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

   1 //
   2 // System.Web.UI.WebControls.TreeNode.cs
   3 //
   4 // Authors:
   5 //      Lluis Sanchez Gual (lluis@novell.com)
   6 //
   7 // (C) 2004 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  29 //
  30
  31
  32 using System;
  33 using System.Collections;
  34 using System.Text;
  35 using System.ComponentModel;
  36 using System.Web.UI;
  37
  38 namespace System.Web.UI.WebControls
  39 {
  40         [ParseChildrenAttribute (true, "ChildNodes")]
  41         public class TreeNode: IStateManager, ICloneable
  42         {
  43                 StateBag ViewState = new StateBag ();
  44                 TreeNodeCollection nodes;
  45                 bool marked;
  46                 TreeView tree;
  47                 TreeNode parent;
  48                 int index;
  49                 string path;
  50                 int depth = -1;
  51
  52                 object dataItem;
  53                 IHierarchyData hierarchyData;
  54
  55                 bool gotBinding;
  56                 TreeNodeBinding binding;
  57                 PropertyDescriptorCollection boundProperties;
  58                 bool populating;
  59                 bool hadChildrenBeforePopulating;
  60
  61                 internal TreeNode (TreeView tree)
  62                 {
  63                         Tree = tree;
  64                 }
  65
  66                 public TreeNode ()
  67                 {
  68                 }
  69
  70                 public TreeNode (string text)
  71                 {
  72                         Text = text;
  73                 }
  74
  75                 public TreeNode (string text, string value)
  76                 {
  77                         Text = text;
  78                         Value = value;
  79                 }
  80
  81                 public TreeNode (string text, string value, string imageUrl)
  82                 {
  83                         Text = text;
  84                         Value = value;
  85                         ImageUrl = imageUrl;
  86                 }
  87
  88                 public TreeNode (string text, string value, string imageUrl, string navigateUrl, string target)
  89                 {
  90                         Text = text;
  91                         Value = value;
  92                         ImageUrl = imageUrl;
  93                         NavigateUrl = navigateUrl;
  94                         Target = target;
  95                 }
  96
  97                 [MonoTODO ("Not implemented")]
  98                 protected TreeNode (TreeView owner, bool isRoot)
  99                 {
 100                         throw new NotImplementedException ();
 101                 }
 102
 103                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 104                 [Browsable (false)]
 105                 public int Depth {
 106                         get {
 107                                 if (depth != -1) return depth;
 108                                 depth = 0;
 109                                 TreeNode nod = parent;
 110                                 while (nod != null) {
 111                                         depth++;
 112                                         nod = nod.parent;
 113                                 }
 114                                 return depth;
 115                         }
 116                 }
 117
 118                 void ResetPathData ()
 119                 {
 120                         path = null;
 121                         depth = -1;
 122                         gotBinding = false;
 123                         if (nodes != null) {
 124                                 foreach (TreeNode node in nodes)
 125                                         node.ResetPathData ();
 126                         }
 127                 }
 128
 129                 internal TreeView Tree {
 130                         get { return tree; }
 131                         set {
 132                                 if (SelectedFlag) {
 133                                         if (value != null)
 134                                                 value.SetSelectedNode (this, false);
 135                                 }
 136                                 tree = value;
 137                                 if (nodes != null)
 138                                         nodes.SetTree (tree);
 139                                 ResetPathData ();
 140                                 if (PopulateOnDemand && !Populated && Expanded.HasValue && Expanded.Value)
 141                                         Populate ();
 142                         }
 143                 }
 144
 145                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 146                 [DefaultValue (false)]
 147                 [Browsable (false)]
 148                 public bool DataBound {
 149                         get { return ViewState ["DataBound"] == null ? false : (bool) ViewState ["DataBound"]; }
 150                         private set { ViewState ["DataBound"] = value; }
 151                 }
 152
 153                 [DefaultValue (null)]
 154                 [Browsable (false)]
 155                 public object DataItem {
 156                         get { return dataItem; }
 157                 }
 158
 159                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 160                 [DefaultValue ("")]
 161                 [Browsable (false)]
 162                 public string DataPath {
 163                         get { return ViewState ["DataPath"] == null ? String.Empty : (String) ViewState ["DataPath"]; }
 164                         private set { ViewState ["DataPath"] = value; }
 165                 }
 166
 167                 [DefaultValue (false)]
 168                 public bool Checked {
