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

   1 //\r
   2 // System.Web.UI.Control.cs\r
   3 //\r
   4 // Author:\r
   5 //   Bob Smith <bob@thestuff.net>\r
   6 //\r
   7 // (C) Bob Smith\r
   8 //\r
   9 \r
  10 /*\r
  11  * Maintainer: bob@thestuff.net, gvaish@iitk.ac.in\r
  12  * (C) Bob Smith, Gaurav Vaish\r
  13  */\r
  14 \r
  15 //notes: view state only tracks changes after OnInit method is executed for the page request. You can read from it at any time, but cant write to it during rendering.\r
  16 //even more notes: view state info in trackviewstate method description. read later.\r
  17 //Ok, enough notes: what the heck is different between enable view state, and track view state.\r
  18 //Well, maybe not. How does the ViewState know when to track changes? Does it look at the property\r
  19 //on the owning control, or does it have a method/property of its own that gets called?\r
  20 // I think this last question is solved in the Interface for it. Look into this.\r
  21 \r
  22 //cycle:\r
  23 //init is called when control is first created.\r
  24 //load view state ic called right after init to populate the view state.\r
  25 //loadpostdata is called if ipostbackdatahandler is implemented.\r
  26 //load is called when control is loaded into a page\r
  27 //raisepostdatachangedevent if ipostbackdatahandler is implemented.\r
  28 //raisepostbackevent if ipostbackeventhandler is implemented.\r
  29 //prerender is called when the server is about to render its page object\r
  30 //SaveViewState is called.\r
  31 //Unload then dispose it apears. :)\r
  32 \r
  33 //Naming Container MUST have some methods. What are they? No clue. Help?\r
  34 \r
  35 //read this later. http://gotdotnet.com/quickstart/aspplus/\r
  36 //This to: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguidnf/html/cpconattributesdesign-timesupport.asp\r
  37 //http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguidnf/html/cpcontracefunctionality.asp\r
  38 \r
  39 // Isnt life grand? :)\r
  40 // See the undocumented methods? Gota love um. ;)\r
  41 // ASP.test4_aspx.Page_Load(Object Sender, EventArgs e) in \\genfs2\www24\bobsmith11\test4.aspx:6\r
  42 // System.Web.UI.Control.OnLoad(EventArgs e) +67\r
  43 // System.Web.UI.Control.LoadRecursive() +73\r
  44 // System.Web.UI.Page.ProcessRequestMain() +394\r
  45 \r
  46 // ASP.test4_aspx.Page_Unload(Object Sender, EventArgs e) in \\genfs2\www24\bobsmith11\test4.aspx:6\r
  47 // System.EventHandler.Invoke(Object sender, EventArgs e) +0\r
  48 // System.Web.UI.Control.OnUnload(EventArgs e) +67\r
  49 // System.Web.UI.Control.UnloadRecursive(Boolean dispose) +78\r
  50 // System.Web.UI.Page.ProcessRequest() +194\r
  51 // System.Web.UI.Page.ProcessRequest(HttpContext context) +18\r
  52 // System.Web.CallHandlerExecutionStep.Execute() +179\r
  53 // System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +87\r
  54 \r
  55 \r
  56 // ASP.test4_aspx.Page_Unload(Object Sender, EventArgs e) in \\genfs2\www24\bobsmith11\test4.aspx:6\r
  57 // System.Web.UI.Control.OnUnload(EventArgs e) +67\r
  58 // System.Web.UI.Control.UnloadRecursive(Boolean dispose) +78\r
  59 // System.Web.UI.Page.ProcessRequest()\r
  60 \r
  61 // ASP.test4_aspx.Page_Kill(Object Sender, EventArgs e) in \\genfs2\www24\bobsmith11\test4.aspx:6\r
  62 // System.Web.UI.Control.OnPreRender(EventArgs e) +67\r
  63 // System.Web.UI.Control.PreRenderRecursiveInternal() +61\r
  64 // System.Web.UI.Page.ProcessRequestMain() +753\r
  65 \r
  66 // ASP.test4_aspx.OnInit(EventArgs e) in \\genfs2\www24\bobsmith11\test4.aspx:6\r
  67 // System.Web.UI.Control.InitRecursive(Control namingContainer) +202\r
  68 // System.Web.UI.Page.ProcessRequestMain() +120\r
  69 \r
  70 // ASP.test4_aspx.SaveViewState() in \\genfs2\www24\bobsmith11\test4.aspx:12\r
  71 // System.Web.UI.Control.SaveViewStateRecursive() +51\r
  72 // System.Web.UI.Page.SavePageViewState() +174\r
  73 // System.Web.UI.Page.ProcessRequestMain() +861\r
  74 \r
  75 // ASP.test_aspx.LoadViewState(Object t) +28\r
  76 // System.Web.UI.Control.LoadViewStateRecursive(Object savedState) +125\r
  77 // System.Web.UI.Page.LoadPageViewState() +182\r
  78 // System.Web.UI.Page.ProcessRequestMain() +256\r
  79 \r
  80 using System;\r
  81 using System.Collections;\r
  82 using System.Web;\r
  83 using System.ComponentModel;\r
  84 \r
  85 namespace System.Web.UI\r
  86 {\r
  87         public class Control : IComponent, IDisposable, IParserAccessor, IDataBindingsAccessor\r
  88         {\r
  89                 private static readonly object DataBindingEvent = new object();\r
  90                 private static readonly object DisposedEvent = new object();\r
  91                 private static readonly object InitEvent = new object();\r
