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

   1 //
   2 // System.Web.UI.WebControls.Image.cs
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // Copyright (C) 2005 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
  29 using System.ComponentModel;
  30 using System.Security.Permissions;
  31
  32 namespace System.Web.UI.WebControls {
  33
  34         // Note: this control can live inside or outside a <form> element
  35
  36         // CAS
  37         [AspNetHostingPermissionAttribute (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  38         [AspNetHostingPermissionAttribute (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  39         // attributes
  40         [DefaultProperty ("ImageUrl")]
  41 #if NET_2_0
  42         [Designer ("System.Web.UI.Design.WebControls.PreviewControlDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
  43 #endif
  44         public class Image : WebControl {
  45
  46                 public Image ()
  47                         : base (HtmlTextWriterTag.Img)
  48                 {
  49                 }
  50
  51
  52                 [Bindable (true)]
  53                 [DefaultValue ("")]
  54 #if NET_2_0
  55                 [Localizable (true)]
  56 #endif
  57                 [WebSysDescription ("")]
  58                 [WebCategory ("Appearance")]
  59                 public virtual string AlternateText {
  60                         get {
  61                                 string s = (string) ViewState ["AlternateText"];
  62                                 return (s == null) ? String.Empty : s;
  63                         }
  64                         set {
  65                                 if (value == null)
  66                                         ViewState.Remove ("AlternateText");
  67                                 else
  68                                         ViewState ["AlternateText"] = value;
  69                         }
  70                 }
  71
  72                 // not applicable to Image
  73                 [Browsable (false)]
  74                 [EditorBrowsable (EditorBrowsableState.Never)]
  75                 public override bool Enabled {
  76                         get { return base.Enabled; }
  77                         set {base.Enabled = value; }
  78                 }
  79
  80                 // not applicable to Image
  81                 [Browsable (false)]
  82                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
  83                 [EditorBrowsable (EditorBrowsableState.Never)]
  84                 public override FontInfo Font {
  85                         get { return base.Font; }
  86                 }
  87
  88 #if ONLY_1_1
  89                 [Bindable (true)]
  90 #endif
  91                 [DefaultValue (ImageAlign.NotSet)]
  92                 [WebSysDescription ("")]
  93                 [WebCategory ("Layout")]
  94                 public virtual ImageAlign ImageAlign {
  95                         get {
  96                                 object o = ViewState ["ImageAlign"];
  97                                 return (o == null) ? ImageAlign.NotSet : (ImageAlign) o;
  98                         }
  99                         set {
 100                                 // avoid reflection
 101                                 if ((value < ImageAlign.NotSet) || (value > ImageAlign.TextTop)) {
 102                                         // invalid ImageAlign (note: 2.0 beta2 documents ArgumentException)
 103                                         throw new ArgumentOutOfRangeException (Locale.GetText ("Invalid ImageAlign value."));
 104                                 }
 105                                 ViewState ["ImageAlign"] = value;
 106                         }
 107                 }
 108
 109                 [Bindable (true)]
 110                 [DefaultValue ("")]
 111 #if NET_2_0
 112                 [Editor ("System.Web.UI.Design.ImageUrlEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 113                 [UrlProperty]
 114 #else
 115                 [Editor ("System.Web.UI.Design.ImageUrlEditor, " + Consts.AssemblySystem_Design, typeof (System.Drawing.Design.UITypeEditor))]
 116 #endif
 117                 [WebSysDescription ("")]
 118                 [WebCategory ("Appearance")]
 119                 public virtual string ImageUrl {
 120                         get {
 121                                 string s = (string) ViewState ["ImageUrl"];
 122                                 return (s == null) ? String.Empty : s;
 123                         }
 124                         set {
 125                                 if (value == null)
 126                                         ViewState.Remove ("ImageUrl");
 127                                 else
 128                                         ViewState ["ImageUrl"] = value;
 129                         }
 130                 }
 131
 132                 // this was added in Fx 1.1 SP1
 133                 [DefaultValue ("")]
 134 #if NET_2_0
 135                 [Editor ("System.Web.UI.Design.UrlEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 136                 [UrlProperty]
 137 #endif
 138                 [WebSysDescription ("")]
 139                 [WebCategory ("Accessibility")]
 140                 public virtual string DescriptionUrl {
 141                         get {
 142                                 string s = (string) ViewState ["DescriptionUrl"];
