mcs/class/System.Web/System.Web.UI/StateManagedCollection.cs

   1 //
   2 // System.Web.UI.StateManagedCollection
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //
   7 // (C) 2003 Ben Maurer
   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
  31 #if NET_2_0
  32 using System.Collections;
  33 using System.Collections.Specialized;
  34 using System.Text;
  35
  36 namespace System.Web.UI {
  37         public abstract class StateManagedCollection : IList, IStateManager {
  38
  39                 protected abstract object CreateKnownType (int index);
  40                 protected abstract void SetDirtyObject (object o);
  41                 protected virtual Type [] GetKnownTypes ()
  42                 {
  43                         return null;
  44                 }
  45
  46                 #region OnXXX
  47                 protected virtual void OnClear ()
  48                 {
  49                 }
  50
  51                 protected virtual void OnClearComplete ()
  52                 {
  53                 }
  54
  55                 protected virtual void OnInsert (int index, object value)
  56                 {
  57                 }
  58
  59                 protected virtual void OnInsertComplete (int index, object value)
  60                 {
  61                 }
  62
  63                 protected virtual void OnRemove (int index, object value)
  64                 {
  65                 }
  66
  67                 protected virtual void OnRemoveComplete (int index, object value)
  68                 {
  69                 }
  70
  71                 protected virtual void OnValidate (object value)
  72                 {
  73                         if (value == null)
  74                                 throw new ArgumentNullException ("value");
  75                 }
  76                 #endregion
  77
  78                 #region IStateManager
  79                 void IStateManager.LoadViewState (object savedState)
  80                 {
  81                         if (savedState == null) return;
  82
  83                         int pos = -1;
  84                         foreach (Pair p in (ArrayList)savedState) {
  85                                 pos ++;
  86
  87                                 if (p == null)
  88                                         continue;
  89                                 IStateManager itm;
  90
  91                                 if (p.Second is Type)
  92                                         itm = (IStateManager) Activator.CreateInstance ((Type) p.Second);
  93                                 else
  94                                         itm = (IStateManager) CreateKnownType ((int) p.Second);
  95
  96                                 if (isTrackingViewState)
  97                                         itm.TrackViewState ();
  98
  99                                 itm.LoadViewState (p.First);
 100
 101                                 if (pos >= Count)
 102                                         items.Add (itm);
 103                                 else
 104                                         items [pos] = itm;
 105
 106                         }
 107                 }
 108
 109                 object IStateManager.SaveViewState ()
 110                 {
 111                         ArrayList saved = new ArrayList ();
 112                         Type [] knownTypes = GetKnownTypes ();
 113                         bool allNull = true;
 114
 115                         foreach (IStateManager itm in items) {
 116                                 object state = itm.SaveViewState ();
 117                                 if (state == null && !saveEverything) {
 118                                         saved.Add (null);
 119                                         continue;
 120                                 }
 121
 122                                 Pair p = new Pair ();
 123                                 p.First = state;
 124
 125                                 Type t = itm.GetType ();
 126                                 int idx = -1;
 127                                 if (knownTypes != null)
 128                                         idx = Array.IndexOf (knownTypes, t);
 129
 130                                 if (idx != -1)
 131                                         p.Second = idx;
 132                                 else
 133                                         p.Second = t;
 134
 135                                 saved.Add (p);
 136                                 allNull = false;
 137                         }
 138
 139                         if (allNull) return null;
 140                         else return saved;
 141                 }
 142
 143                 void IStateManager.TrackViewState ()
 144                 {
 145                         isTrackingViewState = true;
 146
 147                         foreach (IStateManager i in items)
 148                                 i.TrackViewState ();
 149                 }
 150
 151                 bool isTrackingViewState;
 152                 bool IStateManager.IsTrackingViewState {
 153                         get { return isTrackingViewState; }
 154                 }
 155                 #endregion
 156
 157                 #region ICollection, IList, IEnumerable
 158
 159                 public void Clear ()
 160                 {
 161                         this.OnClear ();
 162                         items.Clear ();
 163                         this.OnClearComplete ();
 164
 165                         SetSaveEverything ();