  92                 private static readonly object LoadEvent = new object();\r
  93                 private static readonly object PreRenderEvent = new object();\r
  94                 private static readonly object UnloadEvent = new object();\r
  95                 private string _userId = null;\r
  96                 private string _cachedUserId = null;\r
  97                 private string _cachedClientId = null;\r
  98                 private ControlCollection _controls = null;\r
  99                 private bool _enableViewState = true;\r
 100                 private IDictionary _childViewStates = null; //TODO: Not sure datatype. Placeholder guess.\r
 101                 private bool _isNamingContainer = false;\r
 102                 private Control _namingContainer = null;\r
 103                 private Page _page = null;\r
 104                 private Control _parent = null;\r
 105                 private ISite _site = null;\r
 106                 private bool _visible = true;\r
 107                 private HttpContext _context = null;\r
 108                 private bool _childControlsCreated = false;\r
 109                 private StateBag _viewState = null;\r
 110                 private bool _trackViewState = false;\r
 111                 private EventHandlerList _events = new EventHandlerList();\r
 112                 private RenderMethod _renderMethodDelegate = null;\r
 113                 \r
 114                     private DataBindingCollection dataBindings = null;\r
 115 \r
 116                 public Control()\r
 117                 {\r
 118                         if (this is INamingContainer) _isNamingContainer = true;\r
 119                 }\r
 120                 public virtual string ClientID //DIT\r
 121                 {\r
 122                         get\r
 123                         {\r
 124                                 if (_cachedUserId != null && _cachedClientId != null)\r
 125                                         return _cachedClientId;\r
 126                                 _cachedUserId = UniqueID.Replace(':', '_');\r
 127                                 return _cachedUserId;\r
 128                         }\r
 129                 }\r
 130                 public virtual ControlCollection Controls //DIT\r
 131                 {\r
 132                         get\r
 133                         {\r
 134                                 if (_controls == null) _controls = CreateControlCollection();\r
 135                                 return _controls;\r
 136                         }\r
 137                 }\r
 138                 public virtual bool EnableViewState //DIT\r
 139                 {\r
 140                         get\r
 141                         {\r
 142                                 return _enableViewState;\r
 143                         }\r
 144                         set\r
 145                         {\r
 146                                 _enableViewState = value;\r
 147                         }\r
 148                 }\r
 149                 public virtual string ID\r
 150                 {\r
 151                         get //DIT\r
 152                         {\r
 153                                 return _userId;\r
 154                         }\r
 155                         set\r
 156                         {\r
 157                                 if (value == null || value == "") return;\r
 158                                 _userId = value;\r
 159                                 _cachedUserId = null;\r
 160                                 //TODO: Some Naming Container stuff here I think.\r
 161                         }\r
 162                 }\r
 163                 public virtual Control NamingContainer //DIT\r
 164                 {\r
 165                         get\r
 166                         {\r
 167                                 if (_namingContainer == null && _parent != null)\r
 168                                 {\r
 169                                         if (_parent._isNamingContainer == false)\r
 170                                                 _namingContainer = _parent.NamingContainer;\r
 171                                         else\r
 172                                                 _namingContainer = _parent;\r
 173                                 }\r
 174                                 return _namingContainer;\r
 175                         }\r
 176                 }\r
 177                 public virtual Page Page //DIT\r
 178                 {\r
 179                         get\r
 180                         {\r
 181                                 if (_page == null && _parent != null) _page = _parent.Page;\r
 182                                 return _page;\r
 183                         }\r
 184                         set\r
