mcs/class/System.ComponentModel.DataAnnotations/System.ComponentModel.DataAnnotations/AssociationAttribute.cs

   1 //
   2 // AssociationAttribute.cs
   3 //
   4 // Authors:
   5 //      Marek Habersack <mhabersack@novell.com>
   6 //
   7 // Copyright (C) 2010 Novell Inc. (http://novell.com)
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30 #if NET_4_0
  31 using System;
  32 using System.Collections.Generic;
  33
  34 namespace System.ComponentModel.DataAnnotations
  35 {
  36         [AttributeUsage (AttributeTargets.Property | AttributeTargets.Field, AllowMultiple = false, Inherited = true)]
  37         public sealed class AssociationAttribute : Attribute
  38         {
  39                 static readonly char[] keySplitChars = { ',' };
  40
  41                 IEnumerable <string> otherKeyMembers;
  42                 IEnumerable <string> thisKeyMembers;
  43
  44                 public bool IsForeignKey { get; set; }
  45                 public string Name { get; private set; }
  46                 public string OtherKey { get; private set; }
  47
  48                 public IEnumerable<string> OtherKeyMembers {
  49                         get {
  50                                 if (otherKeyMembers == null)
  51                                         otherKeyMembers = GetKeyMembers (OtherKey);
  52
  53                                 return otherKeyMembers;
  54                         }
  55                 }
  56
  57                 public string ThisKey { get; private set; }
  58
  59                 public IEnumerable<string> ThisKeyMembers {
  60                         get {
  61                                 if (thisKeyMembers == null)
  62                                         thisKeyMembers = GetKeyMembers (ThisKey);
  63
  64                                 return thisKeyMembers;
  65                         }
  66                 }
  67
  68                 public AssociationAttribute (string name, string thisKey, string otherKey)
  69                 {
  70                         this.Name = name;
  71                         this.ThisKey = thisKey;
  72                         this.OtherKey = otherKey;
  73                 }
  74
  75                 IEnumerable <string> GetKeyMembers (string key)
  76                 {
  77                         // .NET emulation
  78                         if (key == null)
  79                                 throw new NullReferenceException (".NET emulation");
  80
  81                         string nows = key.Replace (" ", String.Empty);
  82                         if (nows.Length == 0)
  83                                 return new string[] { String.Empty };
  84
  85                         return nows.Split (keySplitChars);
  86                 }
  87         }
  88 }
  89 #endif