
Console.WriteLine("1 - Option one");
Console.WriteLine("2 - Option two");
Console.WriteLine("3 - Option three");
}
public bool SendMenuCommand(int command)
{
// do something.
return false;
}
}
其他实施:
// same for this class.
public class MyOtherUserInterface : IUserInterface
{
public void PrintMenu()
{
Console.WriteLine("1) Submenu 1");
Console.WriteLine("2) Submenu 2");
Console.WriteLine("3) Submenu 3");
}
public bool SendMenuCommand(int command)
{
// do something.
return true;
}
}
你的主要:
private static IUserInterface menu;
[STAThread]
static void Main(string[] args)
{
bool closeApp = false;
// because the both classes implements the IUserInterface interface,
// the both can be typecast to IUserInterface
IUserInterface menu = new MyUserInterface();
// OR
//IUserInterface menu = new MyOtherUserInterface();
do
{
proxy.PrintMenu();
int command;
Int32.TryParse(Console.ReadKey().KeyChar.ToString(), out command);
Console.WriteLine();
closeApp = proxy.SendMenuCommand(command);
} while (!closeApp);
// Aplikacija ugasena
Console.WriteLine("Application closed successfully. Press any key...");
Console.ReadKey();
}