mcs/class/System.Web/System.Web.UI.WebControls/ListControl.cs

   1 //
   2 // System.Web.UI.WebControls.ListControl.cs
   3 //
   4 // Authors:
   5 //   Gaurav Vaish (gvaish@iitk.ac.in)
   6 //   Andreas Nahr (ClassDevelopment@A-SoftTech.com)
   7 //
   8 // (C) Gaurav Vaish (2002)
   9 // (C) 2003 Andreas Nahr
  10 //
  11 \r
  12 using System;\r
  13 using System.Collections;\r
  14 using System.ComponentModel;
  15 using System.ComponentModel.Design;\r
  16 using System.Web;\r
  17 using System.Web.UI;\r
  18 using System.Web.Util;\r
  19 \r
  20 namespace System.Web.UI.WebControls\r
  21 {\r
  22         [DefaultEvent("SelectedIndexChanged")]\r
  23         [DefaultProperty("DataSource")]\r
  24         [Designer ("System.Web.UI.Design.WebControls.ListControlDesigner, " + Consts.AssemblySystem_Design, typeof (IDesigner))]\r
  25         [DataBindingHandler("System.Web.UI.Design.ListControlDataBindingHandler, " + Consts.AssemblySystem_Design)]\r
  26         [ParseChildren(true, "Items")]\r
  27         public abstract class ListControl: WebControl\r
  28         {\r
  29                 private static readonly object SelectedIndexChangedEvent = new object();\r
  30 \r
  31                 private object             dataSource;\r
  32                 private ListItemCollection items;\r
  33 \r
  34                 private int cachedSelectedIndex = -1;\r
  35                 private string cachedSelectedValue;
  36 \r
  37                 public ListControl(): base(HtmlTextWriterTag.Select)\r
  38                 {\r
  39                 }\r
  40
  41                 [WebCategory ("Action")]
  42                 [WebSysDescription ("Raised when the selected index entry has changed.")]\r
  43                 public event EventHandler SelectedIndexChanged\r
  44                 {\r
  45                         add\r
  46                         {\r
  47                                 Events.AddHandler(SelectedIndexChangedEvent, value);\r
  48                         }\r
  49                         remove\r
  50                         {\r
  51                                 Events.RemoveHandler(SelectedIndexChangedEvent, value);\r
  52                         }\r
  53                 }\r
  54
  55                 [DefaultValue (false), WebCategory ("Behavior")]
  56                 [WebSysDescription ("The control automatically posts back after changing the text.")]\r
  57                 public virtual bool AutoPostBack\r
  58                 {\r
  59                         get\r
  60                         {\r
  61                                 object o = ViewState["AutoPostBack"];\r
  62                                 if(o!=null)\r
  63                                         return (bool)o;\r
  64                                 return false;\r
  65                         }\r
  66                         set\r
  67                         {\r
  68                                 ViewState["AutoPostBack"] = value;\r
  69                         }\r
  70                 }\r
  71
  72                 [DefaultValue (""), WebCategory ("Data")]
  73                 [WebSysDescription ("The name of the table that is used for binding when a DataSource is specified.")]\r
  74                 public virtual string DataMember\r
  75                 {\r
  76                         get\r
  77                         {\r
  78                                 object o = ViewState["DataMember"];\r
  79                                 if(o!=null)\r
  80                                         return (string)o;\r
  81                                 return String.Empty;\r
  82                         }\r
  83                         set\r
  84                         {\r
  85                                 ViewState["DataMember"] = value;\r
  86                         }\r
  87                 }\r
  88
  89
  90                 [DefaultValue (null), Bindable (true), WebCategory ("Data")]
  91                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
  92                 [WebSysDescription ("The DataSource that is used for data-binding.")]\r
  93                 public virtual object DataSource\r
  94                 {\r
  95                         get\r
  96                         {\r
  97                                 return dataSource;\r
  98                         }\r
  99                         set\r
 100                         {\r
 101                                 if(value == null || value is IListSource || value is IEnumerable) {
 102                                         dataSource = value;
 103                                         return;
 104                                 }
 105                                 throw new ArgumentException(HttpRuntime.FormatResourceString(ID, "Invalid DataSource Type"));\r
 106                         }\r
 107                 }\r
 108
 109                 [DefaultValue (""), WebCategory ("Data")]
 110                 [WebSysDescription ("The field in the datatable that provides the text entry.")]\r
 111                 public virtual string DataTextField\r
