class/System.Web/System.Web.UI/DataSourceView.cs

   1 //
   2 // System.Web.UI.DataSourceView
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //      Sanjay Gupta (gsanjay@novell.com)
   7 //
   8 // (C) 2003 Ben Maurer
   9 // (C) 2004-2010 Novell, Inc. (http://www.novell.com)
  10 //
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System.Collections;
  34 using System.Collections.Specialized;
  35 using System.Text;
  36 using System.ComponentModel;
  37
  38 namespace System.Web.UI {
  39         public abstract class DataSourceView
  40         {
  41                 //IDataSource dataSourceOwner;
  42                 string viewName = String.Empty;
  43
  44                 protected DataSourceView (IDataSource owner, string viewName)
  45                 {
  46                         if (owner == null)
  47                                 throw new ArgumentNullException ("owner");
  48
  49                         //this.dataSourceOwner = owner;
  50                         this.viewName = viewName;
  51                         owner.DataSourceChanged += new EventHandler (OnDataSourceChanged);
  52                 }
  53
  54                 void OnDataSourceChanged (object sender, EventArgs e) {
  55                         OnDataSourceViewChanged (EventArgs.Empty);
  56                 }
  57
  58                 public virtual void Delete (IDictionary keys, IDictionary values,
  59                                                 DataSourceViewOperationCallback callBack)
  60                 {
  61                         if (callBack == null)
  62                                 throw new ArgumentNullException ("callBack");
  63
  64                         int rowAffected;
  65                         try {
  66                                 rowAffected = ExecuteDelete (keys, values);
  67                         }
  68                         catch (Exception e) {
  69                                 if (!callBack (0, e))
  70                                         throw;
  71                                 return;
  72                         }
  73                         callBack (rowAffected, null);
  74                 }
  75
  76                 protected virtual int ExecuteDelete(IDictionary keys, IDictionary values)
  77                 {
  78                         throw new NotSupportedException ();
  79                 }
  80
  81                 protected virtual int ExecuteInsert (IDictionary keys)
  82                 {
  83                         throw new NotSupportedException();
  84                 }
  85
  86                 protected internal abstract IEnumerable ExecuteSelect (
  87                                         DataSourceSelectArguments arguments);
  88
  89                 protected virtual int ExecuteUpdate (IDictionary keys, IDictionary values,
  90                                                                 IDictionary oldValues )
  91                 {
  92                         throw new NotSupportedException ();
  93                 }
  94
  95                 public virtual void Insert (IDictionary values,
  96                                         DataSourceViewOperationCallback callBack)
  97                 {
  98                         if (callBack == null)
  99                                 throw new ArgumentNullException("callBack");
 100
 101                         int rowAffected;
 102                         try {
 103                                 rowAffected = ExecuteInsert (values);
 104                         } catch (Exception e) {
 105                                 if (!callBack (0, e))
 106                                         throw;
 107                                 return;
 108                         }
 109
 110                         callBack (rowAffected, null);
 111                 }
 112
 113                 protected virtual void OnDataSourceViewChanged (EventArgs eventArgs)
 114                 {
 115                         if (eventsList != null) {
 116                                 EventHandler evtHandler = eventsList [EventDataSourceViewChanged] as EventHandler;
 117                                 if (evtHandler != null)
 118                                         evtHandler(this, eventArgs);
 119                         }
 120                 }
 121
 122                 protected internal virtual void RaiseUnsupportedCapabilityError (
 123                                                 DataSourceCapabilities capability)
 124                 {
 125                         if ((capability & DataSourceCapabilities.Sort) != 0)
 126                                 if (!CanSort)
 127                                         throw new NotSupportedException ("Sort Capabilites");
 128
 129                         if ((capability & DataSourceCapabilities.Page) != 0)
 130                                 if (!CanPage)
 131                                         throw new NotSupportedException("Page Capabilites");
 132
 133                         if ((capability & DataSourceCapabilities.RetrieveTotalRowCount) != 0)
 134                                 if (!CanRetrieveTotalRowCount)
 135                                         throw new NotSupportedException("RetrieveTotalRowCount Capabilites");
 136
 137                         return;
 138                 }
 139
 140                 public virtual void Select (DataSourceSelectArguments selectArgs,
 141                                                 DataSourceViewSelectCallback callBack)
 142                 {
 143                         if (callBack == null)
 144                                 throw new ArgumentNullException("callBack");
 145
 146                         selectArgs.RaiseUnsupportedCapabilitiesError (this);
 147
 148                         IEnumerable selectList = ExecuteSelect (selectArgs);
 149                         callBack (selectList);
 150                 }
 151
 152                 public virtual void Update(IDictionary keys, IDictionary values,
 153                         IDictionary oldValues, DataSourceViewOperationCallback callBack)
 154                 {
 155                         if (callBack == null)
 156                                 throw new ArgumentNullException ("callBack");
 157
 158                         int rowAffected;
 159                         try {
 160                                 rowAffected = ExecuteUpdate (keys, values, oldValues);
 161                         } catch (Exception e) {
 162                                 if (!callBack (0, e))
 163                                         throw;
 164                                 return;
 165                         }
 166
 167                         callBack (rowAffected, null);
 168                 }
 169
 170                 public virtual bool CanDelete { get { return false; } }
 171                 public virtual bool CanInsert { get { return false; } }
 172                 public virtual bool CanPage { get { return false; } }
 173                 public virtual bool CanRetrieveTotalRowCount { get { return false; } }
 174                 public virtual bool CanSort { get { return false; } }
 175                 public virtual bool CanUpdate { get { return false; } }
 176
 177                 EventHandlerList eventsList;
 178                 protected EventHandlerList Events {
 179                         get {
 180                                 if (eventsList == null)
 181                                         eventsList = new EventHandlerList();
 182
 183                                 return eventsList;
 184                         }
 185                 }
 186
 187                 internal bool HasEvents ()
 188                 {
 189                         return eventsList != null;
 190                 }
 191
 192                 public string Name {
 193                         get { return viewName; }
 194                 }
 195
 196                 static readonly object EventDataSourceViewChanged = new object ();
 197
 198                 public event EventHandler DataSourceViewChanged
 199                 {
 200                         add { Events.AddHandler (EventDataSourceViewChanged, value); }
 201                         remove { Events.RemoveHandler (EventDataSourceViewChanged, value); }
 202                 }
 203
 204         }
 205
 206 }
 207