 185                         {\r
 186                                 _page = value;\r
 187                         }\r
 188                 }\r
 189                 public virtual Control Parent //DIT\r
 190                 {\r
 191                         get\r
 192                         {\r
 193                                 return _parent;\r
 194                         }\r
 195                 }\r
 196                 public ISite Site //DIT\r
 197                 {\r
 198                         get\r
 199                         {\r
 200                                 return _site;\r
 201                         }\r
 202                         set\r
 203                         {\r
 204                                 _site = value;\r
 205                         }\r
 206                 }\r
 207                 public virtual string TemplateSourceDirectory\r
 208                 {\r
 209                         get\r
 210                         {\r
 211                                 return Context.Request.ApplicationPath; //TODO: Dont think this is right.\r
 212                         }\r
 213                 }\r
 214                 public virtual string UniqueID\r
 215                 {\r
 216                         get\r
 217                         {\r
 218                                 //TODO: Some Naming container methods here. What are they? Why arnt they declared?\r
 219                                 //Note: Nuked the old stuff here. Was total crap. :)\r
 220                                 throw new NotImplementedException();\r
 221                         }\r
 222                 }\r
 223                 public virtual bool Visible\r
 224                 { //TODO: Are children visible when parents are not?\r
 225                         get\r
 226                         {\r
 227                                 return _visible;\r
 228                         }\r
 229                         set\r
 230                         {\r
 231                                 _visible = value;\r
 232                         }\r
 233                 }\r
 234                 protected bool ChildControlsCreated //DIT\r
 235                 {\r
 236                         get\r
 237                         {\r
 238                                 return _childControlsCreated;\r
 239                         }\r
 240                         set\r
 241                         {\r
 242                                 if (value == false && _childControlsCreated == true)\r
 243                                         _controls.Clear();\r
 244                                 _childControlsCreated = value;\r
 245                         }\r
 246                 }\r
 247                 protected virtual HttpContext Context //DIT\r
 248                 {\r
 249                         get\r
 250                         {\r
 251                                 HttpContext context;\r
 252                                 if (_context != null)\r
 253                                         return _context;\r
 254                                 if (_parent == null)\r
 255                                         return HttpContext.Current;\r
 256                                 context = _parent.Context;\r
 257                                 if (context != null)\r
 258                                         return context;\r
 259                                 return HttpContext.Current;\r
 260                         }\r
 261                 }\r
 262                 protected EventHandlerList Events //DIT\r
 263                 {\r
 264                         get\r
 265                         {\r
 266                                 if (_events == null)\r
 267                                 {\r
 268                                         _events = new EventHandlerList();\r
 269                                 }\r
 270                                 return _events;\r
 271                         }\r
 272                 }\r
 273                 protected bool HasChildViewState //DIT\r
 274                 {\r
 275                         get\r
 276                         {\r
 277                                 if (_childViewStates == null) return false;\r
 278                                 return true;\r
 279                         }\r
 280                 }\r
 281                 protected bool IsTrackingViewState //DIT\r
 282                 {\r
 283                         get\r
 284                         {\r
 285                                 return _trackViewState;\r
 286                         }\r
 287                 }\r
 288                 protected virtual StateBag ViewState\r
 289                 {\r
 290                         get\r
 291                         {\r
 292                                 if(_viewState == null)\r
