mcs/class/System.Drawing/System.Drawing/ColorTranslator.cs

   1 //
   2 // System.Drawing.ColorTranslator.cs
   3 //
   4 // Authors:
   5 //      Dennis Hayes (dennish@raytek.com)
   6 //      Ravindra (rkumar@novell.com)
   7 //      Sebastien Pouliot  <sebastien@ximian.com>
   8 //
   9 // Copyright (C) 2001 Ximian, Inc.  http://www.ximian.com
  10 // Copyright (C) 2004,2006-2007 Novell, Inc (http://www.novell.com)
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.ComponentModel;
  33 using System.Globalization;
  34
  35 namespace System.Drawing {
  36
  37         public sealed class ColorTranslator {
  38
  39                 private ColorTranslator ()
  40                 {
  41                 }
  42
  43                 public static Color FromHtml (string htmlColor)
  44                 {
  45                         if ((htmlColor == null) || (htmlColor.Length == 0))
  46                                 return Color.Empty;
  47
  48                         switch (htmlColor.ToLowerInvariant ()) {
  49                         case "buttonface":
  50                         case "threedface":
  51                                 return SystemColors.Control;
  52                         case "buttonhighlight":
  53                         case "threedlightshadow":
  54                                 return SystemColors.ControlLightLight;
  55                         case "buttonshadow":
  56                                 return SystemColors.ControlDark;
  57                         case "captiontext":
  58                                 return SystemColors.ActiveCaptionText;
  59                         case "threeddarkshadow":
  60                                 return SystemColors.ControlDarkDark;
  61                         case "threedhighlight":
  62                                 return SystemColors.ControlLight;
  63                         case "background":
  64                                 return SystemColors.Desktop;
  65                         case "buttontext":
  66                                 return SystemColors.ControlText;
  67                         case "infobackground":
  68                                 return SystemColors.Info;
  69                         // special case for Color.LightGray versus html's LightGrey (#340917)
  70                         case "lightgrey":
  71                                 return Color.LightGray;
  72                         }
  73
  74                         TypeConverter converter = TypeDescriptor.GetConverter (typeof (Color));
  75                         return (Color) converter.ConvertFromString (htmlColor);
  76                 }
  77
  78                 internal static Color FromBGR (int bgr)
  79                 {
  80                         Color result = Color.FromArgb (0xFF, (bgr & 0xFF), ((bgr >> 8) & 0xFF), ((bgr >> 16) & 0xFF));
  81                         Color known = KnownColors.FindColorMatch (result);
  82                         return (known.IsEmpty) ? result : known;
  83                 }
  84
  85                 public static Color FromOle (int oleColor)
  86                 {
  87                         // OleColor format is BGR
  88                         return FromBGR (oleColor);
  89                 }
  90
  91                 public static Color FromWin32 (int win32Color)
  92                 {
  93                         // Win32Color format is BGR
  94                         return FromBGR (win32Color);
  95                 }
  96
  97                 public static string ToHtml (Color c)
  98                 {
  99                         if (c.IsEmpty)
 100                                 return String.Empty;
 101
 102                         if (c.IsSystemColor) {
 103                                 KnownColor kc = c.ToKnownColor ();
 104                                 switch (kc) {
 105                                 case KnownColor.ActiveBorder:
 106                                 case KnownColor.ActiveCaption:
 107                                 case KnownColor.AppWorkspace:
 108                                 case KnownColor.GrayText:
 109                                 case KnownColor.Highlight:
 110                                 case KnownColor.HighlightText:
 111                                 case KnownColor.InactiveBorder:
 112                                 case KnownColor.InactiveCaption:
 113                                 case KnownColor.InactiveCaptionText:
 114                                 case KnownColor.InfoText:
 115                                 case KnownColor.Menu:
 116                                 case KnownColor.MenuText:
 117                                 case KnownColor.ScrollBar:
 118                                 case KnownColor.Window:
 119                                 case KnownColor.WindowFrame:
 120                                 case KnownColor.WindowText:
 121                                         return KnownColors.GetName (kc).ToLower (CultureInfo.InvariantCulture);
 122
 123                                 case KnownColor.ActiveCaptionText:
 124                                         return "captiontext";
 125                                 case KnownColor.Control:
 126                                         return "buttonface";
 127                                 case KnownColor.ControlDark:
 128                                         return "buttonshadow";
 129                                 case KnownColor.ControlDarkDark:
 130                                         return "threeddarkshadow";
 131                                 case KnownColor.ControlLight:
 132                                         return "buttonface";
 133                                 case KnownColor.ControlLightLight:
 134                                         return "buttonhighlight";
 135                                 case KnownColor.ControlText:
 136                                         return "buttontext";
 137                                 case KnownColor.Desktop:
 138                                         return "background";
 139                                 case KnownColor.HotTrack:
 140                                         return "highlight";
 141                                 case KnownColor.Info:
 142                                         return "infobackground";
 143
 144                                 default:
 145                                         return String.Empty;
 146                                 }
 147                         }
 148
 149                         if (c.IsNamedColor) {
 150                                 if (c == Color.LightGray)
 151                                         return "LightGrey";
 152                                 else
 153                                         return c.Name;
 154                         }
 155
 156                         return FormatHtml (c.R, c.G, c.B);
 157                 }
 158
 159                 static char GetHexNumber (int b)
 160                 {
 161                         return (char) (b > 9 ? 55 + b : 48 + b);
 162                 }
 163
 164                 static string FormatHtml (int r, int g, int b)
 165                 {
 166                         char [] htmlColor = new char [7];
 167                         htmlColor [0] = '#';
 168                         htmlColor [1] = GetHexNumber ((r >> 4) & 15);
 169                         htmlColor [2] = GetHexNumber (r & 15);
 170                         htmlColor [3] = GetHexNumber ((g >> 4) & 15);
 171                         htmlColor [4] = GetHexNumber (g & 15);
 172                         htmlColor [5] = GetHexNumber ((b >> 4) & 15);
 173                         htmlColor [6] = GetHexNumber (b & 15);
 174
 175                         return new string (htmlColor);
 176                 }
 177
 178                 public static int ToOle (Color c)
 179                 {
 180                         // OleColor format is BGR, same as Win32
 181                         return  ((c.B << 16) | (c.G << 8) | c.R);
 182                 }
 183
 184                 public static int ToWin32 (Color c)
 185                 {
 186                         // Win32Color format is BGR, Same as OleColor
 187                         return  ((c.B << 16) | (c.G << 8) | c.R);
 188                 }
 189         }
 190 }