C#

public inteface MyInterface{
void IntefaceMethod();
}
public class ClassOne : myInterface
{
 public void IntefaceMethod(){
 } 
 ///a method that defined only in this class
 public void ClassOneMethod(){
 }
}
public class ClassTwo : myInterface
{
 public void IntefaceMethod(){
 } 
 ///a method that defined only in this class
 public void ClassTwoMethod(){
 }
}

MyInterface one = new ClassOne();
MyInterface two = new ClassTwo();

one.IntefaceMethod();
two.IntefaceMethod();

((ClassOne)one).ClassOneMethod();
((ClassTwo)two).ClassTwoMethod();

/*
this will throw exception
((ClassTwo)one).ClassOneMethod();
((ClassOne)two).ClassTwoMethod();
*/

mdkarimulla wrote:

Now my problem is do i need to have to separate interfaces, one for each class.

abstract class SomeClass {

abstract public void CommonMethod();
public void Class1_Method(){
// implementation here
}

public void Class2_Method(){
// implementation here
}
}

mdkarimulla wrote:

I need to write the implementation of this methods in classone also like

class MyApp {
    private static SafeHandle handle = new MyAppSafeHandle();
    public static KeepAlive() { GC.KeepAlive(handle); }
}
class MyLibSafeHandle : SafeHandle {
    public MyLibSafeHandle()
        : base(IntPtr.Zero, true)
    { MyApp.KeepAlive(); }

    protected override ReleaseHandle() {
        externRelease(handle);
        MyApp.KeepAlive();
    }
}

string URL = fetchinfo.ResponseUri.ToString();

System.IO.File.Copy("Source", "Destination");