接口和类之间的区别是什么？为什么可以在类中直接实现方法，为什么要使用接口？

当您想创建类似的东西时，接口是非常好的：

using System;namespace MyInterfaceExample{    public interface IMyLogInterface    {        //I want to have a specific method that I'll use in MyLogClass        void WriteLog();}    public class MyClass : IMyLogInterface    {        public void WriteLog()        { Console.Write("MyClass was Logged");        }    }    public class MyOtherClass : IMyLogInterface    {        public void WriteLog()        { Console.Write("MyOtherClass was Logged"); Console.Write("And I Logged it different, than MyClass");        }    }    public class MyLogClass    {        //I created a WriteLog method where I can pass as a parameter any object that implements IMyLogInterface.        public static void WriteLog(IMyLogInterface myLogObject)        { myLogObject.WriteLog(); //So I can use WriteLog here.        }    }    public class MyMainClass    {        public void DoSomething()        { MyClass aClass = new MyClass(); MyOtherClass otherClass = new MyOtherClass(); MyLogClass.WriteLog(aClass);//MyClass can log, and have his own implementation MyLogClass.WriteLog(otherClass); //As MyOtherClass also have his own implementation on how to log.        }    }}

在我的示例中，我可以是一名编写人员的开发人员

MyLogClass

IMyLogInterface

WriteLog()

MyLogClass