Strange error with constructors

[Fernando Rodríguez]

Hi,

If I try to compile the code below, I get a weird error that seems to be
related with hte constructors.

-------------------------------------
class Action : System.Object
{
Object _something;

public Action( Object something )
{
_something = something;
}

public virtual void go()
{
Console.WriteLine(_something.ToString());
}
}
class Prueba : Action
{
public override void go()
{
Console.Write("Prueba says: ");
base.go();
}
}

--------------------------------------------

The error says something like: no overload for the method Action requires 0
arguments.

What the Hell does this mean? O:-)

Thanks

[Patrik Löwendahl [C# MVP]]

When inheriting a base class you effectivly will cause the CLR to create an
instance of that base class.

Since your base class only have one constructor, and that constructor needs
a parameter. The CLR cannot create the base object.

To make this work, you need to supply the parameter to the base class from
the sub class.

Btw, what does Prueba mean ;)

<code>
class Prueba : Action
{
public Prueba() : base(null)
{}

public override void go()
{
Console.Write("Prueba says: ");
base.go();
}
}
</code>

--
Patrik Löwendahl [C# MVP]
www.cshrp.net - "Elegant code by witty programmers"

"Fernando Rodríguez" <fe*******************@fernando-rodriguez.com> wrote in
message news:73********************************@4ax.com...

Hi,

If I try to compile the code below, I get a weird error that seems to be
related with hte constructors.

-------------------------------------
class Action : System.Object
{
Object _something;

public Action( Object something )
{
_something = something;
}

public virtual void go()
{
Console.WriteLine(_something.ToString());
}
}
class Prueba : Action
{
public override void go()
{
Console.Write("Prueba says: ");
base.go();
}
}

--------------------------------------------

The error says something like: no overload for the method Action requires
0
arguments.

What the Hell does this mean? O:-)

Thanks

[Fernando Rodríguez]

On Sun, 10 Oct 2004 19:02:18 +0200, "Patrik Löwendahl [C# MVP]"
<pa**************@csharpsweden.com> wrote:

When inheriting a base class you effectivly will cause the CLR to create an
instance of that base class.

Since your base class only have one constructor, and that constructor needs
a parameter. The CLR cannot create the base object.

To make this work, you need to supply the parameter to the base class from
the sub class.
OK, I got it now. :-)
Btw, what does Prueba mean ;)

Test. :-)

[Jon Skeet [C# MVP]]

Fernando Rodríguez <fe*******************@fernando-rodriguez.com>
wrote:

If I try to compile the code below, I get a weird error that seems to be
related with hte constructors.

See http://www.pobox.com/~skeet/csharp/constructors.html

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[JuLiE Dxer]

I think that's Spanish for 'test'

On Sun, 10 Oct 2004 19:02:18 +0200, "Patrik Löwendahl [C# MVP]"
<pa**************@csharpsweden.com> wrote:

When inheriting a base class you effectivly will cause the CLR to create an
instance of that base class.

Since your base class only have one constructor, and that constructor needs
a parameter. The CLR cannot create the base object.

To make this work, you need to supply the parameter to the base class from
the sub class.

Btw, what does Prueba mean ;)

<code>
class Prueba : Action
{
public Prueba() : base(null)
{}

public override void go()
{
Console.Write("Prueba says: ");
base.go();
}
}
</code>