mcs/class/Managed.Windows.Forms/System.Windows.Forms/BindingContext.cs

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   8 //
   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  13 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  16 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2004-2005 Novell, Inc.
  21 //
  22 // Authors:
  23 //      Peter Bartok    pbartok@novell.com
  24 //      Jackson Harper  jackson@ximian.com
  25
  26
  27 using System.Collections;
  28 using System.Globalization;
  29 using System.ComponentModel;
  30
  31
  32 namespace System.Windows.Forms {
  33
  34         [DefaultEvent("CollectionChanged")]
  35         public class BindingContext : ICollection, IEnumerable {
  36
  37                 private Hashtable managers;
  38
  39                 private class ManagerEntry {
  40
  41                         private object source;
  42                         private WeakReference member_ref;
  43
  44                         private int member_hash;
  45
  46                         public ManagerEntry (object source, string member)
  47                         {
  48                                 this.source = source;
  49                                 if (member == null)
  50                                         member = String.Empty;
  51
  52                                 member_hash = member.ToLower (CultureInfo.InvariantCulture).GetHashCode ();
  53                                 if (member_hash == 0)
  54                                         member_hash = 1;
  55                                 member_ref = new WeakReference (member, false);
  56                         }
  57
  58                         public override bool Equals (object b)
  59                         {
  60                                 ManagerEntry o = (ManagerEntry) b;
  61
  62                                 return (o.source == source && o.member_ref.Target == member_ref.Target);
  63                         }
  64
  65                         public override int GetHashCode ()
  66                         {
  67                                 return member_hash * source.GetHashCode ();
  68                         }
  69
  70                         public override string ToString ()
  71                         {
  72                                 return source.ToString () + " + " + (member_ref.Target == null ? " -- null --" : member_ref.Target.ToString ());
  73                         }
  74                 }
  75
  76                 public BindingContext ()
  77                 {
  78                         managers = new Hashtable ();
  79                 }
  80
  81                 public bool IsReadOnly {
  82                         get {
  83                                 return false;
  84                         }
  85                 }
  86
  87                 public BindingManagerBase this [object dataSource] {
  88                         get {
  89                                 return this [dataSource, String.Empty];
  90                         }
  91                 }
  92
  93                 public BindingManagerBase this [object data_source, string data_member] {
  94                         get {
  95                                 ManagerEntry e = CreateEntry (data_source, data_member);
  96                                 WeakReference wref = managers [e] as WeakReference;
  97
  98                                 if (wref != null && wref.Target != null)
  99                                         return wref.Target as BindingManagerBase;
 100                                 BindingManagerBase res = AddManager (data_source, data_member);
 101                                 return res;
 102                         }
 103                 }
 104
 105                 private BindingManagerBase AddManager (object data_source, string data_member)
 106                 {
 107                         BindingManagerBase res = CreateBindingManager (data_source, data_member);
 108                         managers [CreateEntry (data_source, data_member)] = new WeakReference (res);
 109
 110                         return res;
 111                 }
 112
 113                 private BindingManagerBase CreateBindingManager (object data_source,
 114                         string data_member)
 115                 {
 116                         if (data_source is IList ||
 117                                 data_source is IListSource ||
 118                                 data_source is IBindingList) {
 119                                 CurrencyManager res = new CurrencyManager (data_source);
 120                                 return res;
 121                         }
 122
 123                         return new PropertyManager (data_source, data_member);
 124                 }
 125
 126                 #region Public Instance Methods
 127                 public bool Contains(object dataSource)
 128                 {
 129                         return Contains (dataSource, String.Empty);
 130                 }
 131
 132                 public bool Contains (object dataSource, string dataMember)
 133                 {
 134                         ManagerEntry entry = CreateEntry (dataSource, dataMember);
 135
 136                         return managers.ContainsKey (entry);
 137                 }
 138                 #endregion      // Public Instance Methods
 139
 140                 #region Protected Instance Methods
 141
 142                 protected internal void Add (object dataSource, BindingManagerBase listManager)
 143                 {
 144                         AddCore (dataSource, listManager);
 145                         OnCollectionChanged (new CollectionChangeEventArgs (CollectionChangeAction.Add, dataSource));
 146                 }
 147
 148                 protected virtual void AddCore (object dataSource, BindingManagerBase listManager)
 149                 {
 150                         if (dataSource == null)
 151                                 throw new ArgumentNullException ("dataSource");
 152                         if (listManager == null)
 153                                 throw new ArgumentNullException ("listManager");
 154                         managers.Add (CreateEntry (dataSource, String.Empty), new WeakReference (listManager));
 155                 }
 156
 157                 protected internal void Clear ()
 158                 {
 159                         ClearCore();
 160                         OnCollectionChanged (new CollectionChangeEventArgs (CollectionChangeAction.Refresh, null));
 161                 }
 162
 163                 protected virtual void ClearCore ()
 164                 {
 165                         managers.Clear ();
 166                 }
 167
 168                 protected virtual void OnCollectionChanged(System.ComponentModel.CollectionChangeEventArgs ccevent)
 169                 {
 170                         if (CollectionChanged != null) {
 171                                 CollectionChanged (this, ccevent);
 172                         }
 173                 }
 174
 175                 protected internal void Remove (object dataSource)
 176                 {
 177                         RemoveCore (dataSource);
 178                         OnCollectionChanged (new CollectionChangeEventArgs (CollectionChangeAction.Remove, dataSource));
 179                 }
 180
 181                 protected virtual void RemoveCore (object dataSource)
 182                 {
 183                         managers.Remove (CreateEntry (dataSource, String.Empty));
 184                 }
 185                 #endregion      // Protected Instance Methods
 186
 187                 #region Events
 188                 public event CollectionChangeEventHandler CollectionChanged;
 189                 #endregion      // Events
 190
 191                 #region ICollection Interfaces
 192                 void ICollection.CopyTo (Array array, int index)
 193                 {
 194                         managers.CopyTo (array, index);
 195                 }
 196
 197                 int ICollection.Count {
 198                         get {
 199                                 return managers.Count;
 200                         }
 201                 }
 202
 203                 bool ICollection.IsSynchronized {
 204                         get {
 205                                 return false;
 206                         }
 207                 }
 208
 209                 object ICollection.SyncRoot {
 210                         get {
 211                                 return null;
 212                         }
 213                 }
 214
 215                 #endregion      // ICollection Interfaces
 216
 217                 #region IEnumerable Interfaces
 218                 [MonoTODO]
 219                 IEnumerator IEnumerable.GetEnumerator() {
 220                         throw new NotImplementedException();
 221                 }
 222                 #endregion      // IEnumerable Interfaces
 223
 224                 private ManagerEntry CreateEntry (object dataSource, string dataMember)
 225                 {
 226                         return new ManagerEntry (dataSource, dataMember);
 227                 }
 228         }
 229 }