mcs/class/Managed.Windows.Forms/System.Windows.Forms/DataObject.cs

   1 // Permission is hereby granted, free of charge, to any person obtaining
   2 // a copy of this software and associated documentation files (the
   3 // "Software"), to deal in the Software without restriction, including
   4 // without limitation the rights to use, copy, modify, merge, publish,
   5 // distribute, sublicense, and/or sell copies of the Software, and to
   6 // permit persons to whom the Software is furnished to do so, subject to
   7 // the following conditions:
   8 //
   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  13 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  16 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2005 Novell, Inc. (http://www.novell.com)
  21 //
  22 // Authors:
  23 //      Peter Bartok    (pbartok@novell.com)
  24 //
  25 //
  26
  27 // COMPLETE
  28
  29 using System;
  30 using System.Collections;
  31 using System.Runtime.InteropServices;
  32
  33 namespace System.Windows.Forms {
  34         [ClassInterface(ClassInterfaceType.None)]
  35         public class DataObject : IDataObject {
  36                 #region DataObject.Entry Class
  37                 private class Entry {
  38                         #region Local Variables
  39                         private string  type;
  40                         private object  data;
  41                         private bool    autoconvert;
  42                         internal Entry  next;
  43                         #endregion      // Local Variables
  44
  45                         #region Constructors
  46                         internal Entry(string type, object data, bool autoconvert) {
  47                                 this.type = type;
  48                                 this.data = data;
  49                                 this.autoconvert = autoconvert;
  50                         }
  51                         #endregion      // Constructors
  52
  53                         #region Properties
  54                         public object Data {
  55                                 get {
  56                                         return data;
  57                                 }
  58
  59                                 set {
  60                                         data = value;
  61                                 }
  62                         }
  63                         #endregion      // Properties
  64
  65                         #region Methods
  66                         public static int Count(Entry entries) {
  67                                 int     result;
  68
  69                                 result = 0;
  70
  71                                 while (entries != null) {
  72                                         result++;
  73                                         entries = entries.next;
  74                                 }
  75
  76                                 return result;
  77                         }
  78
  79                         public static Entry Find(Entry entries, string type) {
  80                                 while (entries != null) {
  81                                         if (entries.type.Equals(type)) {
  82                                                 return entries;
  83                                         }
  84                                         entries = entries.next;
  85                                 }
  86
  87                                 return null;
  88                         }
  89
  90                         public static Entry FindConvertible(Entry entries, string type) {
  91                                 Entry e;
  92
  93                                 e = Find(entries, type);
  94                                 if (e != null) {
  95                                         return e;
  96                                 }
  97
  98                                 e = entries;
  99                                 while (e != null) {
 100                                         if (type == DataFormats.Text) {
 101                                                 if (e.type == DataFormats.UnicodeText) {
 102                                                         return e;
 103                                                 }
 104                                         } else if (type == DataFormats.UnicodeText) {
 105                                                 if (e.type == DataFormats.Text) {
 106                                                         return e;
 107                                                 }
 108                                         } else if (type == DataFormats.StringFormat) {
 109                                                 if (e.type == DataFormats.Text) {
 110                                                         return e;
 111                                                 } else if (e.type == DataFormats.UnicodeText) {
 112                                                         return e;
 113                                                 }
 114                                         }
 115                                         e = e.next;
 116                                 }
 117
 118                                 return null;
 119                         }
 120
 121                         public static string[] Entries(Entry entries, bool convertible) {
 122                                 Entry           e;
 123                                 ArrayList       list;
 124                                 string[]        result;
 125
 126                                 // Initially store into something that we can grow easily
 127                                 list = new ArrayList(Entry.Count(entries));
 128                                 e = entries;
 129
 130                                 while (e != null) {
 131                                         list.Add(e.type);
 132                                         e = e.next;
 133                                 }
 134
 135                                 if (convertible) {
 136                                         // Add the convertibles
 137                                         if ((Entry.Find(entries, DataFormats.Text) != null) && (Entry.Find(entries, DataFormats.UnicodeText) == null)) {
 138                                                 list.Add(DataFormats.UnicodeText);
 139                                         }
 140
