Where have all the colors gone?

If you are programming in Silverlight, you probably have seen all the colors available in the XAML. Want a line that is AliceBlue, no problem, but if you want to create the same line programatically in C#, good luck.

The Colors class is just a small subset of all the HTML named colors, so the only way to add AliceBlue is to use Color.FromArgb, so you go out to a website that lists all the colors' RGB values. AliceBlue is #F0F8FF, so you paste the RGB value into Color.FromArgb.

But wait! Color.FromArgb expects 4 bytes, not a single number (The first byte is the Alpha value - i.e. the transparentcy of the color, hence the A in front of the RGB) and our color is only 3 bytes. We can add #FF in front of #F0F8FF but Color.FromArgb expects them to be separate values separated by a comma.

Color.FromArgb(#FF, #F0, #F8, #FF) will not work because C# does not recognize them as numbers. The key to having C# recognize them as hex numbers is to replace the hash(#) with 0x. So AliceBlue is now Color.FromArgb(0xFF, 0xF0, 0xF8, 0xFF).

Too much work you say? I agree. I just want to use my named colors. So, I created my own Color class that in Silverlight will output named colors!

The code looks like this:


private class MyColors
{
    public static Color Aliceblue
    {
        get
        {
            return GenerateColorStruct(0xFFF0F8FF);
        }
    }

    .
    .
    .

    private static Color GenerateColorStruct
                                    (uint color)
    {
        var mask = 0x000000FF;
        var returnval = new Color
        {
            A = ((byte)((color >> 24) & mask)),
            R = ((byte)((color >> 16) & mask)),
            G = ((byte)((color >> 8) & mask)),
            B = ((byte)((color) & mask))
        };

        return returnval;
    }
}

The entire .cs file can be found here. Since this is a private class that you can add to any Silverlight page.cs file that needs named colors , you can also add your own named colors that you want to use all the time!

You can also compile it to its own dll, but I like it better in the page.cs file. For size of outputs sake, right before you publish you can remove all the unused colors.