 143                                 return (s == null) ? String.Empty : s;
 144                         }
 145                         set {
 146                                 if (value == null)
 147                                         ViewState.Remove ("DescriptionUrl");
 148                                 else
 149                                         ViewState ["DescriptionUrl"] = value;
 150                         }
 151                 }
 152
 153 #if NET_2_0
 154                 [DefaultValue (false)]
 155                 [WebSysDescription ("")]
 156                 [WebCategory ("Accessibility")]
 157                 public virtual bool GenerateEmptyAlternateText {
 158                         get {
 159                                 object o = ViewState ["GenerateEmptyAlternateText"];
 160                                 return (o == null) ? false : (bool) o;
 161                         }
 162                         set {
 163                                 ViewState ["GenerateEmptyAlternateText"] = value;
 164                         }
 165                 }
 166 #endif
 167
 168
 169                 protected override void AddAttributesToRender (HtmlTextWriter writer)
 170                 {
 171                         base.AddAttributesToRender (writer);
 172 #if NET_2_0
 173                         // src is always present, even if empty, in 2.0
 174                         writer.AddAttribute (HtmlTextWriterAttribute.Src, ResolveClientUrl (ImageUrl));
 175                         string s = AlternateText;
 176                         if ((s.Length > 0) || GenerateEmptyAlternateText)
 177                                 writer.AddAttribute (HtmlTextWriterAttribute.Alt, s);
 178                         s = DescriptionUrl;
 179                         if (s.Length > 0)
 180                                 writer.AddAttribute (HtmlTextWriterAttribute.Longdesc, ResolveClientUrl (s));
 181 #else
 182                         string s = ImageUrl;
 183                         if (s.Length > 0)
 184                                 writer.AddAttribute (HtmlTextWriterAttribute.Src, ResolveClientUrl (s));
 185                         // alt is always present, even if empty, in 1.x
 186                         writer.AddAttribute (HtmlTextWriterAttribute.Alt, AlternateText);
 187                         // added in Fx 1.1 SP1 but the HtmlTextWriterAttribute wasn't
 188                         s = DescriptionUrl;
 189                         if (s.Length > 0)
 190                                 writer.AddAttribute ("longdesc", s);
 191 #endif
 192                         switch (ImageAlign) {
 193                         case ImageAlign.Left:
 194                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "left", false);
 195                                 break;
 196                         case ImageAlign.Right:
 197                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "right", false);
 198                                 break;
 199                         case ImageAlign.Baseline:
 200                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "baseline", false);
 201                                 break;
 202                         case ImageAlign.Top:
 203                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "top", false);
 204                                 break;
 205                         case ImageAlign.Middle:
 206                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "middle", false);
 207                                 break;
 208                         case ImageAlign.Bottom:
 209                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "bottom", false);
 210                                 break;
 211                         case ImageAlign.AbsBottom:
 212                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "absbottom", false);
 213                                 break;
 214                         case ImageAlign.AbsMiddle:
 215                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "absmiddle", false);
 216                                 break;
 217                         case ImageAlign.TextTop:
 218                                 writer.AddAttribute (HtmlTextWriterAttribute.Align, "texttop", false);
 219                                 break;
 220                         }
 221 #if NET_2_0
 222 #if BUG_78875_FIXED
 223                         if (Context.Request.Browser.SupportsCss)
 224 #endif
 225                         if (BorderWidth.IsEmpty)
 226                                 writer.AddStyleAttribute (HtmlTextWriterStyle.BorderWidth, "0px");
 227 #if BUG_78875_FIXED
 228                         else
 229 #endif
 230 #else
 231                         // if border-with is not specified in style or
 232                         // no style is defined - set image to no border
 233                         if (!ControlStyleCreated || ControlStyle.BorderWidth.IsEmpty)
 234                                 writer.AddAttribute (HtmlTextWriterAttribute.Border, "0");
 235 #endif
 236                 }
 237
 238 #if NET_2_0
 239                 protected internal
 240 #else
 241                 protected
 242 #endif
 243                 override void RenderContents (HtmlTextWriter writer)
 244                 {
 245                         base.RenderContents (writer);
 246                 }
 247         }
 248 }