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

   1 //
   2 // System.Web.UI.WebControls.ImageField.cs
   3 //
   4 // Authors:
   5 //      Lluis Sanchez Gual (lluis@novell.com)
   6 //
   7 // (C) 2005-2010 Novell, Inc (http://www.novell.com)
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System.Collections;
  32 using System.Collections.Specialized;
  33 using System.Web.UI;
  34 using System.ComponentModel;
  35 using System.Security.Permissions;
  36 using System.Reflection;
  37
  38 namespace System.Web.UI.WebControls {
  39
  40         [AspNetHostingPermissionAttribute (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  41         [AspNetHostingPermissionAttribute (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  42         public class ImageField : DataControlField
  43         {
  44                 public static readonly string ThisExpression = "!";
  45
  46                 PropertyDescriptor imageProperty;
  47                 PropertyDescriptor textProperty;
  48
  49                 public override bool Initialize (bool sortingEnabled, Control control)
  50                 {
  51                         return base.Initialize (sortingEnabled, control);
  52                 }
  53
  54                 [DefaultValueAttribute ("")]
  55                 [LocalizableAttribute (true)]
  56                 [WebSysDescription ("")]
  57                 [WebCategoryAttribute ("Appearance")]
  58                 public virtual string AlternateText {
  59                         get {
  60                                 object ob = ViewState ["AlternateText"];
  61                                 if (ob != null)
  62                                         return (string) ob;
  63                                 return String.Empty;
  64                         }
  65                         set {
  66                                 ViewState ["AlternateText"] = value;
  67                                 OnFieldChanged ();
  68                         }
  69                 }
  70
  71                 [DefaultValueAttribute (true)]
  72                 [WebSysDescription ("")]
  73                 [WebCategoryAttribute ("Behavior")]
  74                 public virtual bool ConvertEmptyStringToNull {
  75                         get {
  76                                 object ob = ViewState ["ConvertEmptyStringToNull"];
  77                                 if (ob != null)
  78                                         return (bool) ob;
  79                                 return true;
  80                         }
  81                         set {
  82                                 ViewState ["ConvertEmptyStringToNull"] = value;
  83                                 OnFieldChanged ();
  84                         }
  85                 }
  86
  87                 [TypeConverterAttribute ("System.Web.UI.Design.DataSourceViewSchemaConverter, " + Consts.AssemblySystem_Design)]
  88                 [DefaultValueAttribute ("")]
  89                 [WebSysDescription ("")]
  90                 [WebCategoryAttribute ("Data")]
  91                 public virtual string DataAlternateTextField {
  92                         get {
  93                                 object ob = ViewState ["DataAlternateTextField"];
  94                                 if (ob != null)
  95                                         return (string) ob;
  96                                 return String.Empty;
  97                         }
  98                         set {
  99                                 ViewState ["DataAlternateTextField"] = value;
 100                                 OnFieldChanged ();
 101                         }
 102                 }
 103
 104                 [DefaultValueAttribute ("")]
 105                 [WebSysDescription ("")]
 106                 [WebCategoryAttribute ("Data")]
 107                 public virtual string DataAlternateTextFormatString {
 108                         get {
 109                                 object ob = ViewState ["DataAlternateTextFormatString"];
 110                                 if (ob != null)
 111                                         return (string) ob;
 112                                 return String.Empty;
 113                         }
 114                         set {
 115                                 ViewState ["DataAlternateTextFormatString"] = value;
 116                                 OnFieldChanged ();
 117                         }
 118                 }
 119
 120                 [TypeConverterAttribute ("System.Web.UI.Design.DataSourceViewSchemaConverter, " + Consts.AssemblySystem_Design)]
 121                 [DefaultValueAttribute ("")]
 122                 [WebSysDescription ("")]
 123                 [WebCategoryAttribute ("Data")]
 124                 public virtual string DataImageUrlField {
 125                         get {
 126                                 object ob = ViewState ["DataImageUrlField"];
 127                                 if (ob != null)
 128                                         return (string) ob;
 129                                 return String.Empty;
 130                         }
 131                         set {
 132                                 ViewState ["DataImageUrlField"] = value;
 133                                 OnFieldChanged ();
 134                         }
 135                 }
 136
 137                 [DefaultValueAttribute ("")]
 138                 [WebSysDescription ("")]
 139                 [WebCategoryAttribute ("Data")]
 140                 public virtual string DataImageUrlFormatString {
 141                         get {
 142                                 object ob = ViewState ["DataImageUrlFormatString"];
 143                                 if (ob != null)
 144                                         return (string) ob;
 145                                 return String.Empty;
 146                         }
 147                         set {
 148                                 ViewState ["DataImageUrlFormatString"] = value;
 149                                 OnFieldChanged ();
 150                         }
 151                 }
