Access the base class method with derived class objects

public class BaseClass
{
    public void Method1()
    {
        string a = "Base method";
    }
}

public class DerivedClass : BaseClass
{
    public new void Method1()
    {
        string a = "Derived Method";
    }
}

public class TestApp
{
    public static void main()
    {
        DerivedClass derivedObj = new DerivedClass();
        BaseClass obj2 = (BaseClass)derivedObj;
        obj2.Method1();  // invokes Baseclass method
    }
}