 169                         get {
 170                                 object o = ViewState ["Checked"];
 171                                 if (o != null) return (bool)o;
 172                                 return false;
 173                         }
 174                         set {
 175                                 ViewState ["Checked"] = value;
 176                                 if (tree != null)
 177                                         tree.NotifyCheckChanged (this);
 178                         }
 179                 }
 180
 181                 [DefaultValue (null)]
 182                 [MergableProperty (false)]
 183                 [Browsable (false)]
 184                 [PersistenceMode (PersistenceMode.InnerDefaultProperty)]
 185                 public TreeNodeCollection ChildNodes {
 186                         get {
 187                                 if (nodes == null) {
 188                                         nodes = new TreeNodeCollection (this);
 189
 190                                         if (IsTrackingViewState)
 191                                                 ((IStateManager)nodes).TrackViewState();
 192                                 }
 193                                 return nodes;
 194                         }
 195                 }
 196
 197                 [DefaultValue (null)]
 198                 public bool? Expanded {
 199                         get {
 200                                 object o = ViewState ["Expanded"];
 201                                 return (bool?)o;
 202                         }
 203                         set {
 204                                 bool? current = (bool?) ViewState ["Expanded"];
 205                                 if (current == value)
 206                                         return;
 207                                 ViewState ["Expanded"] = value;
 208                                 if (tree != null)
 209                                         tree.NotifyExpandedChanged (this);
 210                                 if (PopulateOnDemand && !Populated && value.HasValue && value.Value)
 211                                         Populate ();
 212                         }
 213                 }
 214
 215                 [Localizable (true)]
 216                 [DefaultValue ("")]
 217                 public string ImageToolTip {
 218                         get {
 219                                 object o = ViewState ["ImageToolTip"];
 220                                 if (o != null)
 221                                         return (string)o;
 222                                 return String.Empty;
 223                         }
 224                         set { ViewState ["ImageToolTip"] = value; }
 225                 }
 226
 227                 [DefaultValue ("")]
 228                 [UrlProperty]
 229                 [Editor ("System.Web.UI.Design.ImageUrlEditor, " + Consts.AssemblySystem_Design, typeof (System.Drawing.Design.UITypeEditor))]
 230                 public string ImageUrl {
 231                         get {
 232                                 object o = ViewState ["ImageUrl"];
 233                                 if (o != null)
 234                                         return (string)o;
 235                                 return String.Empty;
 236                         }
 237                         set { ViewState ["ImageUrl"] = value; }
 238                 }
 239
 240                 [DefaultValue ("")]
 241                 [UrlProperty]
 242                 [Editor ("System.Web.UI.Design.UrlEditor, " + Consts.AssemblySystem_Design, typeof (System.Drawing.Design.UITypeEditor))]
 243                 public string NavigateUrl {
 244                         get {
 245                                 object o = ViewState ["NavigateUrl"];
 246                                 if (o != null)
 247                                         return (string)o;
 248                                 return String.Empty;
 249                         }
 250                         set { ViewState ["NavigateUrl"] = value; }
 251                 }
 252
 253                 internal bool HadChildrenBeforePopulating {
 254                         get { return hadChildrenBeforePopulating; }
 255                         set {
 256                                 if (populating)
 257                                         return;
 258
 259                                 hadChildrenBeforePopulating = value;
 260                         }
 261                 }
 262
 263                 [DefaultValue (false)]
 264                 public bool PopulateOnDemand {
 265                         get {
 266                                 object o = ViewState ["PopulateOnDemand"];
 267                                 if (o != null)
 268                                         return (bool)o;
 269                                 return false;
 270                         }
 271                         set {
 272                                 ViewState ["PopulateOnDemand"] = value;
 273                                 if (value && nodes != null && nodes.Count > 0)
 274                                         HadChildrenBeforePopulating = true;
 275                                 else
 276                                         HadChildrenBeforePopulating = false;
 277                         }
 278                 }
 279
 280                 [DefaultValue (TreeNodeSelectAction.Select)]
 281                 public TreeNodeSelectAction SelectAction {
 282                         get {
 283                                 object o = ViewState ["SelectAction"];
 284                                 if (o != null)
 285                                         return (TreeNodeSelectAction)o;
 286                                 return TreeNodeSelectAction.Select;
 287                         }
