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 (string.IsNullOrEmpty (htmlColor)) return Color.Empty;
  46
  47                         switch (htmlColor.ToLowerInvariant ()) {
  48                         case "buttonface":
  49                         case "threedface":
  50                                 return SystemColors.Control;
  51                         case "buttonhighlight":
  52                         case "threedlightshadow":
  53                                 return SystemColors.ControlLightLight;
  54                         case "buttonshadow":
  55                                 return SystemColors.ControlDark;
  56                         case "captiontext":
  57                                 return SystemColors.ActiveCaptionText;
  58                         case "threeddarkshadow":
  59                                 return SystemColors.ControlDarkDark;
  60                         case "threedhighlight":
  61                                 return SystemColors.ControlLight;
  62                         case "background":
  63                                 return SystemColors.Desktop;
  64                         case "buttontext":
  65                                 return SystemColors.ControlText;
  66                         case "infobackground":
  67                                 return SystemColors.Info;
  68                         // special case for Color.LightGray versus html's LightGrey (#340917)
  69                         case "lightgrey":
  70                                 return Color.LightGray;
  71                         }
  72
  73                         if (htmlColor[0] == '#' && htmlColor.Length == 4)
  74                         {
  75                                 char r = htmlColor[1], g = htmlColor[2], b = htmlColor[3];
  76                                 htmlColor = new string ( new char [] { '#', r, r, g, g, b, b } );
  77                         }
  78
  79                         TypeConverter converter = TypeDescriptor.GetConverter (typeof (Color));
  80                         return (Color) converter.ConvertFromString (htmlColor);
  81                 }
  82
  83                 internal static Color FromBGR (int bgr)
  84                 {
  85                         Color result = Color.FromArgb (0xFF, (bgr & 0xFF), ((bgr >> 8) & 0xFF), ((bgr >> 16) & 0xFF));
  86                         Color known = KnownColors.FindColorMatch (result);
  87                         return (known.IsEmpty) ? result : known;
  88                 }
  89
  90                 public static Color FromOle (int oleColor)
  91                 {
  92                         // OleColor format is BGR
  93                         return FromBGR (oleColor);
  94                 }
  95
  96                 public static Color FromWin32 (int win32Color)
  97                 {
  98                         // Win32Color format is BGR
  99                         return FromBGR (win32Color);
 100                 }
 101
 102                 public static string ToHtml (Color c)
 103                 {
 104                         if (c.IsEmpty)
 105                                 return String.Empty;
 106
 107                         if (c.IsSystemColor) {
 108                                 KnownColor kc = c.ToKnownColor ();
 109                                 switch (kc) {
 110                                 case KnownColor.ActiveBorder:
 111                                 case KnownColor.ActiveCaption:
 112                                 case KnownColor.AppWorkspace:
 113                                 case KnownColor.GrayText:
 114                                 case KnownColor.Highlight:
 115                                 case KnownColor.HighlightText:
 116                                 case KnownColor.InactiveBorder:
 117                                 case KnownColor.InactiveCaption:
 118                                 case KnownColor.InactiveCaptionText:
 119                                 case KnownColor.InfoText:
 120                                 case KnownColor.Menu:
 121                                 case KnownColor.MenuText:
 122                                 case KnownColor.ScrollBar:
 123                                 case KnownColor.Window:
 124                                 case KnownColor.WindowFrame:
 125                                 case KnownColor.WindowText:
 126                                         return KnownColors.GetName (kc).ToLower (CultureInfo.InvariantCulture);
 127
 128                                 case KnownColor.ActiveCaptionText:
 129                                         return "captiontext";
 130                                 case KnownColor.Control:
 131                                         return "buttonface";
 132                                 case KnownColor.ControlDark:
 133                                         return "buttonshadow";
 134                                 case KnownColor.ControlDarkDark:
 135                                         return "threeddarkshadow";
 136                                 case KnownColor.ControlLight:
 137                                         return "buttonface";
 138                                 case KnownColor.ControlLightLight:
 139                                         return "buttonhighlight";
 140                                 case KnownColor.ControlText:
 141                                         return "buttontext";
 142                                 case KnownColor.Desktop:
 143                                         return "background";
 144                                 case KnownColor.HotTrack:
 145                                         return "highlight";
 146                                 case KnownColor.Info:
 147                                         return "infobackground";
 148
 149                                 default:
 150                                         return String.Empty;
 151                                 }
 152                         }
 153
 154                         if (c.IsNamedColor) {
 155                                 if (c == Color.LightGray)
 156                                         return "LightGrey";
 157                                 else
 158                                         return c.Name;
 159                         }
 160
 161                         return FormatHtml (c.R, c.G, c.B);
 162                 }
 163
 164                 static char GetHexNumber (int b)
 165                 {
 166                         return (char) (b > 9 ? 55 + b : 48 + b);
 167                 }
 168
 169                 static string FormatHtml (int r, int g, int b)
 170                 {
 171                         char [] htmlColor = new char [7];
 172                         htmlColor [0] = '#';
 173                         htmlColor [1] = GetHexNumber ((r >> 4) & 15);
 174                         htmlColor [2] = GetHexNumber (r & 15);
 175                         htmlColor [3] = GetHexNumber ((g >> 4) & 15);
 176                         htmlColor [4] = GetHexNumber (g & 15);
 177                         htmlColor [5] = GetHexNumber ((b >> 4) & 15);
 178                         htmlColor [6] = GetHexNumber (b & 15);
 179
 180                         return new string (htmlColor);
 181                 }
 182
 183                 public static int ToOle (Color c)
 184                 {
 185                         // OleColor format is BGR, same as Win32
 186                         return  ((c.B << 16) | (c.G << 8) | c.R);
 187                 }
 188
 189                 public static int ToWin32 (Color c)
 190                 {
 191                         // Win32Color format is BGR, Same as OleColor
 192                         return  ((c.B << 16) | (c.G << 8) | c.R);
 193                 }
 194         }
 195 }