mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/Base/Core/Internal/PropertyEditing/Model/PropertyEntryNameComparer.cs

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4 namespace System.Activities.Presentation.Internal.PropertyEditing.Model
   5 {
   6     using System;
   7     using System.Collections;
   8     using System.Collections.Generic;
   9
  10     using System.Activities.Presentation.PropertyEditing;
  11
  12     // <summary>
  13     // Compares PropertyEntry instances solely on their DisplayName
  14     // </summary>
  15     internal class PropertyEntryNameComparer : IComparer, IComparer<PropertyEntry>
  16     {
  17
  18         public static readonly PropertyEntryNameComparer Instance = new PropertyEntryNameComparer();
  19
  20         private static int CompareCore(object x, object y)
  21         {
  22             ModelPropertyEntry j = x as ModelPropertyEntry;
  23             ModelPropertyEntry k = y as ModelPropertyEntry;
  24
  25             if (j == null && k == null)
  26             {
  27                 return 0;
  28             }
  29             if (j == null)
  30             {
  31                 return -1;
  32             }
  33             if (k == null)
  34             {
  35                 return 1;
  36             }
  37
  38             return string.Compare(j.DisplayName, k.DisplayName, StringComparison.CurrentCulture);
  39         }
  40
  41         // IComparer<PropertyEntry> Members
  42
  43         public int Compare(PropertyEntry x, PropertyEntry y)
  44         {
  45             return CompareCore(x, y);
  46         }
  47
  48
  49         // IComparer Members
  50
  51         public int Compare(object x, object y)
  52         {
  53             return CompareCore(x, y);
  54         }
  55
  56     }
  57 }