sdk/samples/all in on code/Visual Studio 2008/CSEFEntityDataModel/TablePerHierarchy/TPHClass.cs

   1 /****************************** Module Header ******************************\
   2 * Module Name:    TPHClass.cs
   3 * Project:        CSEFEntityDataModel
   4 * Copyright (c) Microsoft Corporation.
   5 *
   6 * This example demonstrates how to establish table per hierarchy inheritance.
   7 * A table-per-type model is a way to model inheritance where each entity is
   8 * mapped to a distinct table in the store. Then it shows how to query a list
   9 * of people, get the corresponding properties of Person, Student and
  10 * BusinessStudent.
  11 *
  12 * This source is subject to the Microsoft Public License.
  13 * See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
  14 * All other rights reserved.
  15 *
  16 * THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
  17 * EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
  18 * WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
  19 \***************************************************************************/
  20
  21 #region Using directives
  22 using System;
  23 using System.Collections.Generic;
  24 using System.Linq;
  25 using System.Text;
  26 #endregion
  27
  28
  29 namespace CSEFEntityDataModel.TablePerHierarchy
  30 {
  31     public static class TPHClass
  32     {
  33         // Test the query method in TPHClass
  34         public static void TPHTest()
  35         {
  36             Query();
  37         }
  38
  39         // Query a list of people, print out the properties of Person,
  40         // Student and BusinessStudent
  41         public static void Query()
  42         {
  43             using (EFTPHEntities context = new EFTPHEntities())
  44             {
  45                 var people = from p in context.People
  46                              select p;
  47
  48                 foreach (var p in people)
  49                 {
  50                     Console.WriteLine("Student {0} {1}",
  51                         p.LastName,
  52                         p.FirstName);
  53
  54                     if (p is Student)
  55                     {
  56                         Console.WriteLine("EnrollmentDate: {0}",
  57                             ((Student)p).EnrollmentDate);
  58                     }
  59                     if (p is BusinessStudent)
  60                     {
  61                         Console.WriteLine("BusinessCredits: {0}",
  62                             ((BusinessStudent)p).BusinessCredits);
  63                     }
  64                 }
  65
  66             }
  67         }
  68     }
  69 }