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

   1
   2 //
   3 // Permission is hereby granted, free of charge, to any person obtaining
   4 // a copy of this software and associated documentation files (the
   5 // "Software"), to deal in the Software without restriction, including
   6 // without limitation the rights to use, copy, modify, merge, publish,
   7 // distribute, sublicense, and/or sell copies of the Software, and to
   8 // permit persons to whom the Software is furnished to do so, subject to
   9 // the following conditions:
  10 //
  11 // The above copyright notice and this permission notice shall be
  12 // included in all copies or substantial portions of the Software.
  13 //
  14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  18 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  19 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  20 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21 //
  22 /**\r
  23  * Namespace: System.Web.UI.WebControls\r
  24  * Class:     WebColorConverter\r
  25  *\r
  26  * Author:  Gaurav Vaish, Gonzalo Paniagua Javier\r
  27  * Maintainer: gvaish@iitk.ac.in\r
  28  * Contact: <my_scripts2001@yahoo.com>, <gvaish@iitk.ac.in>, <gonzalo@ximian.com>\r
  29  * Implementation: yes\r
  30  * Status:  100%\r
  31  *\r
  32  * (C) Gaurav Vaish (2002)\r
  33  * (c) 2002 Ximian, Inc. (http://www.ximian.com)\r
  34  */\r
  35 \r
  36 using System;\r
  37 using System.Globalization;\r
  38 using System.ComponentModel;\r
  39 using System.Drawing;\r
  40 using System.Web;\r
  41 using System.Web.UI;\r
  42 \r
  43 namespace System.Web.UI.WebControls\r
  44 {\r
  45         public class WebColorConverter : ColorConverter\r
  46         {\r
  47                 public override object ConvertFrom (ITypeDescriptorContext context,\r
  48                                                     CultureInfo culture,\r
  49                                                     object value)\r
  50                 {\r
  51                         if (value is string) {\r
  52                                 string val = ((string) value).Trim ();\r
  53                                 if(val == String.Empty || val.Length == 0)\r
  54                                         return Color.Empty;\r
  55 \r
  56                                 NumberStyles style = (val [0] == '#') ? NumberStyles.HexNumber :\r
  57                                                                        NumberStyles.None;\r
  58 \r
  59                                 try {\r
  60                                         int n = Int32.Parse (val.Substring (1), style);\r
  61                                         return Color.FromArgb (n);\r
  62                                 } catch {\r
  63                                         Color c = Color.FromName (val);\r
  64                                         if (c.A != 0 || c.R != 0 || c.B != 0 || c.G != 0)\r
  65                                                 return c;\r
  66                                 }\r
  67                         }\r
  68 \r
  69                         return base.ConvertFrom(context, culture, value);\r
  70                 }\r
  71 \r
  72                 public override object ConvertTo (ITypeDescriptorContext context,\r
  73                                                   CultureInfo culture,\r
  74                                                   object value,\r
  75                                                   Type destinationType)\r
  76                 {\r
  77                         if (destinationType == null)\r
  78                                 throw new ArgumentNullException ("destinationType");\r
  79 \r
  80                         if (destinationType == typeof (String) && value != null) {\r
  81                                 Color c = (Color) value;\r
  82                                 if (c == Color.Empty)\r
  83                                         return String.Empty;\r
  84 \r
  85                                 if (c.IsNamedColor || c.IsSystemColor)\r
  86                                         return c.Name;\r
  87 \r
  88                                 return String.Format ("#{0:X2}{1:X2}{2:X2}{3:X2}", c.A, c.R, c.G, c.B);\r
  89                         }\r
  90 \r
  91                         return base.ConvertTo(context, culture, value, destinationType);\r
  92                 }\r
  93         }\r
  94 }\r
  95 \r