 288                         set { ViewState ["SelectAction"] = value; }
 289                 }
 290
 291                 [DefaultValue (null)]
 292                 public bool? ShowCheckBox {
 293                         get {
 294                                 object o = ViewState ["ShowCheckBox"];
 295                                 return (bool?)o;
 296                         }
 297                         set { ViewState ["ShowCheckBox"] = value; }
 298                 }
 299
 300                 internal bool ShowCheckBoxInternal {
 301                         get {
 302                                 if (ShowCheckBox.HasValue)
 303                                         return ShowCheckBox.Value;
 304                                 else
 305                                         return (Tree.ShowCheckBoxes == TreeNodeTypes.All) ||
 306                                                  ((Tree.ShowCheckBoxes & TreeNodeTypes.Leaf) > 0 && IsLeafNode) ||
 307                                                  ((Tree.ShowCheckBoxes & TreeNodeTypes.Parent) > 0 && IsParentNode && Parent != null) ||
 308                                                  ((Tree.ShowCheckBoxes & TreeNodeTypes.Root) > 0 && Parent == null && ChildNodes.Count > 0);
 309                         }
 310                 }
 311
 312                 [DefaultValue ("")]
 313                 public string Target {
 314                         get {
 315                                 object o = ViewState ["Target"];
 316                                 if(o != null)
 317                                         return (string)o;
 318                                 return String.Empty;
 319                         }
 320                         set { ViewState ["Target"] = value; }
 321                 }
 322
 323                 [Localizable (true)]
 324                 [DefaultValue ("")]
 325                 [WebSysDescription ("The display text of the tree node.")]
 326                 public string Text {
 327                         get {
 328                                 object o = ViewState ["Text"];
 329                                 if (o == null)
 330                                         o = ViewState ["Value"];
 331                                 if (o != null)
 332                                         return (string)o;
 333                                 return String.Empty;
 334                         }
 335                         set { ViewState ["Text"] = value; }
 336                 }
 337
 338                 [Localizable (true)]
 339                 [DefaultValue ("")]
 340                 public string ToolTip {
 341                         get {
 342                                 object o = ViewState ["ToolTip"];
 343                                 if(o != null)
 344                                         return (string)o;
 345                                 return String.Empty;
 346                         }
 347                         set { ViewState ["ToolTip"] = value; }
 348                 }
 349
 350                 [Localizable (true)]
 351                 [DefaultValue ("")]
 352                 public string Value {
 353                         get {
 354                                 object o = ViewState ["Value"];
 355                                 if (o == null)
 356                                         o = ViewState ["Text"];
 357                                 if(o != null)
 358                                         return (string)o;
 359                                 return String.Empty;
 360                         }
 361                         set { ViewState ["Value"] = value; }
 362                 }
 363
 364                 [DefaultValue (false)]
 365                 public bool Selected {
 366                         get { return SelectedFlag; }
 367                         set {
 368                                 SelectedFlag = value;
 369
 370                                 if (tree != null) {
 371                                         if (!value && tree.SelectedNode == this)
 372                                                 tree.SetSelectedNode (null, false);
 373                                         else if (value)
 374                                                 tree.SetSelectedNode (this, false);
 375                                 }
 376                         }
 377                 }
 378
 379                 internal virtual bool SelectedFlag {
 380                         get {
 381                                 object o = ViewState ["Selected"];
 382                                 if(o != null)
 383                                         return (bool)o;
 384                                 return false;
 385                         }
 386                         set { ViewState ["Selected"] = value; }
 387                 }
 388
 389                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 390                 [Browsable (false)]
 391                 public TreeNode Parent {
 392                         get { return parent; }
 393                 }
 394
 395                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 396                 [Browsable (false)]
 397                 public string ValuePath {
 398                         get {
 399                                 if (tree == null) return Value;
 400
 401                                 StringBuilder sb = new StringBuilder (Value);
 402                                 TreeNode node = parent;
 403                                 while (node != null) {
 404                                         sb.Insert (0, tree.PathSeparator);
 405                                         sb.Insert (0, node.Value);
 406                                         node = node.Parent;
 407                                 }
 408                                 return sb.ToString ();
