CODEWITHSUNDEEP
c#performanceoopvisual-c++interface
Robin Rodricks
Robin Rodricks

Reputation: 113976

Are virtual properties slower than concrete properties?

Say I have a C# interface called IMyInterface defined as follows:

// C# code
public interface IMyInterface
{
  string MyProperty { get; }
}

Assume I also have a C++/CLI class, MyConcreteClass, that implements this interface and whose header is declared as follows:

public ref class MyConcreteClass : public IMyInterface
{
 public:
  virtual property String^ MyProperty 
  {
    String^ get() sealed { return String::Empty; };
    void set( String^ s ) sealed { };
  }
};

Obviously when you access a virtual member through the interface, the runtime must look for an implementation in the class, and will be slower than if the member was not virtual.

IMyInterface obj;
obj->MyProperty = "HELLO";

I'm asking specifically about the performance of using virtual members directly on the concrete object type. Is this slower if MyProperty was a virtual member?

MyConcreteClass obj;
obj->MyProperty = "HELLO";

Upvotes: 1

Views: 795

Answers (1)

uriDium
uriDium

Reputation: 13420

Virtual methods are slower because the runtime has to check for an actual implementation of the method. So it is 1 additional check. You can still hundreds of thousands of these per second. So don't stress about it. In Java every method is virtual by default.

UPDATE: I am not sure about how introducing c++ changes things. My guess is that is would be similar because you are still accessing a virtual method. I am not sure how it would change it. But once again this is just my guess. Hopefully someone else can help out more.

Upvotes: 4

Related Questions