public void ToColorTest()
{
List <Tuple <string, Color?> > tests = new List <Tuple <string, Color?> >
{
Tuple.Create <string, Color?>("", null),
Tuple.Create <string, Color?>("White", Color.White),
Tuple.Create <string, Color?>("WHITE", Color.White),
Tuple.Create <string, Color?>(" white ", Color.White),
Tuple.Create <string, Color?>("#fff", Color.White),
Tuple.Create <string, Color?>("fcd", Color.FromArgb(0xff, 0xcc, 0xdd)),
Tuple.Create <string, Color?>("ffeedd", Color.FromArgb(0xff, 0xee, 0xdd)),
Tuple.Create <string, Color?>("#111111", Color.FromArgb(0x11, 0x11, 0x11)),
Tuple.Create <string, Color?>("rgb(1,2,3)", Color.FromArgb(1, 2, 3)),
Tuple.Create <string, Color?>("rgb( 1, 2, 3)", Color.FromArgb(1, 2, 3)),
Tuple.Create <string, Color?>("rgba(2, 3, 4, 1.0)", Color.FromArgb(255, 2, 3, 4)),
Tuple.Create <string, Color?>("hsl(120, 100%, 50%)", ColorExtensions.FromHsl(1.0 / 3.0, 1.0, 0.5)),
Tuple.Create <string, Color?>("hsl(360, 10%, 25%)", ColorExtensions.FromHsl(0, .1, .25)),
Tuple.Create <string, Color?>("hsla(30, 10%, 25%, 0.5)", ColorExtensions.FromAhsl(0.5, 1.0 / 12.0, .1, .25)),
};
foreach (var t in tests)
{
var expected = t.Item2;
var actual = t.Item1.ToColor();
if (!actual.HasValue)
{
Assert.IsNull(expected, "Color: " + t.Item1);
}
else
{
Assert.IsNotNull(expected, "Color: " + t.Item1);
Assert.IsTrue(expected.Value.R == actual.Value.R &&
expected.Value.G == actual.Value.G &&
expected.Value.B == actual.Value.B,
"Color: " + t.Item1);
}
}
}
public static Color?ToColor(this string str, bool htmlSafe = false)
{
if (string.IsNullOrWhiteSpace(str))
{
return(null);
}
str = str.Trim();
if (str.StartsWith("#"))
{
str = str.Substring(1);
}
else if (str.StartsWith("rgb("))
{
var parts = str.Substring("rgb(".Length).Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
if (parts.Length != 3)
{
return(null);
}
int r = parts[0].ToInt32();
int g = parts[1].ToInt32();
int b = parts[2].ToInt32();
if (r < 0 || r > 255 || g < 0 || g > 255 || b < 0 || b > 255)
{
return(null);
}
return(Color.FromArgb(r, g, b));
}
else if (str.StartsWith("rgba("))
{
var parts = str.Substring("rgba(".Length).Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
if (parts.Length != 4)
{
return(null);
}
int r = parts[0].ToInt32();
int g = parts[1].ToInt32();
int b = parts[2].ToInt32();
int a = (int)(255 * parts[3].ToDouble());
if (r < 0 || r > 255 || g < 0 || g > 255 || b < 0 || b > 255 || a < 0 || a > 255)
{
return(null);
}
return(Color.FromArgb(a, r, g, b));
}
else if (str.StartsWith("hsl("))
{
var parts = str.Substring("hsl(".Length).Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
if (parts.Length != 3)
{
return(null);
}
double h = parts[0].ToDouble() / 360.0;
double s = parts[1].ToDouble();
double l = parts[2].ToDouble();
// h can be any value actually, since it gets converted to 0-360 (wheel of color)
if (s < 0 || s > 1 || l < 0 || l > 1)
{
return(null);
}
return(ColorExtensions.FromHsl(h, s, l));
}
else if (str.StartsWith("hsla("))
{
var parts = str.Substring("hsla(".Length).Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
if (parts.Length != 4)
{
return(null);
}
double h = parts[0].ToDouble() / 360.0;
double s = parts[1].ToDouble();
double l = parts[2].ToDouble();
double a = parts[3].ToDouble();
if (s < 0 || s > 1 || l < 0 || l > 1 || a < 0 || a > 1)
{
return(null);
}
return(ColorExtensions.FromAhsl(a, h, s, l));
}
else
{
try
{
var color = Color.FromName(str);
if (!(color.R == 0 && color.G == 0 && color.B == 0 && color.A == 0) || string.Compare(str, "black", true) == 0)
{
return(color);
}
}
catch (Exception)
{
}
if (htmlSafe)
{
return(null); // must be either a named color or start with #/rgb to be HTML safe
}
}
if (str.Length == 3)
{
str = string.Concat(str[0], str[0], str[1], str[1], str[2], str[2]);
}
else if (str.Length != 6)
{
return(null);
}
byte[] bytes = str.HexStringToBytes();
if (bytes == null || bytes.Length != 3)
{
return(null);
}
return(Color.FromArgb(bytes[0], bytes[1], bytes[2]));
}