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{ get; set; } #endregion #region Navigation Properties public virtual Reservation Reservation { get { return _reservation; } set { if (!ReferenceEquals(_reservation, value)) { var previousValue = _reservation; _reservation = value; FixupReservation(previousValue); } } } private Reservation _reservation; #endregion #region Association Fixup private void FixupReservation(Reservation previousValue) { if (previousValue != null && previousValue.Payments.Contains(this)) { previousValue.Payments.Remove(this); } if (Reservation != null) { if (!Reservation.Payments.Contains(this)) { Reservation.Payments.Add(this); } if (ReservationID != Reservation.ReservationID) { ReservationID = Reservation.ReservationID; } } } #endregion } } Taking a quick peek into the generated Customer class, you’ll find that the template also read the default value setting for CustomerID and applied it: private int _customerTypeID = 1;
Modifying the POCO Template Although this template is Microsoft’s default for creating a POCO class it doesn’t mean it’s perfectly suited to your domain. Following are two examples of modifying this template. The first targets scenarios where you do not want the dynamic proxies. In that case, you can modify the template to remove its insertion of virtual in front of properties. If you do a quick search on the word virtual you can find the method that inserts that keyword. The method appends virtual to only nonprivate properties. string PropertyVirtualModifier(string accessibility) { return accessibility + (accessibility != "private" ? " virtual" : ""); } These are called when the properties are being created. Here is the VirtualModifier being used as each primitive type is being declared: The method is responsible for applying the accessibility (e.g., public or private) as well as the virtual keyword. Remove the PropertyVirtualModifier function that surrounds the Accessibility.ForProperty method to insert only the accessibility and not the virtual keyword: In Chapter 11, we modified the Activity class so that it will validate the length of the ActvityName field. We did this by manually adding code, along with the desired maximum length, in a partial class. What’s frustrating is that the maximum length is defined in the database and available in the SSDL, and in most cases (except when running the Update Model Wizard), the property was brought forward to the conceptual model as well. But Entity Framework doesn’t automatically validate against that property. You can modify the template to read the Max Length attribute of String properties and build validation code when the code is generated. You can accomplish this with the addition of some new processor methods and then calling those in during the code generation. You can find the section of the template that contains the processing method near the bottom of the template file. It is introduced by a set of comments surrounded by tags. This is followed by the namespace, some using (or Include) statements, 11 lines of code, and then finally the first processing method, WriteFooter. I prefer to insert my custom processing methods before this first method so that I can easily find them. The two methods to include are the ones that get an attribute value given the name of the attribute. For example, if you pass in Max Length it will read the metadata for that property and return the value, say, 50, of the Max Length property.
Page 1 and 2: Free Sampler
Page 3 and 4: Programming Entity Framework by Jul
Page 5 and 6: The EDM Within the Entity Framework
Page 7 and 8: Retrieving a Single Entity with Get
Page 9 and 10: Breaking Apart the ObjectQuery 222
Page 11 and 12: Using a New EntityDataSource to Add
Page 13 and 14: Insert, Update, and Delete Function
Page 15 and 16: Digging Through ObjectStateEntry 53
Page 17 and 18: 19. Using Your Own Custom Classes .
Page 19 and 20: Designing the Service Interface 725
Page 21 and 22: In addition to POCO support, the te
Page 23 and 24: using System.Text; namespace Chapte
Page 25 and 26: } } public ObjectSet Addresses { ge
Page 27 and 28: } If you run the code now, you will
Page 29 and 30: Using Proxies to Enable Change Noti
Page 31 and 32: Figure 13-2. A high-level view of t
Page 33 and 34: Rule 2: To enable lazy loading on a
Page 35: using System.Collections.ObjectMode
Page 39 and 40: The next step is to modify the temp
Page 41 and 42: get; set; } public string Street1 {
Page 43: Want to read more? You can find thi

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