Implementing a derived association in ECO4
Eco4 introduces automatic subscriptions, so when implementing code derived attributes or associations, there is no need to handle the subscriptions manually any more. Once you have marked the attribute or association as derived in the model and updated your generated code, you should implement a method called "MyAttributeDerive" or "MyAssociationEndDerive". Suppose you have a model with two classes, Person and Project, and a derived association BigProjects between them like this:
The code to derive the BigProjects association end would look like this (add this method to the Person class):
private object BigProjectsDerive()
{
IList<Project> res = new List<Project>();
foreach (Project p in Projects)
if (p.Budget > 10000)
res.Add(p);
return res;
}