 409                         }
 410                 }
 411
 412                 internal int Index {
 413                         get { return index; }
 414                         set { index = value; ResetPathData (); }
 415                 }
 416
 417                 internal void SetParent (TreeNode node)
 418                 {
 419                         parent = node;
 420                         ResetPathData ();
 421                 }
 422
 423                 internal string Path {
 424                         get {
 425                                 if (path != null)
 426                                         return path;
 427                                 StringBuilder sb = new StringBuilder (index.ToString());
 428                                 TreeNode node = parent;
 429                                 while (node != null) {
 430                                         sb.Insert (0, '_');
 431                                         sb.Insert (0, node.Index.ToString ());
 432                                         node = node.Parent;
 433                                 }
 434                                 path = sb.ToString ();
 435                                 return path;
 436                         }
 437                 }
 438
 439                 internal bool Populated {
 440                         get {
 441                                 object o = ViewState ["Populated"];
 442                                 if (o != null)
 443                                         return (bool) o;
 444                                 return false;
 445                         }
 446                         set { ViewState ["Populated"] = value; }
 447                 }
 448
 449                 internal bool HasChildData {
 450                         get { return nodes != null; }
 451                 }
 452
 453                 internal void Populate ()
 454                 {
 455                         if (tree == null)
 456                                 return;
 457
 458                         populating = true;
 459                         tree.NotifyPopulateRequired (this);
 460                         populating = false;
 461                         Populated = true;
 462                 }
 463
 464                 public void Collapse ()
 465                 {
 466                         Expanded = false;
 467                 }
 468
 469                 public void CollapseAll ()
 470                 {
 471                         SetExpandedRec (false, -1);
 472                 }
 473
 474                 public void Expand ()
 475                 {
 476                         Expanded = true;
 477                 }
 478
 479                 internal void Expand (int depth)
 480                 {
 481                         SetExpandedRec (true, depth);
 482                 }
 483
 484                 public void ExpandAll ()
 485                 {
 486                         SetExpandedRec (true, -1);
 487                 }
 488
 489                 void SetExpandedRec (bool expanded, int depth)
 490                 {
 491                         Expanded = expanded;
 492                         if (depth == 0)
 493                                 return;
 494
 495                         foreach (TreeNode nod in ChildNodes)
 496                                 nod.SetExpandedRec (expanded, depth - 1);
 497                 }
 498
 499                 public void Select ()
 500                 {
 501                         Selected = true;
 502                 }
 503
 504                 public void ToggleExpandState ()
 505                 {
 506                         Expanded = !Expanded.GetValueOrDefault(false);
 507                 }
 508
 509                 void IStateManager.LoadViewState (object state)
 510                 {
 511                         LoadViewState (state);
 512                 }
 513
 514                 protected virtual void LoadViewState (object state)
 515                 {
 516                         if (state == null)
 517                                 return;
 518
 519                         object[] states = (object[]) state;
 520                         ViewState.LoadViewState (states [0]);
 521
 522                         if (tree != null && SelectedFlag)
 523                                 tree.SetSelectedNode (this, true);
 524
 525                         if (!PopulateOnDemand || Populated)
 526                                 ((IStateManager)ChildNodes).LoadViewState (states [1]);
 527                 }
 528
 529                 object IStateManager.SaveViewState ()
 530                 {
 531                         return SaveViewState ();
 532                 }
 533
 534                 protected virtual object SaveViewState ()
 535                 {
 536                         object[] states = new object[2];
 537                         states[0] = ViewState.SaveViewState();
 538                         states[1] = (nodes == null ? null : ((IStateManager)nodes).SaveViewState());
 539
 540                         for (int i = 0; i < states.Length; i++) {
 541                                 if (states [i] != null)
 542                                         return states;
 543                         }
 544                         return null;
 545                 }
 546
 547                 void IStateManager.TrackViewState ()
 548                 {
 549                         TrackViewState ();
 550                 }
 551
 552                 protected void TrackViewState ()
 553                 {
 554                         if (marked) return;
 555                         marked = true;
 556                         ViewState.TrackViewState();
 557
 558                         if (nodes != null)
 559                                 ((IStateManager)nodes).TrackViewState ();
