Generic method multiple (OR) type constraint

Question

Reading this, I learned it was possible to allow a method to accept parameters of multiple types by making it a generic method. In the example, the following code is used wi

Answer 1

If ChildClass means it is derived from ParentClass, you may just write the following to accept both ParentClass and ChildClass;

public void test(string a, T arg) where T: ParentClass 
{
    //do something
}

On the otherhand, if you want to use two different types with no inheritance relation between them, you should consider the types implementing the same interface;

public interface ICommonInterface
{
    string SomeCommonProperty { get; set; }
}

public class AA : ICommonInterface
{
    public string SomeCommonProperty
    {
        get;set;
    }
}

public class BB : ICommonInterface
{
    public string SomeCommonProperty
    {
        get;
        set;
    }
}

then you can write your generic function as;

public void Test(string a, T arg) where T : ICommonInterface
{
    //do something
}