 152
 153                 [DefaultValueAttribute ("")]
 154                 [LocalizableAttribute (true)]
 155                 [WebSysDescription ("")]
 156                 [WebCategoryAttribute ("Behavior")]
 157                 public virtual string NullDisplayText {
 158                         get {
 159                                 object ob = ViewState ["NullDisplayText"];
 160                                 if (ob != null) return (string) ob;
 161                                 return "";
 162                         }
 163                         set {
 164                                 ViewState ["NullDisplayText"] = value;
 165                                 OnFieldChanged ();
 166                         }
 167                 }
 168
 169                 [DefaultValueAttribute ("")]
 170                 [EditorAttribute ("System.Web.UI.Design.ImageUrlEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 171                 [UrlPropertyAttribute]
 172                 [WebSysDescription ("")]
 173                 [WebCategoryAttribute ("Behavior")]
 174                 public virtual string NullImageUrl {
 175                         get {
 176                                 object ob = ViewState ["NullImageUrl"];
 177                                 if (ob != null)
 178                                         return (string) ob;
 179                                 return String.Empty;
 180                         }
 181                         set {
 182                                 ViewState ["NullImageUrl"] = value;
 183                                 OnFieldChanged ();
 184                         }
 185                 }
 186
 187                 [DefaultValueAttribute (false)]
 188                 [WebSysDescription ("")]
 189                 [WebCategoryAttribute ("Behavior")]
 190                 public virtual bool ReadOnly {
 191                         get {
 192                                 object val = ViewState ["ReadOnly"];
 193                                 return val != null ? (bool) val : false;
 194                         }
 195                         set {
 196                                 ViewState ["ReadOnly"] = value;
 197                                 OnFieldChanged ();
 198                         }
 199                 }
 200
 201                 public override void ExtractValuesFromCell (IOrderedDictionary dictionary, DataControlFieldCell cell, DataControlRowState rowState, bool includeReadOnly)
 202                 {
 203                         if ((ReadOnly && !includeReadOnly) || cell.Controls.Count == 0)
 204                                 return;
 205
 206                         bool editable = (rowState & (DataControlRowState.Edit | DataControlRowState.Insert)) != 0;
 207                         if (includeReadOnly || editable) {
 208                                 Control control = cell.Controls [0];
 209                                 //TODO: other controls?
 210                                 if (control is Image)
 211                                         dictionary [DataImageUrlField] = ((Image)control).ImageUrl;
 212                                 else if (control is TextBox)
 213                                         dictionary [DataImageUrlField] = ((TextBox) control).Text;
 214                         }
 215                 }
 216
 217                 public override void InitializeCell (DataControlFieldCell cell, DataControlCellType cellType, DataControlRowState rowState, int rowIndex)
 218                 {
 219                         base.InitializeCell (cell, cellType, rowState, rowIndex);
 220                         if (cellType == DataControlCellType.DataCell) {
 221                                 InitializeDataCell (cell, rowState);
 222                                 if ((rowState & DataControlRowState.Insert) == 0)
 223                                         cell.DataBinding += new EventHandler (OnDataBindField);
 224                         }
 225                 }
 226
 227                 protected virtual void InitializeDataCell (DataControlFieldCell cell, DataControlRowState rowState)
 228                 {
 229                         bool editable = (rowState & (DataControlRowState.Edit | DataControlRowState.Insert)) != 0;
 230                         if (editable && !ReadOnly) {
 231                                 TextBox box = new TextBox ();
 232                                 cell.Controls.Add (box);
 233                         } else if (DataImageUrlField.Length > 0) {
 234                                 Image img = new Image ();
 235                                 img.ControlStyle.CopyFrom (ControlStyle);
 236                                 cell.Controls.Add (img);
 237                         }
 238                 }
 239
 240                 protected virtual string FormatImageUrlValue (object value)
 241                 {
 242                         if (value == null)
 243                                 return null;
 244                         else if (DataImageUrlFormatString.Length > 0)
 245                                 return string.Format (DataImageUrlFormatString, value);
 246                         else
 247                                 return value.ToString ();
 248                 }
 249
 250                 protected virtual string GetFormattedAlternateText (Control controlContainer)
 251                 {
 252                         if (DataAlternateTextField.Length > 0) {
 253                                 if (textProperty == null)
 254                                         textProperty = GetProperty (controlContainer, DataAlternateTextField);
 255
 256                                 object value = GetValue (controlContainer, DataAlternateTextField, ref textProperty);
 257
 258                                 if (value == null || (value.ToString().Length == 0 && ConvertEmptyStringToNull))
 259                                         return NullDisplayText;
 260                                 else if (DataAlternateTextFormatString.Length > 0)
 261                                         return string.Format (DataAlternateTextFormatString, value);