 293                                 {\r
 294                                         _viewState = new StateBag(ViewStateIgnoresCase);\r
 295                                 if(IsTrackingViewState)\r
 296                                                 _viewState.TrackViewState();\r
 297                                 }\r
 298                                 return _viewState;\r
 299                         }\r
 300                 }\r
 301                 protected virtual bool ViewStateIgnoresCase //DIT\r
 302                 {\r
 303                         get\r
 304                         {\r
 305                                 return true;\r
 306                         }\r
 307                 }\r
 308                 protected virtual void AddParsedSubObject(object obj) //DIT\r
 309                 {\r
 310                         Control c = (Control)obj;\r
 311                         if (c != null) Controls.Add(c);\r
 312                 }\r
 313                 protected void BuildProfileTree(string parentId, bool calcViewState)\r
 314                 {\r
 315                         //TODO\r
 316                 }\r
 317                 protected void ClearChildViewState()\r
 318                 {\r
 319                         //TODO\r
 320                         //Not quite sure about this. an example clears children then calls this, so I think\r
 321                         //view state is local to the current object, not children.\r
 322                 }\r
 323                 protected virtual void CreateChildControls() {} //DIT\r
 324                 protected virtual ControlCollection CreateControlCollection() //DIT\r
 325                 {\r
 326                         return new ControlCollection(this);\r
 327                 }\r
 328                 protected virtual void EnsureChildControls() //DIT\r
 329                 {\r
 330                         if (_childControlsCreated == false)\r
 331                         {\r
 332                                 CreateChildControls();\r
 333                                 ChildControlsCreated = true;\r
 334                         }\r
 335                 }\r
 336                 protected virtual Control FindControl(string id, int pathOffset)\r
 337                 {\r
 338                         //TODO: I think there is Naming Container stuff here. Redo.\r
 339                         int i;\r
 340                         for (i = pathOffset; i < _controls.Count; i++)\r
 341                                 if (_controls[i].ID == id) return _controls[i];\r
 342                         return null;\r
 343                 }\r
 344                 protected virtual void LoadViewState(object savedState)\r
 345                 {\r
 346                         //TODO: What should I do by default?\r
 347                 }\r
 348                 protected string MapPathSecure(string virtualPath)\r
 349                 {\r
 350                         throw new NotImplementedException();\r
 351                         //TODO: Need to read up on security+web.\r
 352                 }\r
 353                 protected virtual bool OnBubbleEvent(object source, EventArgs args) //DIT\r
 354                 {\r
 355                         return false;\r
 356                 }\r
 357                 protected virtual void OnDataBinding(EventArgs e) //DIT\r
 358                 {\r
 359                         if (_events != null)\r
 360                         {\r
 361                                 EventHandler eh = (EventHandler)(_events[DataBindingEvent]);\r
 362                                 if (eh != null) eh(this, e);\r
 363                         }\r
 364                 }\r
 365                 protected virtual void OnInit(EventArgs e) //DIT\r
 366                 {\r
 367                         if (_events != null)\r
 368                         {\r
 369                                 EventHandler eh = (EventHandler)(_events[InitEvent]);\r
 370                                 if (eh != null) eh(this, e);\r
 371                         }\r
 372                 }\r
 373                 protected virtual void OnLoad(EventArgs e) //DIT\r
 374                 {\r
 375                         if (_events != null)\r
 376                         {\r
 377                                 EventHandler eh = (EventHandler)(_events[LoadEvent]);\r
 378                                 if (eh != null) eh(this, e);\r
 379                         }\r
 380                 }\r
 381                 protected virtual void OnPreRender(EventArgs e) //DIT\r
 382                 {\r
 383                         if (_events != null)\r
 384                         {\r
 385                                 EventHandler eh = (EventHandler)(_events[PreRenderEvent]);\r
