C# Online Compiler | .NET Fiddle

<no name> by Anonymous

using System;
					
public class Program
{
	public static void Main()
	{

	}
}

public class ClassA
{
}

public class ClassB : ClassA
{
}

public class ServiceA
{
	public virtual ClassA GetClass() => new ClassA();	
}

public class ServiceB
{
	public override ClassB GetClass() => new ClassB();	
}

public interface IInterfaceA
{
	public ClassA CreateClass()		
}

public class ImplementaceInterfaceA : IInterfaceA
{
	public ClassB CreateClass()
	{
		return null;
	}
}

​x
 
using System;
                    
public class Program
{
    public static void Main()
    {
​
    }
}
​
public class ClassA
{
}
​
public class ClassB : ClassA
{
}
​
public class ServiceA
{
    public virtual ClassA GetClass() => new ClassA();   
}
​
public class ServiceB
{
    public override ClassB GetClass() => new ClassB();  
}
​
public interface IInterfaceA
{
    public ClassA CreateClass()     
}
​
public class ImplementaceInterfaceA : IInterfaceA
{
    public ClassB CreateClass()
    {
        return null;
    }
}

Compilation error (line 31, col 29): ; expected
Compilation error (line 26, col 25): 'ServiceB.GetClass()': no suitable method found to override
Compilation error (line 34, col 39): 'ImplementaceInterfaceA' does not implement interface member 'IInterfaceA.CreateClass()'. 'ImplementaceInterfaceA.CreateClass()' cannot implement 'IInterfaceA.CreateClass()' because it does not have the matching return type of 'ClassA'.

Last Run:	9:19:38 am
Compile:	0.004s
Execute:	0s
Memory:	0b
CPU:	0s

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