Question

So I am using a C# WebBrowser control and am trying to convert a string into an HTML/CSS rainbow. Currently I simply randomly generate 1000 colors in hex format and iterate through each char in the string adding a span style color:(hex value) for each char. It works but I would like the colors to merge together for a more rainbow effect. Is this possible? Here is my current function:

    public static string Rainbow(string text)
    {
        int numColors = 1000;
        var colors = new List<string>();
        var random = new Random();
        for (int i = 0; i < numColors; i++)
        {
            colors.Add(String.Format("#{0:X6}", random.Next(0x1000000)));
        }

        string rainbow = "";
        int index = 0;
        foreach (char c in text)
        {
            rainbow += String.Format("<span style='color: {0};'>{1}</span>", colors[index], c.ToString());

            if (index > numColors)
                index = 0;
            else
                index++;
        }

        return rainbow;
    }

Answer 1

Simple; don’t use Random!

Something like this may help you get started:

for (int i = 0; i < 256; i++)
    {
        colors.Add(String.Format("#{0:X2}{1:X2}00", i, 255-i));
    }

to fade from green to red in 255 steps.

HTH!