 386                                 if (eh != null) eh(this, e);\r
 387                         }\r
 388                 }\r
 389                 protected virtual void OnUnload(EventArgs e) //DIT\r
 390                 {\r
 391                         if (_events != null)\r
 392                         {\r
 393                                 EventHandler eh = (EventHandler)(_events[UnloadEvent]);\r
 394                                 if (eh != null) eh(this, e);\r
 395                         }\r
 396                 }\r
 397                 protected void RaiseBubbleEvent(object source, EventArgs args)\r
 398                 {\r
 399                         throw new NotImplementedException();\r
 400                         //return false;\r
 401                 }\r
 402                 protected virtual void Render(HtmlTextWriter writer) //DIT\r
 403                 {\r
 404                         RenderChildren(writer);\r
 405                 }\r
 406                 protected virtual void RenderChildren(HtmlTextWriter writer) //DIT\r
 407                 {\r
 408                         if (_renderMethodDelegate != null)\r
 409                                 _renderMethodDelegate(writer, this);\r
 410                         else if (_controls != null)\r
 411                                 foreach (Control c in _controls)\r
 412                                         c.RenderControl(writer);\r
 413                 }\r
 414                 protected virtual object SaveViewState()\r
 415                 {\r
 416                         return ViewState;\r
 417                 }\r
 418                 protected virtual void TrackViewState()\r
 419                 {\r
 420                         _trackViewState = true;\r
 421                 }\r
 422                 public virtual void Dispose()\r
 423                 {\r
 424                         //TODO: nuke stuff.\r
 425                         throw new NotImplementedException();\r
 426                         /*\r
 427                         if (_events != null)\r
 428                         {\r
 429                                 EventHandler eh = (EventHandler)(_events[DisposedEvent]);\r
 430                                 if (eh != null) eh(this, e);\r
 431                         }\r
 432                     */\r
 433                 }\r
 434                 public event EventHandler DataBinding //DIT\r
 435                 {\r
 436                         add\r
 437                         {\r
 438                                 Events.AddHandler(DataBindingEvent, value);\r
 439                         }\r
 440                         remove\r
 441                         {\r
 442                                 Events.RemoveHandler(DataBindingEvent, value);\r
 443                         }\r
 444                 }\r
 445                 public event EventHandler Disposed //DIT\r
 446                 {\r
 447                         add\r
 448                         {\r
 449                                 Events.AddHandler(DisposedEvent, value);\r
 450                         }\r
 451                         remove\r
 452                         {\r
 453                                 Events.RemoveHandler(DisposedEvent, value);\r
 454                         }\r
 455                 }\r
 456                 public event EventHandler Init //DIT\r
 457                 {\r
 458                         add\r
 459                         {\r
 460                                 Events.AddHandler(InitEvent, value);\r
 461                         }\r
 462                         remove\r
 463                         {\r
 464                                 Events.RemoveHandler(InitEvent, value);\r
 465                         }\r
 466                 }\r
 467                 public event EventHandler Load //DIT\r
 468                 {\r
 469                         add\r
 470                         {\r
 471                                 Events.AddHandler(LoadEvent, value);\r
 472                         }\r
 473                         remove\r
 474                         {\r
 475                                 Events.RemoveHandler(LoadEvent, value);\r
 476                         }\r
 477                 }\r
 478                 public event EventHandler PreRender //DIT\r
 479                 {\r
 480                         add\r
 481                         {\r
 482                                 Events.AddHandler(PreRenderEvent, value);\r
 483                         }\r
 484                         remove\r
 485                         {\r
 486                                 Events.RemoveHandler(PreRenderEvent, value);\r
 487                         }\r
 488                 }\r
 489                 public event EventHandler Unload //DIT\r