 112                 {\r
 113                         get\r
 114                         {\r
 115                                 object o = ViewState["DataTextField"];\r
 116                                 if(o!=null)\r
 117                                         return (string)o;\r
 118                                 return String.Empty;\r
 119                         }\r
 120                         set\r
 121                         {\r
 122                                 ViewState["DataTextField"] = value;\r
 123                         }\r
 124                 }\r
 125
 126                 [DefaultValue (""), WebCategory ("Data")]
 127                 [WebSysDescription ("Specifies a formatting rule for the texts that are returned.")]\r
 128                 public virtual string DataTextFormatString\r
 129                 {\r
 130                         get\r
 131                         {\r
 132                                 object o = ViewState["DataTextFormatString"];\r
 133                                 if(o!=null)\r
 134                                         return (string)o;\r
 135                                 return String.Empty;\r
 136                         }\r
 137                         set\r
 138                         {\r
 139                                 ViewState["DataTextFormatString"] = value;\r
 140                         }\r
 141                 }\r
 142
 143                 [DefaultValue (""), WebCategory ("Data")]
 144                 [WebSysDescription ("The field in the datatable that provides the entry value.")]\r
 145                 public virtual string DataValueField\r
 146                 {\r
 147                         get\r
 148                         {\r
 149                                 object o = ViewState["DataValueField"];\r
 150                                 if(o!=null)\r
 151                                         return (string)o;\r
 152                                 return String.Empty;\r
 153                         }\r
 154                         set\r
 155                         {\r
 156                                 ViewState["DataValueField"] = value;\r
 157                         }\r
 158                 }\r
 159
 160                 [DefaultValue (null), MergableProperty (false), WebCategory ("Misc")]
 161                 [PersistenceMode (PersistenceMode.InnerDefaultProperty)]
 162                 [WebSysDescription ("A collection of all items contained in this list.")]\r
 163                 public virtual ListItemCollection Items\r
 164                 {\r
 165                         get\r
 166                         {\r
 167                                 if(items==null)\r
 168                                 {\r
 169                                         items = new ListItemCollection();\r
 170                                         if(IsTrackingViewState)\r
 171                                         {\r
 172                                                 items.TrackViewState();\r
 173                                         }\r
 174                                 }\r
 175                                 return items;\r
 176                         }\r
 177                 }\r
 178
 179                 [DefaultValue (0), Bindable (true), WebCategory ("Misc")]
 180                 [Browsable (false), DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 181                 [WebSysDescription ("The index number of the currently selected ListItem.")]\r
 182                 public virtual int SelectedIndex\r
 183                 {\r
 184                         get {\r
 185                                 ListItemCollection items = Items;\r
 186                                 int last = items.Count;\r
 187                                 for (int i = 0; i < last; i++) {\r
 188                                         if (items [i].Selected)\r
 189                                                 return i;\r
 190                                 }\r
 191                                 return -1;\r
 192                         }\r
 193                         set {\r
 194                                 if (value < -1 || value > Items.Count)\r
 195                                         throw new ArgumentOutOfRangeException ();\r
 196 \r
 197                                 ClearSelection ();\r
 198                                 if (value != -1)\r
 199                                         Items [value].Selected = true;\r
 200                         }\r
 201                 }\r
 202
 203                 [DefaultValue (null), WebCategory ("Misc")]
 204                 [Browsable (false), DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 205                 [WebSysDescription ("The currently selected ListItem.")]\r
 206                 public virtual ListItem SelectedItem\r
 207                 {\r
 208                         get\r
 209                         {\r
 210                                 int idx = SelectedIndex;\r
 211                                 if (idx < 0)\r
 212                                         return null;\r
