Implementing a Version check between an Abstract class and it's implementation
- by Michael Stum
I have this abstract class and concrete implementation (they are in different assemblies):
public abstract class MyAbstractClass
{
private static readonly int MyAbstractClassVersion = 1;
public abstract int ImplementedVersion { get; }
protected MyAbstractClass()
{
CheckVersion();
}
private void CheckVersion()
{
var message =
string.Format(
"MyAbstractClass implements Version {0}, concrete is Version {1}",
RepositoryVersion, ImplementedVersion);
if (!MyAbstractClassVersion.Equals(ImplementedVersion))
throw new InvalidOperationException(message);
}
}
public class ConcreteClass : MyAbstractClass
{
public ConcreteClass() : base() {
// ConcreteClass is guaranteed to have
// a constructor that calls the base constructor
// I just simplified the example
}
public override int ImplementedVersion
{
get { return 2; }
}
}
As you see, I call CheckVersion() from the abstract constructor, to get rid of the "virtual member call in base constructor" message, but I am not sure if that's really the way to do it. Sure, it works, but that doesn't mean it will always work, will it?
Also, I wonder if I can get the name of the Concrete Type from the CheckVersion() function?
I know that adding new abstract members will force an error anyway (System.TypeLoadException) and I'm not sure if I want this type of strict Versioning, but I'm just curious how it would be done properly given only the abstract class and an implementation (I know I could do it by using interfaces and/or a Factory pattern).
