C# Hiding, overriding and calling function from base class.
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by Lukasz Lysik
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Published on 2010-03-23T12:36:39Z
Indexed on
2010/03/23
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I'm learning C# and I encountered the following problem. I have two classes: base and derived:
class MyBase
{
public void MyMethod()
{
Console.WriteLine("MyBase::MyMethod()");
}
}
class MyDerived: MyBase
{
public void MyMethod()
{
Console.WriteLine("MyDerived::MyMethod()");
}
}
For now, without virtual
and override
key words. When I compile this I get the warning (which is of course expected) that I try to hide MyMethod
from MyBase
class.
What I want to do is to call the method from the base class having an instance of derived class. I do this like this:
MyDerived myDerived = new MyDerived();
((MyBase)myDerived).MyMethod();
It works fine when I do not specify any virtual
, etc. keywords in the methods. I tried to put combination of the keywords and I got the following results:
| MyBase::MyMethod | MyDerived::MyMethod | Result printed on the console |
| -----------------|---------------------|-------------------------------|
| - | - | MyBase::MyMethod() |
| - | new | MyBase::MyMethod() |
| virtual | new | MyBase::MyMethod() |
| virtual | override | MyDerived::MyMethod() |
I hope the table is clear to you. I have two questions:
- Is it the correct way to call the function from the base class (
((MyBase)myDerived).MyMethod();
)? I know aboutbase
keyword, but it can be called only from the inside of the derived class. Is it right? - Why in the last case (with
virtual
andoverride
modifiers) the method which was called came from the derived class? Would you please explain that?
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