 213 \r
 214                                 return Items [idx];\r
 215                         }\r
 216                 }\r
 217 \r
 218 #if NET_1_1
 219                 [DefaultValue (""), Bindable (true), WebCategory ("Misc")]
 220                 [Browsable (false), DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 221                 [WebSysDescription ("The value of the currently selected ListItem.")]\r
 222                 public virtual string SelectedValue {\r
 223                         get {\r
 224                                 int idx = SelectedIndex;\r
 225                                 if (idx == -1)\r
 226                                         return "";\r
 227 \r
 228                                 return Items [idx].Value;\r
 229                         }\r
 230 \r
 231                         set {\r
 232                                 ListItem item = null;\r
 233 \r
 234                                 if (value != null) {\r
 235                                         if (Items.Count > 0) {
 236                                                 item = Items.FindByValue (value);
 237                                                 if (item == null)
 238                                                         throw new ArgumentOutOfRangeException ("value");
 239                                         } else {
 240                                                 cachedSelectedValue = value;
 241                                                 return;
 242                                         }
 243                                 }\r
 244 \r
 245                                 ClearSelection ();\r
 246                                 if (item != null)\r
 247                                         item.Selected = true;\r
 248                         }\r
 249                 }\r
 250 #endif\r
 251                 \r
 252                 internal virtual ArrayList SelectedIndices\r
 253                 {\r
 254                         get\r
 255                         {\r
 256                                 ArrayList si = new ArrayList();\r
 257                                 for(int i=0; i < Items.Count; i++)\r
 258                                 {\r
 259                                         if(Items[i].Selected)\r
 260                                                 si.Add(i);\r
 261                                 }\r
 262                                 return si;\r
 263                         }\r
 264                 }\r
 265 \r
 266                 internal void Select(ArrayList indices)\r
 267                 {\r
 268                         ClearSelection();\r
 269                         foreach(object intObj in indices)\r
 270                         {\r
 271                                 int index = (int)intObj;\r
 272                                 if(index >= 0 && index < Items.Count)\r
 273                                         Items[index].Selected = true;\r
 274                         }\r
 275                 }\r
 276 \r
 277                 public virtual void ClearSelection()\r
 278                 {\r
 279                         for(int i=0; i < Items.Count; i++)\r
 280                         {\r
 281                                 Items[i].Selected = false;\r
 282                         }\r
 283                 }\r
 284 \r
 285                 protected override void LoadViewState(object savedState)\r
 286                 {\r
 287                         //Order: BaseClass, Items (Collection), Indices\r
 288                         if(savedState != null && savedState is Triplet)\r
 289                         {\r
 290                                 Triplet state = (Triplet)savedState;\r
 291                                 base.LoadViewState(state.First);\r
 292                                 Items.LoadViewState(state.Second);\r
 293                                 object indices = state.Third;\r
 294                                 if(indices != null)\r
 295                                 {\r
 296                                         Select((ArrayList)indices);\r
 297                                 }\r
 298                         }\r
 299                 }\r
 300 \r
 301                 protected override void OnDataBinding(EventArgs e)\r
 302                 {\r
 303                         base.OnDataBinding(e);\r
 304                         IEnumerable ds = DataSourceHelper.GetResolvedDataSource (DataSource, DataMember);\r
 305 \r
 306                         if(ds != null) {\r
 307                                 string dtf = DataTextField;\r
 308                                 string dvf = DataValueField;\r
 309                                 string dtfs = DataTextFormatString;\r
 310                                 if (dtfs.Length == 0)\r
 311                                         dtfs = "{0}";\r
 312 \r
 313                                 Items.Clear();\r
 314 \r
 315                                 bool dontUseProperties = (dtf.Length == 0 && dvf.Length == 0);\r
 316 \r
