.netで#RRGGBB書式←→Color構造体の変換

Color StrToColor(string rgbString)
{
    int r = Convert.ToInt32(rgbString.Substring(1, 2), 16);
    int g = Convert.ToInt32(rgbString.Substring(3, 2), 16);
    int b = Convert.ToInt32(rgbString.Substring(5, 2), 16);
    return Color.FromArgb(r, g, b);
}

string ColorToStr(Color color)
{
    string r = Convert.ToString(color.R, 16);
    string g = Convert.ToString(color.G, 16);
    string b = Convert.ToString(color.B, 16);
    return "#" + r + g + b;
}