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

   1 /**\r
   2  * Namespace: System.Web.UI.WebControls\r
   3  * Class:     WebColorConverter\r
   4  *\r
   5  * Author:  Gaurav Vaish, Gonzalo Paniagua Javier\r
   6  * Maintainer: gvaish@iitk.ac.in\r
   7  * Contact: <my_scripts2001@yahoo.com>, <gvaish@iitk.ac.in>, <gonzalo@ximian.com>\r
   8  * Implementation: yes\r
   9  * Status:  100%\r
  10  *\r
  11  * (C) Gaurav Vaish (2002)\r
  12  * (c) 2002 Ximian, Inc. (http://www.ximian.com)\r
  13  */\r
  14 \r
  15 using System;\r
  16 using System.Globalization;\r
  17 using System.ComponentModel;\r
  18 using System.Drawing;\r
  19 using System.Web;\r
  20 using System.Web.UI;\r
  21 \r
  22 namespace System.Web.UI.WebControls\r
  23 {\r
  24         public class WebColorConverter : ColorConverter\r
  25         {\r
  26                 public override object ConvertFrom (ITypeDescriptorContext context,\r
  27                                                     CultureInfo culture,\r
  28                                                     object value)\r
  29                 {\r
  30                         if (value is string) {\r
  31                                 string val = ((string) value).Trim ();\r
  32                                 if(val == String.Empty || val.Length == 0)\r
  33                                         return Color.Empty;\r
  34 \r
  35                                 NumberStyles style = (val [0] == '#') ? NumberStyles.HexNumber :\r
  36                                                                        NumberStyles.None;\r
  37 \r
  38                                 try {\r
  39                                         int n = Int32.Parse (val.Substring (1), style);\r
  40                                         return Color.FromArgb (n);\r
  41                                 } catch {\r
  42                                         Color c = Color.FromName (val);\r
  43                                         if (c.A != 0 || c.R != 0 || c.B != 0 || c.G != 0)\r
  44                                                 return c;\r
  45                                 }\r
  46                         }\r
  47 \r
  48                         return base.ConvertFrom(context, culture, value);\r
  49                 }\r
  50 \r
  51                 public override object ConvertTo (ITypeDescriptorContext context,\r
  52                                                   CultureInfo culture,\r
  53                                                   object value,\r
  54                                                   Type destinationType)\r
  55                 {\r
  56                         if (destinationType == null)\r
  57                                 throw new ArgumentNullException ("destinationType");\r
  58 \r
  59                         if (destinationType == typeof (String) && value != null) {\r
  60                                 Color c = (Color) value;\r
  61                                 if (c == Color.Empty)\r
  62                                         return String.Empty;\r
  63 \r
  64                                 if (c.IsNamedColor || c.IsSystemColor)\r
  65                                         return c.Name;\r
  66 \r
  67                                 return String.Format ("#{0:X2}{1:X2}{2:X2}{3:X2}", c.A, c.R, c.G, c.B);\r
  68                         }\r
  69 \r
  70                         return base.ConvertTo(context, culture, value, destinationType);\r
  71                 }\r
  72         }\r
  73 }\r
  74 \r