public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
{
if (value is string strValue)
{
return(ColorConverterCommon.ConvertFromString(strValue, culture ?? CultureInfo.CurrentCulture));
}
return(base.ConvertFrom(context, culture, value));
}
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
{
string strValue = value as string;
if (strValue != null)
{
return(ColorConverterCommon.ConvertFromString(strValue, culture));
}
return(base.ConvertFrom(context, culture, value));
}
public static Color FromHtml(string htmlColor)
{
if (string.IsNullOrEmpty(htmlColor))
{
return(Color.Empty);
}
switch (htmlColor.ToLowerInvariant())
{
case "buttonface":
case "threedface":
return(SystemColors.Control);
case "buttonhighlight":
case "threedlightshadow":
return(SystemColors.ControlLightLight);
case "buttonshadow":
return(SystemColors.ControlDark);
case "captiontext":
return(SystemColors.ActiveCaptionText);
case "threeddarkshadow":
return(SystemColors.ControlDarkDark);
case "threedhighlight":
return(SystemColors.ControlLight);
case "background":
return(SystemColors.Desktop);
case "buttontext":
return(SystemColors.ControlText);
case "infobackground":
return(SystemColors.Info);
// special case for Color.LightGray versus html's LightGrey (#340917)
case "lightgrey":
return(Color.LightGray);
}
if (htmlColor[0] == '#' && htmlColor.Length == 4)
{
char r = htmlColor[1], g = htmlColor[2], b = htmlColor[3];
htmlColor = new string(new char[] { '#', r, r, g, g, b, b });
}
#if NETCORE
return(ColorConverterCommon.ConvertFromString(htmlColor, CultureInfo.CurrentCulture));
#else
TypeConverter converter = TypeDescriptor.GetConverter(typeof(Color));
return((Color)converter.ConvertFromString(htmlColor));
#endif
}
/// <summary>
/// Translates an Html color representation to a GDI+ <see cref='Color'/>.
/// </summary>
public static Color FromHtml(string htmlColor)
{
Color c = Color.Empty;
// empty color
if ((htmlColor == null) || (htmlColor.Length == 0))
{
return(c);
}
// #RRGGBB or #RGB
if ((htmlColor[0] == '#') &&
((htmlColor.Length == 7) || (htmlColor.Length == 4)))
{
if (htmlColor.Length == 7)
{
c = Color.FromArgb(Convert.ToInt32(htmlColor.Substring(1, 2), 16),
Convert.ToInt32(htmlColor.Substring(3, 2), 16),
Convert.ToInt32(htmlColor.Substring(5, 2), 16));
}
else
{
string r = char.ToString(htmlColor[1]);
string g = char.ToString(htmlColor[2]);
string b = char.ToString(htmlColor[3]);
c = Color.FromArgb(Convert.ToInt32(r + r, 16),
Convert.ToInt32(g + g, 16),
Convert.ToInt32(b + b, 16));
}
}
// special case. Html requires LightGrey, but .NET uses LightGray
if (c.IsEmpty && string.Equals(htmlColor, "LightGrey", StringComparison.OrdinalIgnoreCase))
{
c = Color.LightGray;
}
// System color
if (c.IsEmpty)
{
if (s_htmlSysColorTable == null)
{
InitializeHtmlSysColorTable();
}
s_htmlSysColorTable !.TryGetValue(htmlColor.ToLowerInvariant(), out c);
}
// resort to type converter which will handle named colors
if (c.IsEmpty)
{
try
{
c = ColorConverterCommon.ConvertFromString(htmlColor, CultureInfo.CurrentCulture);
}
catch (Exception ex)
{
throw new ArgumentException(ex.Message, nameof(htmlColor), ex);
}
}
return(c);
}
/// <summary>
/// Translates an Html color representation to a GDI+ <see cref='Color'/>.
/// </summary>
public static Color FromHtml(string htmlColor)
{
Color c = Color.Empty;
// empty color
if ((htmlColor == null) || (htmlColor.Length == 0))
{
return(c);
}
// #RRGGBB or #RGB
if ((htmlColor[0] == '#') &&
((htmlColor.Length == 7) || (htmlColor.Length == 4)))
{
if (htmlColor.Length == 7)
{
c = Color.FromArgb(Convert.ToInt32(htmlColor.Substring(1, 2), 16),
Convert.ToInt32(htmlColor.Substring(3, 2), 16),
Convert.ToInt32(htmlColor.Substring(5, 2), 16));
}
else
{
string r = Char.ToString(htmlColor[1]);
string g = Char.ToString(htmlColor[2]);
string b = Char.ToString(htmlColor[3]);
c = Color.FromArgb(Convert.ToInt32(r + r, 16),
Convert.ToInt32(g + g, 16),
Convert.ToInt32(b + b, 16));
}
}
// special case. Html requires LightGrey, but .NET uses LightGray
if (c.IsEmpty && String.Equals(htmlColor, "LightGrey", StringComparison.OrdinalIgnoreCase))
{
c = Color.LightGray;
}
// System color
if (c.IsEmpty)
{
if (s_htmlSysColorTable == null)
{
InitializeHtmlSysColorTable();
}
object o = s_htmlSysColorTable[htmlColor.ToLower(CultureInfo.InvariantCulture)];
if (o != null)
{
c = (Color)o;
}
}
// resort to type converter which will handle named colors
if (c.IsEmpty)
{
c = ColorConverterCommon.ConvertFromString(htmlColor, CultureInfo.CurrentCulture);
}
return(c);
}
