mcs/class/System.Web.Mvc2/System.Web.Mvc/ViewUserControl.cs

   1 /* ****************************************************************************\r
   2  *\r
   3  * Copyright (c) Microsoft Corporation. All rights reserved.\r
   4  *\r
   5  * This software is subject to the Microsoft Public License (Ms-PL). \r
   6  * A copy of the license can be found in the license.htm file included \r
   7  * in this distribution.\r
   8  *\r
   9  * You must not remove this notice, or any other, from this software.\r
  10  *\r
  11  * ***************************************************************************/\r
  12 \r
  13 namespace System.Web.Mvc {\r
  14     using System;\r
  15     using System.ComponentModel;\r
  16     using System.Diagnostics.CodeAnalysis;\r
  17     using System.Globalization;\r
  18     using System.IO;\r
  19     using System.Web.Mvc.Resources;\r
  20     using System.Web.UI;\r
  21 \r
  22     [FileLevelControlBuilder(typeof(ViewUserControlControlBuilder))]\r
  23     public class ViewUserControl : UserControl, IViewDataContainer {\r
  24         private AjaxHelper<object> _ajaxHelper;\r
  25         private HtmlHelper<object> _htmlHelper;\r
  26         private ViewContext _viewContext;\r
  27         private ViewDataDictionary _viewData;\r
  28         private string _viewDataKey;\r
  29 \r
  30         public AjaxHelper<object> Ajax {\r
  31             get {\r
  32                 if (_ajaxHelper == null) {\r
  33                     _ajaxHelper = new AjaxHelper<object>(ViewContext, this);\r
  34                 }\r
  35                 return _ajaxHelper;\r
  36             }\r
  37         }\r
  38 \r
  39         public HtmlHelper<object> Html {\r
  40             get {\r
  41                 if (_htmlHelper == null) {\r
  42                     _htmlHelper = new HtmlHelper<object>(ViewContext, this);\r
  43                 }\r
  44                 return _htmlHelper;\r
  45             }\r
  46         }\r
  47 \r
  48         public object Model {\r
  49             get {\r
  50                 return ViewData.Model;\r
  51             }\r
  52         }\r
  53 \r
  54         public TempDataDictionary TempData {\r
  55             get {\r
  56                 return ViewPage.TempData;\r
  57             }\r
  58         }\r
  59 \r
  60         public UrlHelper Url {\r
  61             get {\r
  62                 return ViewPage.Url;\r
  63             }\r
  64         }\r
  65 \r
  66         [Browsable(false)]\r
  67         [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]\r
  68         public ViewContext ViewContext {\r
  69             get {\r
  70                 return _viewContext ?? ViewPage.ViewContext;\r
  71             }\r
  72             set {\r
  73                 _viewContext = value;\r
  74             }\r
  75         }\r
  76 \r
  77         [SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly",\r
  78             Justification = "This is the mechanism by which the ViewUserControl gets its ViewDataDictionary object.")]\r
  79         [Browsable(false)]\r
  80         [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]\r
  81         public ViewDataDictionary ViewData {\r
  82             get {\r
  83                 EnsureViewData();\r
  84                 return _viewData;\r
  85             }\r
  86             set {\r
  87                 SetViewData(value);\r
  88             }\r
  89         }\r
  90 \r
  91         [DefaultValue("")]\r
  92         public string ViewDataKey {\r
  93             get {\r
  94                 return _viewDataKey ?? String.Empty;\r
  95             }\r
  96             set {\r
  97                 _viewDataKey = value;\r
  98             }\r
  99         }\r
 100 \r
 101         internal ViewPage ViewPage {\r
 102             get {\r
 103                 ViewPage viewPage = Page as ViewPage;\r
 104                 if (viewPage == null) {\r
 105                     throw new InvalidOperationException(MvcResources.ViewUserControl_RequiresViewPage);\r
 106                 }\r
 107                 return viewPage;\r
 108             }\r
 109         }\r
 110 \r
 111         public HtmlTextWriter Writer {\r
 112             get {\r
 113                 return ViewPage.Writer;\r
 114             }\r
 115         }\r
 116 \r