 166                 }
 167
 168                 public int IndexOf (object o)
 169                 {
 170                         if (o == null)
 171                                 return -1;
 172                         return items.IndexOf (o);
 173                 }
 174
 175                 public bool Contains (object o)
 176                 {
 177                         return o != null && items.Contains (o);
 178                 }
 179
 180                 public IEnumerator GetEnumerator ()
 181                 {
 182                         return items.GetEnumerator ();
 183                 }
 184
 185                 void System.Collections.ICollection.CopyTo (Array array, int index)
 186                 {
 187                         items.CopyTo (array, index);
 188                 }
 189
 190                 IEnumerator IEnumerable.GetEnumerator ()
 191                 {
 192                         return GetEnumerator ();
 193                 }
 194
 195                 int IList.Add (object value)
 196                 {
 197                         OnValidate(value);
 198                         if (isTrackingViewState) {
 199                                 ((IStateManager) value).TrackViewState ();
 200                                 SetDirtyObject (value);
 201                         }
 202
 203                         OnInsert (-1, value);
 204                         items.Add (value);
 205                         OnInsertComplete (-1, value);
 206
 207                         return Count - 1;
 208                 }
 209
 210                 void IList.Insert (int index, object value)
 211                 {
 212                         OnValidate(value);
 213                         if (isTrackingViewState) {
 214                                 ((IStateManager) value).TrackViewState ();
 215                                 SetDirtyObject (value);
 216                         }
 217
 218                         OnInsert (index, value);
 219                         items.Insert (index, value);
 220                         OnInsertComplete(index, value);
 221
 222                         SetSaveEverything ();
 223                 }
 224
 225                 void IList.Remove (object value)
 226                 {
 227                         if (value == null)
 228                                 return;
 229                         OnValidate (value);
 230                         ((IList)this).RemoveAt (IndexOf (value));
 231                 }
 232                 void IList.RemoveAt (int index)
 233                 {
 234                         object o = items [index];
 235
 236                         OnRemove (index, o);
 237                         items.RemoveAt (index);
 238                         OnRemoveComplete(index, o);
 239
 240                         SetSaveEverything ();
 241                 }
 242
 243                 void IList.Clear ()
 244                 {
 245                         this.Clear ();
 246                 }
 247
 248                 bool IList.Contains (object value)
 249                 {
 250                         if (value == null)
 251                                 return false;
 252
 253                         OnValidate (value);
 254                         return Contains (value);
 255                 }
 256
 257                 int IList.IndexOf (object value)
 258                 {
 259                         if (value == null)
 260                                 return -1;
 261
 262                         OnValidate (value);
 263                         return IndexOf (value);
 264                 }
 265
 266                 public int Count {
 267                         get { return items.Count; }
 268                 }
 269
 270                 int ICollection.Count {
 271                         get { return items.Count; }
 272                 }
 273
 274                 bool ICollection.IsSynchronized {
 275                         get { return false; }
 276                 }
 277
 278                 object ICollection.SyncRoot {
 279                         get { return this; }
 280                 }
 281
 282                 bool IList.IsFixedSize {
 283                         get { return false; }
 284                 }
 285
 286                 bool IList.IsReadOnly {
 287                         get { return false; }
 288                 }
 289
 290                 object IList.this [int index] {
 291                         get { return items [index]; }
 292                         set {
 293                                 if (index < 0 || index >= Count)
 294                                         throw new ArgumentOutOfRangeException ("index");
 295
 296                                 OnValidate (value);
 297                                 if (isTrackingViewState) {
 298                                         ((IStateManager) value).TrackViewState ();
 299                                         SetDirtyObject (value);
 300                                 }
 301
 302                                 items [index] = value;
 303                         }
 304                 }
 305                 #endregion
 306
 307                 ArrayList items = new ArrayList ();
 308
 309                 bool saveEverything = false;
 310                 void SetSaveEverything ()
 311                 {
 312                         if (isTrackingViewState)
 313                                 saveEverything = true;
 314                 }
 315         }
 316 }
 317 #endif
 318