Implementing a Property

The same as methods, properties (“get”, “let”, and “set”) from an interface could be implemented by another class. In Visual Basic 6, just as a method, it has to add the keyword Implements and declare the corresponding property with the name <Interface>_<PropertyName> in the class.

A difference between methods and properties is that the later could have just the “get”, “let” or “set” properties or a combination of them. In the implementing class the same kinds of properties must be implemented, which means that if in the interface the property implements the “get” and “let”, in the implementing class both properties must be applied as well.

The upgrading process is very similar to the methods conversion procedure. An interface must be generated, along with the CoClass class with the exposed methods. Moreover, for Visual Basic .NET the property must keep the same name, and the Implements keyword is added to the end with the corresponding property to be implemented.

For C# the changes imply renaming the property from <Interface>_<Property> to <Property>, and the Implements keyword is not needed.

Remember, just as with methods, the signature must be the same as the one from the interface.

Original VB6 code


AnInterface.cls

Property Get PhaseName() As String
    ' Code
End Property

Property Let PhaseName(ByVal v As String)
    ' Code
End Property

AClass.cls

Implements AnInterface
Property Get AnInterface_PhaseName() As String
    ' Code
End Property

Property Let AnInterface_PhaseName(ByVal v As String)
    ' Code
End Property

VBUC resulting VB.NET code


AnInterface.cls

Interface AnInterface
    Property PhaseName As String
End Interface
Friend Class AnInterface_CoClass
    Implements AnInterface
Public Property PhaseName() As String Implements AnInterface.PhaseName
        Get
            ' Code
        End Get
        Set(ByVal Value As String)
            ' Code
        End Set
End Property
End Class

AClass.cls

Friend Class AClass
    Implements AnInterface
    Property AnInterface_PhaseName() As String Implements AnInterface.PhaseName
        Get
            ' Code
        End Get
        Set(ByVal Value As String)
            ' Code
        End Set
    End Property
End Class

VBUC resulting C#.NET code

AnInterface.cls
    interface AnInterface
    {
        string PhaseName{ get; set; }
    } 
    internal class AnInterface_CoClass
    : AnInterface
    {
        public string PhaseName
        {
            get
            {
                // Code
                return String.Empty;
            }
            set
            {
                // Code
            }
        }
    }
AClass.cls
    internal class AClass
    : AnInterface
    {
            public string PhaseName
            {
                get
                {
                    // Code
                    return String.Empty;
                }
                set
                {
                    // Code
                }
        }
}