 117         protected virtual void SetViewData(ViewDataDictionary viewData) {\r
 118             _viewData = viewData;\r
 119         }\r
 120 \r
 121         protected void EnsureViewData() {\r
 122             if (_viewData != null) {\r
 123                 return;\r
 124             }\r
 125 \r
 126             // Get the ViewData for this ViewUserControl, optionally using the specified ViewDataKey\r
 127             IViewDataContainer vdc = GetViewDataContainer(this);\r
 128             if (vdc == null) {\r
 129                 throw new InvalidOperationException(\r
 130                     String.Format(\r
 131                         CultureInfo.CurrentUICulture,\r
 132                         MvcResources.ViewUserControl_RequiresViewDataProvider,\r
 133                         AppRelativeVirtualPath));\r
 134             }\r
 135 \r
 136             ViewDataDictionary myViewData = vdc.ViewData;\r
 137 \r
 138             // If we have a ViewDataKey, try to extract the ViewData from the dictionary, otherwise\r
 139             // return the container's ViewData.\r
 140             if (!String.IsNullOrEmpty(ViewDataKey)) {\r
 141                 object target = myViewData.Eval(ViewDataKey);\r
 142                 myViewData = target as ViewDataDictionary ?? new ViewDataDictionary(myViewData) { Model = target };\r
 143             }\r
 144 \r
 145             SetViewData(myViewData);\r
 146         }\r
 147 \r
 148         private static IViewDataContainer GetViewDataContainer(Control control) {\r
 149             // Walk up the control hierarchy until we find someone that implements IViewDataContainer\r
 150             while (control != null) {\r
 151                 control = control.Parent;\r
 152                 IViewDataContainer vdc = control as IViewDataContainer;\r
 153                 if (vdc != null) {\r
 154                     return vdc;\r
 155                 }\r
 156             }\r
 157             return null;\r
 158         }\r
 159 \r
 160         public virtual void RenderView(ViewContext viewContext) {\r
 161             ViewUserControlContainerPage containerPage = new ViewUserControlContainerPage(this);\r
 162 \r
 163             RenderViewAndRestoreContentType(containerPage, viewContext);\r
 164         }\r
 165 \r
 166         internal static void RenderViewAndRestoreContentType(ViewPage containerPage, ViewContext viewContext) {\r
 167             // We need to restore the Content-Type since Page.SetIntrinsics() will reset it. It's not possible\r
 168             // to work around the call to SetIntrinsics() since the control's render method requires the\r
 169             // containing page's Response property to be non-null, and SetIntrinsics() is the only way to set\r
 170             // this.\r
 171             string savedContentType = viewContext.HttpContext.Response.ContentType;\r
 172             containerPage.RenderView(viewContext);\r
 173             viewContext.HttpContext.Response.ContentType = savedContentType;\r
 174         }\r
 175 \r
 176         [SuppressMessage("Microsoft.Usage", "CA1801:ReviewUnusedParameters", MessageId = "textWriter",\r
 177             Justification = "This method existed in MVC 1.0 and has been deprecated.")]\r
 178         [SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic",\r
 179             Justification = "This method existed in MVC 1.0 and has been deprecated.")]\r
 180         [Obsolete("The TextWriter is now provided by the ViewContext object passed to the RenderView method.", true /* error */)]\r
 181         public void SetTextWriter(TextWriter textWriter) {\r
 182             // this is now a no-op\r
 183         }\r
 184 \r
 185         private sealed class ViewUserControlContainerPage : ViewPage {\r
 186             private readonly ViewUserControl _userControl;\r
 187 \r
 188             public ViewUserControlContainerPage(ViewUserControl userControl) {\r
 189                 _userControl = userControl;\r
 190             }\r
 191 \r
 192             public override void ProcessRequest(HttpContext context) {\r
 193                 _userControl.ID = ViewPage.NextId();\r
 194                 Controls.Add(_userControl);\r
 195 \r
 196                 base.ProcessRequest(context);\r
 197             }\r
 198         }\r
 199     }\r
 200 }\r