 560                 }
 561
 562                 bool IStateManager.IsTrackingViewState {
 563                         get { return IsTrackingViewState; }
 564                 }
 565
 566                 protected bool IsTrackingViewState {
 567                         get { return marked; }
 568                 }
 569
 570                 internal void SetDirty ()
 571                 {
 572                         ViewState.SetDirty (true);
 573                         if (nodes != null)
 574                                 nodes.SetDirty ();
 575                 }
 576
 577                 public virtual object Clone ()
 578                 {
 579                         TreeNode nod = tree != null ? tree.CreateNode () : new TreeNode ();
 580                         foreach (DictionaryEntry e in ViewState)
 581                                 nod.ViewState [(string)e.Key] = ((StateItem)e.Value).Value;
 582
 583                         foreach (TreeNode c in ChildNodes)
 584                                 nod.ChildNodes.Add ((TreeNode)c.Clone ());
 585
 586                         return nod;
 587                 }
 588
 589                 object ICloneable.Clone ()
 590                 {
 591                         return Clone ();
 592                 }
 593
 594                 internal void Bind (IHierarchyData hierarchyData)
 595                 {
 596                         this.hierarchyData = hierarchyData;
 597                         DataBound = true;
 598                         DataPath = hierarchyData.Path;
 599                         dataItem = hierarchyData.Item;
 600
 601                         TreeNodeBinding bin = GetBinding ();
 602                         if (bin != null) {
 603
 604                                 // Bind ImageToolTip property
 605
 606                                 if (bin.ImageToolTipField.Length > 0) {
 607                                         ImageToolTip = Convert.ToString (GetBoundPropertyValue (bin.ImageToolTipField));
 608                                         if (ImageToolTip.Length == 0)
 609                                                 ImageToolTip = bin.ImageToolTip;
 610                                 } else if (bin.ImageToolTip.Length > 0)
 611                                         ImageToolTip = bin.ImageToolTip;
 612
 613                                 // Bind ImageUrl property
 614
 615                                 if (bin.ImageUrlField.Length > 0) {
 616                                         ImageUrl = Convert.ToString (GetBoundPropertyValue (bin.ImageUrlField));
 617                                         if (ImageUrl.Length == 0)
 618                                                 ImageUrl = bin.ImageUrl;
 619                                 } else if (bin.ImageUrl.Length > 0)
 620                                         ImageUrl = bin.ImageUrl;
 621
 622                                 // Bind NavigateUrl property
 623
 624                                 if (bin.NavigateUrlField.Length > 0) {
 625                                         NavigateUrl = Convert.ToString (GetBoundPropertyValue (bin.NavigateUrlField));
 626                                         if (NavigateUrl.Length == 0)
 627                                                 NavigateUrl = bin.NavigateUrl;
 628                                 } else if (bin.NavigateUrl.Length > 0)
 629                                         NavigateUrl = bin.NavigateUrl;
 630
 631                                 // Bind PopulateOnDemand property
 632
 633                                 if (bin.HasPropertyValue ("PopulateOnDemand"))
 634                                         PopulateOnDemand = bin.PopulateOnDemand;
 635
 636                                 // Bind SelectAction property
 637
 638                                 if (bin.HasPropertyValue ("SelectAction"))
 639                                         SelectAction = bin.SelectAction;
 640
 641                                 // Bind ShowCheckBox property
 642
 643                                 if (bin.HasPropertyValue ("ShowCheckBox"))
 644                                         ShowCheckBox = bin.ShowCheckBox;
 645
 646                                 // Bind Target property
 647
 648                                 if (bin.TargetField.Length > 0) {
 649                                         Target = Convert.ToString (GetBoundPropertyValue (bin.TargetField));
 650                                         if (Target.Length == 0)
 651                                                 Target = bin.Target;
 652                                 } else if (bin.Target.Length > 0)
 653                                         Target = bin.Target;
 654
 655                                 // Bind Text property
 656                                 string text = null;
 657                                 if (bin.TextField.Length > 0) {
 658                                         text = Convert.ToString (GetBoundPropertyValue (bin.TextField));
 659                                         if (bin.FormatString.Length > 0)
 660                                                 text = string.Format (bin.FormatString, text);
 661                                 }
 662                                 if (String.IsNullOrEmpty (text)) {
 663                                         if (bin.Text.Length > 0)
 664                                                 text = bin.Text;
 665                                         else if (bin.Value.Length > 0)
 666                                                 text = bin.Value;
 667                                 }
 668                                 if (!String.IsNullOrEmpty (text))
 669                                         Text = text;
 670
 671                                 // Bind ToolTip property
 672
 673                                 if (bin.ToolTipField.Length > 0) {
