若还不清楚NBear中如何实现ORM，请先阅读Teddy所写的《
NBearV3 Step by Step教程——ORM篇》。通常在一些应用中所使用到的字段不仅仅来左一个数据表，如一个文章列表GirdView中，使用到了Content、User、Category三个表中的项。
关系图如下：
Content.cs
1
public interface Content : Entity
2 
{
3
[PrimaryKey]
4 int ID
5
{
6 get;
7
}
8
9 [ManyToManyQuery(typeof(ContentTag), LazyLoad = true)]
10 Tag[] Tags
11 { get;set; }
12
13 [FkReverseQuery(LazyLoad = false)]
14 Category Category
15 {
16 get;
17 set;
18 }
19
20 DateTime? ModifiedDate
21 {
22 get;
23 set;
24 }
25
26 [FkReverseQuery(LazyLoad = false)]
27 [MappingName("UserID")]
28 User User
29 {
30 get;
31 set;
32 }
33
34 [SqlType("nvarchar(100)")]
35 string Title
36 {
37 get;
38 set;
39 }
40
41 [SqlType("ntext")]
42 string Body
43 {
44 get;
45 set;
46 }
47
48 [SqlType("ntext")]
49 string Summary { get;set;}
50
51 [SqlType("nvarchar(250)")]
52 string Link
53 {
54 get;
55 set;
56 }
57
58 int TopSort
59 {
60 get;
61 set;
62 }
63
64 bool Visible
65 {
66 get;
67 set;
68 }
69
70 int Hits
71 {
72 get;
73 set;
74 }
75
76 [SqlType("nvarchar(50)")]
77 string IP
78 {
79 get;
80 set;
81 }
82
83 bool AllowComment
84 {
85 get;
86 set;
87 }
88
89 int CommentCount
90 {
91 get;
92 set;
93 }
94
95 [FkQuery("Content", OrderBy = "{ID} DESC", Contained = true, LazyLoad = true)]
96 Comment[] Comments
97 {
98 get;
99 set;
100 }
101
}User.cs
1public interface User : Entity
2 {
3 [PrimaryKey]
4 int ID
5 {
6 get;
7 }
8
9 [SqlType("nvarchar(50)")]
10 string Name
11 {
12 get;
13 set;
14 }
15
16 [SqlType("nvarchar(50)")]
17 string Email
18 {
19 get;
20 set;
21 }
22
23 [FkQuery("UserID", Contained = true, LazyLoad = true)]
24 UserProfile Profile
25 {
26 get;
27 set;
28 }
29
30 [ManyToManyQuery(typeof(UserGroup), OrderBy = "{Name} DESC", LazyLoad = true)]
31 [SerializationIgnore]
32 Group[] Groups
33 {
34 get;
35 set;
36 }
37
38 [ManyToManyQuery(typeof(UserRole), OrderBy = "{Name} DESC", LazyLoad = true)]
39 [SerializationIgnore]
40 Role[] Roles
41 {
42 get;
43 set;
44 }
45
46 [FkQuery("UserID", OrderBy = "{Name} DESC", Contained = true, LazyLoad = true)]
47 [SerializationIgnore]
48 Tag[] Tags
49 {
50 get;
51 set;
52 }
53
54 [FkQuery("User", OrderBy = "{ID} DESC", Contained = true, LazyLoad = true)]
55 [SerializationIgnore]
56 Content[] Contents
57 {
58 get;
59 set;
60 }
61
62 [FkQuery("User", OrderBy = "{ID} DESC", Contained = true, LazyLoad = true)]
63 [SerializationIgnore]
64 Comment[] Comments
65 {
66 get;
67 set;
68 }
69
70 [FkQuery("User", OrderBy = "{Name} DESC", Contained = true, LazyLoad = true)]
71 [SerializationIgnore]
72 Category[] Categories
73 {
74 get;
75 set;
76 }
77
78 UserStatus Status
79 {
80 get;
81 set;
82 }
83
84 [SqlType("nvarchar(50)")]
85 string LogOnName
86 {
87 get;
88 set;
89 }
90
91 [SqlType("nvarchar(50)")]
92 string Password
93 {
94 get;
95 set;
96 }
97
98 [SqlType("nvarchar(100)")]
99 string PassQuestion
100 {
101 get;
102 set;
103 }
104
105 [SqlType("nvarchar(100)")]
106 string PassAnswer
107 {
108 get;
109 set;
110 }
111
112 [FkQuery("UserID", Contained = true, LazyLoad = true)]
113 UserPhone[] Phones
114 {
115 get;
116 set;
117 }
118
119 [SqlType("nvarchar(30)")]
120 string No
121 {
122 get;
123 set;
124 }
125
126 [SqlType("nvarchar(4)")]
127 string Sex
128 {
129 get;
130 set;
131 }
132
133 DateTime? Birthday
134 {
135 get;
136 set;
137 }
138
139 DateTime? CreateDate
140 {
141 get;
142 set;
143 }
144
145 DateTime? LogOnDate
146 {
147 get;
148 set;
149 }
150
151 int LogOnCount
152 {
153 get;
154 set;
155 }
156 }
Category.cs
1public interface Category : Entity
2 {
3 [PrimaryKey]
4 int ID
5 {
6 get;
7 }
8
9 [SqlType("nvarchar(50)")]
10 string Name
11