 490                 {\r
 491                         add\r
 492                         {\r
 493                                 Events.AddHandler(UnloadEvent, value);\r
 494                         }\r
 495                         remove\r
 496                         {\r
 497                                 Events.RemoveHandler(UnloadEvent, value);\r
 498                         }\r
 499                 }\r
 500                 public virtual void DataBind() //DIT\r
 501                 {\r
 502                         OnDataBinding(EventArgs.Empty);\r
 503                         if (_controls != null)\r
 504                                 foreach (Control c in _controls)\r
 505                                         c.DataBind();\r
 506                 }\r
 507                 public virtual Control FindControl(string id) //DIT\r
 508                 {\r
 509                         return FindControl(id, 0);\r
 510                 }\r
 511                 public virtual bool HasControls() //DIT\r
 512                 {\r
 513                         if (_controls != null && _controls.Count >0) return true;\r
 514                         return false;\r
 515                 }\r
 516                 public void RenderControl(HtmlTextWriter writer)\r
 517                 {\r
 518                         if (_visible)\r
 519                         {\r
 520                                 //TODO: Something about tracing here.\r
 521                                 Render(writer);\r
 522                         }\r
 523                 }\r
 524                 public string ResolveUrl(string relativeUrl)\r
 525                 {\r
 526                         throw new NotImplementedException();\r
 527                 }\r
 528                 public void SetRenderMethodDelegate(RenderMethod renderMethod) //DIT\r
 529                 {\r
 530                         _renderMethodDelegate = renderMethod;\r
 531                 }\r
 532                 protected void LoadRecursive()\r
 533                 {\r
 534                         OnLoad(EventArgs.Empty);\r
 535                         if (_controls != null) foreach (Control c in _controls) c.LoadRecursive();\r
 536                 }\r
 537                 protected void UnloadRecursive(Boolean dispose)\r
 538                 {\r
 539                         OnUnload(EventArgs.Empty);\r
 540                         if (_controls != null) foreach (Control c in _controls) c.UnloadRecursive(dispose);\r
 541                         if (dispose) Dispose();\r
 542                 }\r
 543                 protected void PreRenderRecursiveInternal()\r
 544                 {\r
 545                         OnPreRender(EventArgs.Empty);\r
 546                         if (_controls != null) foreach (Control c in _controls) c.PreRenderRecursiveInternal();\r
 547                 }\r
 548                 protected void InitRecursive(Control namingContainer)\r
 549                 {\r
 550                         if (_controls != null) foreach (Control c in _controls) c.InitRecursive(namingContainer);\r
 551                         OnInit(EventArgs.Empty);\r
 552                 }\r
 553                 protected object SaveViewStateRecursive()\r
 554                 {\r
 555                         throw new NotImplementedException();\r
 556                 }\r
 557                 protected void LoadViewStateRecursive(Object savedState)\r
 558                 {\r
 559                         throw new NotImplementedException();\r
 560                 }\r
 561                 \r
 562                 void IParserAccessor.AddParsedSubObject(object obj)\r
 563                 {\r
 564                         this.AddParsedSubObject(obj);\r
 565                 }\r
 566                 \r
 567                 DataBindingCollection IDataBindingsAccessor.DataBindings\r
 568                 {\r
 569                         get\r
 570                         {\r
 571                                 if(dataBindings == null)\r
 572                                         dataBindings = new DataBindingCollection();\r
 573                                 return dataBindings;\r
 574                         }\r
 575                 }\r
 576                 \r
 577                 bool IDataBindingsAccessor.HasDataBindings\r
 578                 {\r
 579                         get\r
 580                         {\r
 581                                 return (dataBindings!=null && dataBindings.Count>0);\r
 582                         }\r
 583                 }\r
 584                 \r
 585                 //TODO: I think there are some needed Interface implementations to do here.\r
 586                 //TODO: Find api for INamingContainer.\r
 587         }\r
 588 }\r