 674                                         ToolTip = Convert.ToString (GetBoundPropertyValue (bin.ToolTipField));
 675                                         if (ToolTip.Length == 0)
 676                                                 ToolTip = bin.ToolTip;
 677                                 } else if (bin.ToolTip.Length > 0)
 678                                         ToolTip = bin.ToolTip;
 679
 680                                 // Bind Value property
 681                                 string value = null;
 682                                 if (bin.ValueField.Length > 0) {
 683                                         value = Convert.ToString (GetBoundPropertyValue (bin.ValueField));
 684                                 }
 685                                 if (String.IsNullOrEmpty (value)) {
 686                                         if (bin.Value.Length > 0)
 687                                                 value = bin.Value;
 688                                         else if (bin.Text.Length > 0)
 689                                                 value = bin.Text;
 690                                 }
 691                                 if (!String.IsNullOrEmpty (value))
 692                                         Value = value;
 693                         } else {
 694                                 Text = Value = GetDefaultBoundText ();
 695                         }
 696
 697                         INavigateUIData navigateUIData = hierarchyData as INavigateUIData;
 698                         if (navigateUIData != null) {
 699                                 SelectAction = TreeNodeSelectAction.None;
 700                                 Text = navigateUIData.ToString ();
 701                                 NavigateUrl = navigateUIData.NavigateUrl;
 702                                 ToolTip = navigateUIData.Description;
 703                         }
 704                 }
 705
 706                 internal void SetDataItem (object item)
 707                 {
 708                         dataItem = item;
 709                 }
 710
 711                 internal void SetDataPath (string path)
 712                 {
 713                         DataPath = path;
 714                 }
 715
 716                 internal void SetDataBound (bool bound)
 717                 {
 718                         DataBound = bound;
 719                 }
 720
 721                 string GetDefaultBoundText ()
 722                 {
 723                         if (hierarchyData != null)
 724                                 return hierarchyData.ToString ();
 725                         else if (dataItem != null)
 726                                 return dataItem.ToString ();
 727                         else
 728                                 return string.Empty;
 729                 }
 730
 731                 string GetDataItemType ()
 732                 {
 733                         if (hierarchyData != null)
 734                                 return hierarchyData.Type;
 735                         else if (dataItem != null)
 736                                 return dataItem.GetType().ToString ();
 737                         else
 738                                 return string.Empty;
 739                 }
 740
 741                 internal bool IsParentNode {
 742                         get { return ChildNodes.Count > 0 || (PopulateOnDemand && !Populated); }
 743                 }
 744
 745                 internal bool IsLeafNode {
 746                         get { return !IsParentNode; }
 747                 }
 748
 749                 internal bool IsRootNode {
 750                         get { return Depth == 0; }
 751                 }
 752
 753                 TreeNodeBinding GetBinding ()
 754                 {
 755                         if (tree == null)
 756                                 return null;
 757                         if (gotBinding)
 758                                 return binding;
 759                         binding = tree.FindBindingForNode (GetDataItemType (), Depth);
 760                         gotBinding = true;
 761                         return binding;
 762                 }
 763
 764                 object GetBoundPropertyValue (string name)
 765                 {
 766                         if (boundProperties == null) {
 767                                 if (hierarchyData != null)
 768                                         boundProperties = TypeDescriptor.GetProperties (hierarchyData);
 769                                 else
 770                                         boundProperties = TypeDescriptor.GetProperties (dataItem);
 771                         }
 772
 773                         PropertyDescriptor prop = boundProperties.Find (name, true);
 774                         if (prop == null)
 775                                 throw new InvalidOperationException ("Property '" + name + "' not found in data bound item");
 776
 777                         if (hierarchyData != null)
 778                                 return prop.GetValue (hierarchyData);
 779                         else
 780                                 return prop.GetValue (dataItem);
 781                 }
 782
 783                 internal void BeginRenderText (HtmlTextWriter writer)
 784                 {
 785                         RenderPreText (writer);
 786                 }
 787
 788                 internal void EndRenderText (HtmlTextWriter writer)
 789                 {
 790                         RenderPostText (writer);
 791                 }
 792
 793                 protected virtual void RenderPreText (HtmlTextWriter writer)
 794                 {
 795                 }
 796
 797                 protected virtual void RenderPostText (HtmlTextWriter writer)
 798                 {
 799                 }
 800         }
 801 }