覆盖财产

Question

I'm trying to override a property in my program. Here is basically what I'm trying to do :

class A { public int test = 7; }

class B : A { public int test = 8; }


class Program
{
    static void Main(string[] args)
    {
        A test1 = new A();
        A test2 = new B();

       Console.WriteLine(test1.test);
       Console.WriteLine(test2.test);

    }
}

This displays 7 in both case when I'd like it to display 8 in the 2nd case....

I've tried virtual and override as well as new (public new int test = 8;) But it doesn't seem to work

And yes I know I should use private and getters. I just want to know if it's possible ?

Edit : I'm not a native C# programmer so forgive me if i mix the terms (such as field and propertys)!

Answer 1

I'm trying to override a property in my program.

class A { public int test = 7; }

The problem is that int test is not a property , it is a public field . Fields cannot be overriden.

Here is an example of overriding a property:

class A {
    public virtual int test {
        get {return 7;}
    }
}

class B : A {
    public override int test {
        get {return 8;}
    }
}

Here is a demo of this code on ideone .

Answer 2

test is a field, not a property. You must change it to a property and add the virtual modifier to allow it to be overriden in a subclass. You must then use the override keyword to override the value returned in class B :

class A
{
    public virtual int test
    {
        get { return 7; }
    }
}

class B : A 
{
    public override int test
    {
        get { return 8; }
    }
}

Answer 3

Change this

A test2 = new B();

with this

B test2 = new B();

If you create test2 as A you call A methods