JsonFormatter.cs

/*
 * 
 * This class was written by Ralph (http://stackoverflow.com/users/65387/ralph) and retrieved from http://stackoverflow.com/questions/4580397/json-formatter-in-c
 * 
 * It is used only as a library in the HTTP Requester
 * 
 */


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace HTTPRequest
{

    public class JsonFormatter
    {
        #region class members
        const string Space = " ";
        const int DefaultIndent = 0;
        const string Indent = Space + Space + Space + Space;
        static readonly string NewLine = Environment.NewLine;
        #endregion

        private enum JsonContextType
        {
            Object, Array
        }

        static void BuildIndents(int indents, StringBuilder output)
        {
            indents += DefaultIndent;
            for (; indents > 0; indents--)
                output.Append(Indent);
        }


        bool inDoubleString = false;
        bool inSingleString = false;
        bool inVariableAssignment = false;
        char prevChar = '\0';

        Stack<JsonContextType> context = new Stack<JsonContextType>();

        bool InString()
        {
            return inDoubleString || inSingleString;
        }

        public string PrettyPrint(string input)
        {
            var output = new StringBuilder(input.Length * 2);
            char c;

            for (int i = 0; i < input.Length; i++)
            {
                c = input[i];

                switch (c)
                {
                    case '{':
                        if (!InString())
                        {
                            if (inVariableAssignment || (context.Count > 0 && context.Peek() != JsonContextType.Array))
                            {
                                output.Append(NewLine);
                                BuildIndents(context.Count, output);
                            }
                            output.Append(c);
                            context.Push(JsonContextType.Object);
                            output.Append(NewLine);
                            BuildIndents(context.Count, output);
                        }
                        else
                            output.Append(c);

                        break;

                    case '}':
                        if (!InString())
                        {
                            output.Append(NewLine);
                            context.Pop();
                            BuildIndents(context.Count, output);
                            output.Append(c);
                        }
                        else
                            output.Append(c);

                        break;

                    case '[':
                        output.Append(c);

                        if (!InString())
                            context.Push(JsonContextType.Array);

                        break;

                    case ']':
                        if (!InString())
                        {
                            output.Append(c);
                            context.Pop();
                        }
                        else
                            output.Append(c);

                        break;

                    case '=':
                        output.Append(c);
                        break;

                    case ',':
                        output.Append(c);

                        if (!InString() && context.Peek() != JsonContextType.Array)
                        {
                            BuildIndents(context.Count, output);
                            output.Append(NewLine);
                            BuildIndents(context.Count, output);
                            inVariableAssignment = false;
                        }

                        break;

                    case '\'':
                        if (!inDoubleString && prevChar != '\\')
                            inSingleString = !inSingleString;

                        output.Append(c);
                        break;

                    case ':':
                        if (!InString())
                        {
                            inVariableAssignment = true;
                            output.Append(Space);
                            output.Append(c);
                            output.Append(Space);
                        }
                        else
                            output.Append(c);

                        break;

                    case '"':
                        if (!inSingleString && prevChar != '\\')
                            inDoubleString = !inDoubleString;

                        output.Append(c);
                        break;
                    case ' ':
                        if (InString())
                            output.Append(c);
                        break;

                    default:
                        output.Append(c);
                        break;
                }
                prevChar = c;
            }

            return output.ToString();
        }
    }

}