XAF : Implement One-to-Many Relationship

The following snippet of code present One-to-Many Relationship between Department and Contact business classes, in which Department object has many Contacts.
To implement the "One" part of the Department-Contacts relationship, decorate the Contact class Department property with the Association attribute.

   1:  <DefaultClassOptions()> _

   2:  Public Class Contact

   3:      Inherits Person

   4:      '...

   5:      Private fDepartment As Department

   6:      <Association("Department-Contacts", GetType(Department))> _

   7:      Public Property Department() As Department

   8:          Get

   9:              Return fDepartment

  10:          End Get

  11:          Set(ByVal value As Department)

  12:              SetPropertyValue("Department", fDepartment, value)

  13:          End Set

  14:      End Property

  15:      '...

  16:  End Class

  17:   

  18:   

To implement the "Many" part of the Department-Contacts relationship, add the Contacts property to the Department class and decorate this property with the Association attribute.

   1:  Public Class Department

   2:      Inherits BaseObject

   3:      '...

   4:      <Association("Department-Contacts", GetType(Contact))> _

   5:      Public ReadOnly Property Contacts() As XPCollection

   6:          Get

   7:              Return GetCollection("Contacts")

   8:          End Get

   9:      End Property

  10:  End Class

With the code above, necessary intermediate tables and relationships will be generated automatically.


[eXpressApp Framework]