从 BBCode 转换为 Markdown

Bbcode2md.cs

    class Bbcode2md
    {   
 
        /// <summary>
        /// To convert bbcode to markdown
        /// </summary>
        /// <remarks>[JonDum/BBCode-To-Markdown-Converter](https://github.com/JonDum/BBCode-To-Markdown-Converter )</remarks>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string BbcodetoMd(string str)
        {
            str = ConvertBold(str);
            str = ConvertItalics(str);
            str = ConvertUnderline(str);
            str = ConvertStrikethrough(str);
            str = ConvertCenter(str);
            str = ConvertQuote(str);
            str = ConvertSize(str);
            str = ConvertColor(str);
            str = ConvertList(str);
            str = ConvertImage(str);
            str = ConvertUrl(str);
            return ConvertCode(str);
        }

        private static string ConvertCode(string str)
        {
            var regex = new Regex(@"\[code\](.*?)\[\/code\]");
            str = regex.Replace(str, "'$1'");

            regex = new Regex(@"\[code\]((?:.|\n)+?)\[\/code\]");
            var t = regex.Match(str);
            if (t.Success)
            {
                str = $@"```
{t.Groups[1].Value}
```";
            }


            return str;
        }

        private static string ConvertUrl(string str)
        {
            var regex = new Regex(@"\[url=(.+?)\]((?:.|\n)+?)\[\/url\]");
            return regex.Replace(str, "[$2]($1)");
        }

        private static string ConvertImage(string str)
        {
            var regex = new Regex(@"\[img\]((?:.|\n)+?)\[\/img\]");
            return regex.Replace(str, "![$1]($1)");
        }

        private static string ConvertList(string str)
        {
            var regex = new Regex(@"\[list\=1\]((?:.|\n)+?)\[\/list\]");
            var t = regex.Match(str);
            if (t.Success)
            {
                str = t.Groups[1].Value.Replace("[*]", "1. ");
            }

            return str;
        }

        private static string ConvertColor(string str)
        {
            var regex = new Regex(@"\[color\=.+?\]((?:.|\n)+?)\[\/color\]");
            List<string> t = new List<string>()
            {
                // list of colors from http://if.invisionfree.com/topic/423042/1/
                "Aliceblue",
                "Antiquewhite",
                "Aqua",
                "Aquamarine",
                "Azure",
                "Beige",
                "Bisque",
                "Black",
                "Blanchedalmond",
                "Blue",
                "Blueviolet",
                "Brown",
                "Burlywood",
                "Cadetblue",
                "Chartreuse",
                "Chocolate",
                "Coral",
                "Cornflowerblue",
                "Cornsilk",
                "Crimson",
                "Cyan",
                "Darkblue",
                "Darkcyan",
                "Darkgoldenrod",
                "Darkgray",
                "Darkgreen",
                "Darkkhaki",
                "Darkmagenta",
                "Darkolivegreen",
                "Darkorange",
                "Darkorchid",
                "Darkred",
                "Darksalmon",
                "Darkseagreen",
                "Darkslateblue",
                "Darkslategray",
                "Darkturquoise",
                "Darkviolet",
                "Deeppink",
                "Deepskyblue",
                "Dimgray",
                "Dodgerblue",
                "Firebrick",
                "Floralwhite",
                "Forestgreen",
                "Fuchsia",
                "Gainsboro",
                "Ghostwhite",
                "Gold",
                "Goldenrod",
                "Gray",
                "Green",
                "Greenyellow",
                "Honeydew",
                "Hotpink",
                "Indianred",
                "Indigo",
                "Ivory",
                "Khaki",
                "Lavender",
                "Lavenderblush",
                "Lawngreen",
                "Lemonchiffon",
                "Lightblue",
                "Lightcoral",
                "Lightcyan",
                "Lightgoldenrodyellow",
                "Lightgray",
                "Lightpink",
                "Lightsalmon",
                "Lightseagreen",
                "Lightskyblue",
                "Lightslategray",
                "Lightsteelblue",
                "Lightyellow",
                "Lime",
                "Limegreen",
                "Linen",
                "Magenta",
                "Maroon",
                "Mediumaquamarine",
                "Mediumblue",
                "Mediumorchid",
                "Mediumpurple",
                "Mediumseagreen",
                "Mediumslateblue",
                "Mediumspringgreen",
                "Mediumturquoise",
                "Mediumvioletred",
                "Midnightblue",
                "Mintcream",
                "Mistyrose",
                "Moccasin",
                "Navajowhite",
                "Navy",
                "Oldlace",
                "Olive",
                "Olivedrab",
                "Orange",
                "Orangered",
                "Orchid",
                "Palegoldenrod",
                "Palegreen",
                "Paleturquoise",
                "Palevioletred",
                "Papayawhip",
                "Peachpuff",
                "Peru",
                "Pink",
                "Plum",
                "Powderblue",
                "Purple",
                "Red",
                "Rosybrown",
                "Royalblue",
                "Saddlebrown",
                "Salmon",
                "Sandybrown",
                "Seagreen",
                "Seashell",
                "Sienna",
                "Silver",
                "Skyblue",
                "Slateblue",
                "Slategray",
                "Snow",
                "Springgreen",
                "Steelblue",
                "Tan",
                "Teal",
                "Thistle",
                "Tomato",
                "Turquoise",
                "Violet",
                "Wheat",
                "White",
                "Whitesmoke",
                "Yellow",
                "Yellowgreen"
            };
            str = regex.Replace(str, "$1");
            foreach (var temp in t)
            {
                regex = new Regex($@"\[{temp}\]((?:.|\n) +?)\[\/{temp}\]");
                str = regex.Replace(str, "$1");
            }

            return str;
        }

        private static string ConvertSize(string str)
        {
            var regex = new Regex(@"\[size\=.+?\]((?:.|\n)+?)\[\/size\]");
            return regex.Replace(str, "$1");
        }

        private static string ConvertQuote(string str)
        {
            var regex = new Regex(@"\[quote\=.+?\]((?:.|\n)+?)\[\/quote\]");
            return regex.Replace(str, "$1");
        }

        private static string ConvertCenter(string str)
        {
            var regex = new Regex(@"\[center\]((?:.|\n)+?)\[\/center\]");
            return regex.Replace(str, "$1");
        }

        private static string ConvertStrikethrough(string str)
        {
            var regex = new Regex(@"\[s\]((?:.|\n)+?)\[\/s\]");
            return regex.Replace(str, "~~$1~~");
        }

        private static string ConvertUnderline(string str)
        {
            Regex regex = new Regex(@"\[u\]((?:.|\n)+?)\[\/u\]");
            return regex.Replace(str, "$1");
        }

        private static string ConvertItalics(string str)
        {
            Regex regex = new Regex(@"\[i\]((?:.|\n)+?)\[\/i\]");
            return regex.Replace(str, "*$1*");
        }

        private static string ConvertBold(string str)
        {
            Regex regex = new Regex(@"\[b\]((?:.|\n)+?)\[\/b\]");
            return regex.Replace(str, "**$1**");
        }
    }