Making dervied class from base class

[Thomas C]

I'm looking for the best way to solve the following problem:

public class Foo
{
public void Bar() {}
}

public class Alice : Foo
{
public void Zed() {}
}

Foo foo = new Foo();
What I want to do is to make a new instance of Alice using the data from my
instance of foo like so:

Alice alice = (Alice)foo;
or
Alice alice = new Alice(foo);

Right now, the best solution I have found is to implement a Copy method on
the base class which takes a base class instance and overwrites the local
instance's data with the passed instance's data (e.g. public void Copy(Foo
foo)).

Any better suggestions?

Tom

[Marina]

If you have an instance of Foo, there is nothing you can do to promote it to
Alice. It's a Foo, not an Alice!

Now, if you had an instance of Alice, you could treat it as a Foo, since an
Alice is a Foo by definition. But not necessarily the other way around.

Now, if you add a constructor to Alice that takes a Foo, and then it copies
all pertinent information from Foo, then that will work. But you are pretty
much restricted to this type of copy, like in your method.

"Thomas C" <th****@newsgroup.nospam> wrote in message
news:%2*****************@TK2MSFTNGP12.phx.gbl...

I'm looking for the best way to solve the following problem:

public class Foo
{
public void Bar() {}
}

public class Alice : Foo
{
public void Zed() {}
}

Foo foo = new Foo();
What I want to do is to make a new instance of Alice using the data from my instance of foo like so:

Alice alice = (Alice)foo;
or
Alice alice = new Alice(foo);

Right now, the best solution I have found is to implement a Copy method on
the base class which takes a base class instance and overwrites the local
instance's data with the passed instance's data (e.g. public void Copy(Foo
foo)).

Any better suggestions?

Tom