 262                                 else
 263                                         return value.ToString ();
 264                         } else
 265                                 return AlternateText;
 266
 267                 }
 268
 269                 protected virtual object GetValue (Control controlContainer, string fieldName, ref PropertyDescriptor cachedDescriptor)
 270                 {
 271                         if (DesignMode)
 272                                 return GetDesignTimeValue ();
 273                         else {
 274                                 object dataItem = DataBinder.GetDataItem (controlContainer);
 275                                 if (dataItem == null)
 276                                         throw new HttpException ("A data item was not found in the container. The container must either implement IDataItemContainer, or have a property named DataItem.");
 277                                 if (fieldName == ThisExpression)
 278                                         return dataItem;
 279                                 else {
 280                                         if (cachedDescriptor != null) return cachedDescriptor.GetValue (dataItem);
 281                                         PropertyDescriptor prop = GetProperty (controlContainer, fieldName);
 282                                         return prop.GetValue (dataItem);
 283                                 }
 284                         }
 285                 }
 286
 287                 PropertyDescriptor GetProperty (Control controlContainer, string fieldName)
 288                 {
 289                         if (fieldName == ThisExpression)
 290                                 return null;
 291
 292                         IDataItemContainer dic = (IDataItemContainer) controlContainer;
 293                         PropertyDescriptorCollection properties = TypeDescriptor.GetProperties (dic.DataItem);
 294                         PropertyDescriptor prop = properties != null ? properties [fieldName] : null;
 295                         if (prop == null)
 296                                 throw new InvalidOperationException ("Property '" + fieldName + "' not found in object of type " + dic.DataItem.GetType());
 297
 298                         return prop;
 299                 }
 300
 301                 protected virtual string GetDesignTimeValue ()
 302                 {
 303                         return "Databound";
 304                 }
 305
 306                 protected virtual void OnDataBindField (object sender, EventArgs e)
 307                 {
 308                         Control control = (Control) sender;
 309                         ControlCollection controls = control != null ? control.Controls : null;
 310                         Control namingContainer = control.NamingContainer;
 311                         Control c;
 312                         if (sender is DataControlFieldCell) {
 313                                 if (controls.Count == 0)
 314                                         return;
 315                                 c = controls [0];
 316                         } else if (sender is Image || sender is TextBox)
 317                                 c = control;
 318                         else
 319                                 return;
 320
 321                         if (imageProperty == null)
 322                                 imageProperty = GetProperty (namingContainer, DataImageUrlField);
 323
 324                         if (c is TextBox) {
 325                                 object val = GetValue (namingContainer, DataImageUrlField, ref imageProperty);
 326                                 ((TextBox)c).Text = val != null ? val.ToString() : String.Empty;
 327                         } else if (c is Image) {
 328                                 Image img = (Image)c;
 329                                 string value =  FormatImageUrlValue (GetValue (namingContainer, DataImageUrlField, ref imageProperty));
 330                                 if (value == null || (ConvertEmptyStringToNull && value.Length == 0)) {
 331                                         if (NullImageUrl == null || NullImageUrl.Length == 0) {
 332                                                 c.Visible = false;
 333                                                 Label label = new Label ();
 334                                                 label.Text = NullDisplayText;
 335                                                 controls.Add (label);
 336                                         } else
 337                                                 value = NullImageUrl;
 338                                 }
 339                                 img.ImageUrl = value;
 340                                 img.AlternateText = GetFormattedAlternateText (namingContainer);
 341                         }
 342                 }
 343
 344                 public override void ValidateSupportsCallback ()
 345                 {
 346                 }
 347
 348                 protected override DataControlField CreateField ()
 349                 {
 350                         return new ImageField ();
 351                 }
 352
 353                 protected override void CopyProperties (DataControlField newField)
 354                 {
 355                         base.CopyProperties (newField);
 356                         ImageField field = (ImageField) newField;
 357                         field.AlternateText = AlternateText;
 358                         field.ConvertEmptyStringToNull = ConvertEmptyStringToNull;
 359                         field.DataAlternateTextField = DataAlternateTextField;
 360                         field.DataAlternateTextFormatString = DataAlternateTextFormatString;
 361                         field.DataImageUrlField = DataImageUrlField;
 362                         field.DataImageUrlFormatString = DataImageUrlFormatString;
 363                         field.NullDisplayText = NullDisplayText;
 364                         field.NullImageUrl = NullImageUrl;
 365                         field.ReadOnly = ReadOnly;
 366                 }
 367         }
 368 }