 317                                 foreach (object current in ds) {\r
 318                                         ListItem li = new ListItem();\r
 319                                         if (dontUseProperties){\r
 320                                                 li.Text  = String.Format (dtfs, current);\r
 321                                                 li.Value = current.ToString ();\r
 322                                                 Items.Add (li);\r
 323                                                 continue;\r
 324                                         }\r
 325 \r
 326                                         object o;\r
 327                                         if (dtf.Length > 0) {\r
 328                                                 o = DataBinder.GetPropertyValue (current, dtf, dtfs);\r
 329                                                 li.Text = o.ToString ();\r
 330                                         }\r
 331 \r
 332                                         if (dvf.Length > 0) {\r
 333                                                 o = DataBinder.GetPropertyValue (current, dvf, null);\r
 334                                                 li.Value = o.ToString ();\r
 335                                         }\r
 336 \r
 337                                         Items.Add(li);\r
 338                                 }\r
 339                         }\r
 340
 341                         if (cachedSelectedValue != null) {
 342                                 int index = Items.FindByValueInternal (cachedSelectedValue);
 343                                 if (index == -1)
 344                                         throw new ArgumentOutOfRangeException("value");
 345
 346                                 if (cachedSelectedIndex != -1 && cachedSelectedIndex != index)
 347                                         throw new ArgumentException(HttpRuntime.FormatResourceString(
 348                                                 "Attributes_mutually_exclusive", "Selected Index", "Selected Value"));
 349
 350                                 SelectedIndex = index;
 351                                 cachedSelectedIndex = -1;
 352                                 cachedSelectedValue = null;
 353                                 return;
 354                         }
 355
 356                         if (cachedSelectedIndex != -1) {\r
 357                                 SelectedIndex = cachedSelectedIndex;\r
 358                                 cachedSelectedIndex = -1;\r
 359                         }\r
 360                 }\r
 361 \r
 362                 protected virtual void OnSelectedIndexChanged(EventArgs e)\r
 363                 {\r
 364                         if(Events!=null)\r
 365                                 {\r
 366                                         EventHandler eh = (EventHandler)(Events[SelectedIndexChangedEvent]);\r
 367                                         if(eh!=null)\r
 368                                                 eh(this, e);\r
 369                                 }\r
 370                 }\r
 371 \r
 372                 protected override void OnPreRender (EventArgs e)\r
 373                 {\r
 374                         base.OnPreRender(e);\r
 375                 }\r
 376 \r
 377                 protected override object SaveViewState()\r
 378                 {\r
 379                         //Order: BaseClass, Items (Collection), Indices\r
 380                         object vs = base.SaveViewState();\r
 381                         object itemSvs = Items.SaveViewState();\r
 382                         object indices = null;\r
 383                         if (SaveSelectedIndicesViewState)\r
 384                                 indices = SelectedIndices;\r
 385 \r
 386                         if (vs != null || itemSvs != null || indices != null)\r
 387                                 return new Triplet(vs, itemSvs, indices);\r
 388 \r
 389                         return null;\r
 390                 }\r
 391 \r
 392                 protected override void TrackViewState()\r
 393                 {\r
 394                         base.TrackViewState();\r
 395                         Items.TrackViewState();\r
 396                 }\r
 397 \r
 398                 private bool SaveSelectedIndicesViewState {\r
 399                         get {\r
 400                                 if (Events[SelectedIndexChangedEvent] == null && Enabled && Visible) {\r
 401                                         Type t = GetType();\r
 402                                         // If I am a derivative, let it take of storing the selected indices.\r
 403                                         if (t == typeof(DropDownList) || t == typeof(ListBox) ||\r
 404                                             t == typeof(CheckBoxList) || t == typeof(RadioButtonList))\r
 405                                                 return false;\r
 406                                 }\r
 407                                 return true;\r
 408                         }\r
 409                 }\r
 410         }\r
 411 }\r