inheritance and static

[Adam Klobukowski]

Consider following example:

class A
{
public static Method()
{
/* ... */
}
}

class B : A
{
}

How can i chcek in Method() if it was called as B.Method() or A.Method()?

 

[Guest]

Maybe like this:

class testA
{
public void Method()
{System.Windows.Forms.MessageBox.Show(this.ToString());}
}


class testB : testA
{
}

testA local_A = new testA();
local_A.Method();

testB local_B = new testB();
local_B.Method();

Frank Uray

 

[adamgilmore]

Hi Adam,

Looking at the generated IL (dissasembled using Reflector
http://www.aisto.com/roeder/dotnet/) it looks like the actual call is
to A.Method regardless of how you write the c#.

adam

 

[Nick Hounsome]

Consider following example:

class A
{
public static Method()
{
/* ... */
}
}

class B : A
{
}

How can i chcek in Method() if it was called as B.Method() or A.Method()?

class A {

public static void M() { M(false); }

protected static void M(bool derived){/* the biz */}}

class B : A{new static void M(){A.M(true);}}

 

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

Remember that the entire point of the question was the fact that Method was
static

 

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

Frankly I do not think you can tell, either B.Method or A.Method should
gets resolve at compile time to call the correct method.

Why you need to know that?

 

[Adam Klobukowski]

Ignacio Machin ( .NET/ C# MVP ) napisa³(a):

Hi,

Frankly I do not think you can tell, either B.Method or A.Method should
gets resolve at compile time to call the correct method.

Why you need to know that?

Well, the whole idea seems to be flawed end will be redone in some other
way. The point was to be able to have a static function in class that
could beahave in different manner, dependint on classes that inherit
from it.

 

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

Well, the whole idea seems to be flawed end will be redone in some other
way. The point was to be able to have a static function in class that
could beahave in different manner, dependint on classes that inherit from
it.

What you want is a virtual method.

Also take a look at the singleton pattern, maybe you want something like
that.

 

[Guest]

Well, the whole idea seems to be flawed end will be redone in some other

way. The point was to be able to have a static function in class that
could beahave in different manner, dependint on classes that inherit
from it.

Yeah, the base class knows nothing about derived classes. Derived classes
will need to implement their specific functionality. It's very difficult to
break polymorphism, but it's always fun to try.

 

[John Murray]

Not really an answer, but I had a similar question on an interview ...
and the solution I came up with was to throw an exception in the static
method and walk the stack trace to find the class making the call.

 

[Jon Skeet [C# MVP]]

Not really an answer, but I had a similar question on an interview ...
and the solution I came up with was to throw an exception in the static
method and walk the stack trace to find the class making the call.

That's not reliable - it could be misled by inlining, for instance.

The real solution is not to use a design which goes against the
language and platform idioms.