C# formatting JSON as rtf document (can be useful to display on Richtext controls or exporting rtf files)

C# code that converts JSON string to RTF

sInJSON = sInJSON.Replace("\\", "\\\\").Replace("{", "\\{").Replace("}", "\\}").Replace(Environment.NewLine, "\\line" + Environment.NewLine);
string sRTFOut = @"{\rtf1\ansi\deff0
{\colortbl;\red0\green0\blue0;\red255\green140\blue0;\red255\green0\blue0;\red0\green128\blue0;\red0\green0\blue255;\red255\green0\blue255;\red0\green0\blue128;\red0\green128\blue128}" +
    Regex.Replace(
        sInJSON,
        @"(¤(\\u[a-zA-Z0-9]{4}|\\[^u]|[^\\¤])*¤(\s*:)?|\b(true|false|null)\b|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?)".Replace('¤', '"'),
        match =>
        {
            var cls = "\\cf2";
            if (Regex.IsMatch(match.Value, @"^¤".Replace('¤', '"')))
            {
                if (Regex.IsMatch(match.Value, ":$"))
                {
                    cls = "\\cf3";
                }
                else {
                    cls = "\\cf4";
                }
            }
            else if (Regex.IsMatch(match.Value, "true|false"))
            {
                cls = "\\cf5";
            }
            else if (Regex.IsMatch(match.Value, "null"))
            {
                cls = "\\cf6";
            }
            return cls + match + "\\cf1";
        })
+ "}";

Please review the RTF code outputted down below.

Points to Note: The RTF file always start with {\rtf1\ansi\deff0
After this, you can declare your color palatte as: {\colortbl;\red0\green0\blue0;\red255\green140\blue0;\red255\green0\blue0;\red0\green128\blue0;\red0\green0\blue255;\red255\green0\blue255;\red0\green0\blue128;\red0\green128\blue128}
and each of these can be later referred to as \cf1, \cf2 etc
Please also note that chars \, { and } are considered special characters. If you have it in your text, please override with \. For example, } should be changed as \} to display }

Example RTF code output:

{\rtf1\ansi\deff0
{\colortbl;\red0\green0\blue0;\red255\green140\blue0;\red255\green0\blue0;\red0\green128\blue0;\red0\green0\blue255;\red255\green0\blue255;\red0\green0\blue128;\red0\green128\blue128}\{\line
    \cf3"firstName":\cf1 \cf4"John"\cf1,\line
    \cf3"lastName":\cf1 \cf4"Smith"\cf1,\line
    \cf3"isAlive":\cf1 \cf5true\cf1,\line
    \cf3"age":\cf1 \cf225\cf1,\line
    \cf3"address":\cf1\line
    \{\line
        \cf3"streetAddress":\cf1 \cf4"21 2nd Street"\cf1,\line
        \cf3"city":\cf1 \cf4"New York"\cf1,\line
        \cf3"state":\cf1 \cf4"NY"\cf1,\line
        \cf3"postalCode":\cf1 \cf4"10021-3100"\cf1\line
    \},\line
    \cf3"phoneNumbers":\cf1\line
    [\line
        \{\line
            \cf3"type":\cf1 \cf4"home"\cf1,\line
            \cf3"number":\cf1 \cf4"212 555-1234"\cf1\line
        \},\line
        \{\line
            \cf3"type":\cf1 \cf4"office"\cf1,\line
            \cf3"number":\cf1 \cf4"646 555-4567"\cf1\line
        \}\line
    ],\line
    \cf3"children":\cf1\line
    [\line
    ],\line
    \cf3"spouse":\cf1 \cf6null\cf1\line
\}\line
}

Displayed as RTF:

{
   "firstName":"John",
   "lastName":"Smith",
   "isAlive":true,
   "age":,
   "address":
   {
       "streetAddress":"21 2nd Street",
       "city":"New York",
       "state":"NY",
       "postalCode":"10021-3100"
   },
   "phoneNumbers":
   [
       {
           "type":"home",
           "number":"212 555-1234"
       },
       {
           "type":"office",
           "number":"646 555-4567"
       }
   ],
   "children":
   [
   ],
 
You can also use this method to save/export to RTF files using your winform or ASP.Net web application