class/System.Drawing/System.Drawing/ImageConverter.cs

   1 //
   2 // System.Drawing.ImageConverter.cs
   3 //
   4 // Author:
   5 //   Dennis Hayes (dennish@Raytek.com)
   6 //   Sanjay Gupta (gsanjay@novell.com)
   7 //
   8 // (C) 2002 Ximian, Inc
   9 //
  10
  11 //
  12 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System;
  35 using System.ComponentModel;
  36 using System.Globalization;
  37 using System.IO;
  38 using System.Drawing.Imaging;
  39
  40 namespace System.Drawing
  41 {
  42         /// <summary>
  43         /// Summary description for ImageConverter.
  44         /// </summary>
  45         public class ImageConverter : TypeConverter
  46         {
  47                 public ImageConverter ()
  48                 {
  49                 }
  50
  51                 public override bool CanConvertFrom (ITypeDescriptorContext context, Type sourceType)
  52                 {
  53                         if (sourceType == typeof (System.Byte []))
  54                                 return true;
  55                         else
  56                                 return false;
  57                 }
  58
  59                 public override bool CanConvertTo (ITypeDescriptorContext context, Type destinationType)
  60                 {
  61                         if ((destinationType == typeof (System.Byte [])) || (destinationType == typeof (System.String)))
  62                                 return true;
  63                         else
  64                                 return false;
  65                 }
  66
  67                 public override object ConvertFrom (ITypeDescriptorContext context, CultureInfo culture, object value)
  68                 {
  69                         byte [] bytes = value as byte [];
  70                         if (bytes == null)
  71                                 return base.ConvertFrom (context, culture, value);
  72
  73                         MemoryStream ms = new MemoryStream (bytes);
  74
  75                         return Image.FromStream (ms);
  76                 }
  77
  78                 public override object ConvertTo (ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
  79                 {
  80                         if (value == null)
  81                                 return "(none)";
  82
  83                         if (value is System.Drawing.Image) {
  84                                 if (destinationType == typeof (string)) {
  85                                         return value.ToString ();
  86                                 } else if (CanConvertTo (null, destinationType)) {
  87                                         //came here means destinationType is byte array ;
  88                                         MemoryStream ms = new MemoryStream ();
  89                                         ((Image)value).Save (ms, ((Image)value).RawFormat);
  90                                         return ms.GetBuffer ();
  91                                 }
  92                         }
  93
  94                         string msg = Locale.GetText ("ImageConverter can not convert from type '{0}'.", value.GetType ());
  95                         throw new NotSupportedException (msg);
  96                 }
  97
  98                 public override PropertyDescriptorCollection GetProperties (ITypeDescriptorContext context, object value, Attribute[] attributes)
  99                 {
 100                         return TypeDescriptor.GetProperties (typeof (Image), attributes);
 101                 }
 102
 103                 public override bool GetPropertiesSupported (ITypeDescriptorContext context )
 104                 {
 105                         return true;
 106                 }
 107         }
 108 }