 141                                         if ((Entry.Find(entries, DataFormats.Text) == null) && (Entry.Find(entries, DataFormats.UnicodeText) != null)) {
 142                                                 list.Add(DataFormats.Text);
 143                                         }
 144
 145                                         if (((Entry.Find(entries, DataFormats.Text) != null) || (Entry.Find(entries, DataFormats.UnicodeText) != null)) && (Entry.Find(entries, DataFormats.StringFormat) == null)) {
 146                                                 list.Add(DataFormats.StringFormat);
 147                                         }
 148                                 }
 149
 150                                 // Copy the results into a string array
 151                                 result = new string[list.Count];
 152                                 for (int i = 0; i < list.Count; i++) {
 153                                         result[i] = (string)list[i];
 154                                 }
 155
 156                                 return result;
 157                         }
 158                         #endregion      // Methods
 159                 }
 160                 #endregion      // DataObject.Entry class
 161
 162                 #region Local Variables
 163                 private Entry   entries;
 164                 #endregion      // Local Variables
 165
 166                 #region Public Constructors
 167                 public DataObject() {
 168                         entries = null;
 169                 }
 170
 171                 public DataObject(object data) {
 172                         SetData(data);
 173                 }
 174
 175                 public DataObject(string format, object data) {
 176                         SetData(format, data);
 177                 }
 178                 #endregion      // Public Constructors
 179
 180                 #region Public Instance Properties
 181                 public virtual object GetData(string format) {
 182                         return GetData(format, true);
 183                 }
 184
 185                 public virtual object GetData(string format, bool autoConvert) {
 186                         Entry e;
 187                         if (autoConvert) {
 188                                 e = Entry.FindConvertible(entries, format);
 189                         } else {
 190                                 e = Entry.Find(entries, format);
 191                         }
 192                         if (e == null)
 193                                 return null;
 194                         return e.Data;
 195                 }
 196
 197                 public virtual object GetData(Type format) {
 198                         return GetData(format.FullName, true);
 199                 }
 200
 201                 public virtual bool GetDataPresent(string format) {
 202                         return GetDataPresent(format, true);
 203                 }
 204
 205                 public virtual bool GetDataPresent(string format, bool autoConvert) {
 206                         if (autoConvert) {
 207                                 return Entry.FindConvertible(entries, format) != null;
 208                         } else {
 209                                 return Entry.Find(entries, format) != null;
 210                         }
 211                 }
 212
 213                 public virtual bool GetDataPresent(Type format) {
 214                         return GetDataPresent(format.FullName, true);
 215                 }
 216
 217                 public virtual string[] GetFormats() {
 218                         return GetFormats(true);
 219                 }
 220
 221                 public virtual string[] GetFormats(bool autoConvert) {
 222                         return Entry.Entries(entries, autoConvert);
 223                 }
 224
 225                 public virtual void SetData(object data) {
 226                         SetData(data.GetType(), data);
 227                 }
 228
 229                 public virtual void SetData(string format, bool autoConvert, object data) {
 230                         Entry   entry;
 231                         Entry   e;
 232
 233                         entry = Entry.Find(entries, format);
 234
 235                         if (entry == null) {
 236                                 entry = new DataObject.Entry(format, data, autoConvert);
 237                         } else {
 238                                 entry.Data = data;
 239                                 return;
 240                         }
 241
 242                         lock (this) {
 243                                 if (entries == null) {
 244                                         entries = entry;
 245                                 } else {
 246                                         // Insert into the list of known/defined formats
 247                                         e = entries;
 248
 249                                         while (e.next != null) {
 250                                                 e = e.next;
 251                                         }
 252                                         e.next = entry;
 253                                 }
 254                         }
 255                 }
 256
 257                 public virtual void SetData(string format, object data) {
 258                         SetData(format, true, data);
 259                 }
 260
 261                 public virtual void SetData(Type format, object data) {
 262                         SetData(EnsureFormat(format), true, data);
 263                 }
 264                 #endregion      // Public Instance Properties
 265
 266                 #region Public Instance Methods
 267                 #endregion      // Public Instance Methods
 268
 269                 #region Private Methods
 270                 internal string EnsureFormat(string name) {
 271                         DataFormats.Format f;
 272
 273                         f = DataFormats.Format.Find(name);
 274                         if (f == null) {
 275                                 // Register the format
 276                                 f = DataFormats.Format.Add(name);
 277                         }
 278
 279                         return f.Name;
 280                 }
 281
 282                 internal string EnsureFormat(Type type) {
 283                         return EnsureFormat(type.FullName);
 284                 }
 285
 286                 #endregion      // Private Methods
 287         }
 288 }