XmlElementJsonEncoder.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Xml;
using Waher.Content.Json;
using Waher.Runtime.Inventory;
 
namespace Waher.Content.Xml.Text
{
    public class XmlElementJsonEncoder : IJsonEncoder
    {
        public XmlElementJsonEncoder()
        {
        }
 
        public void Encode(object Object, int? Indent, StringBuilder Json)
        {
            XmlElement Xml = (XmlElement)Object;
            Encode(Xml, Indent, Json);
        }
 
        public static void Encode(XmlElement Xml, int? Indent, StringBuilder Json)
        {
            bool First = true;
 
            Json.Append('{');
 
            if (Indent.HasValue)
                Indent++;
 
            AppendProperty("__name", Xml.LocalName, Indent, ref First, Json);
            AppendProperty("__ns", Xml.NamespaceURI, Indent, ref First, Json);
 
            foreach (XmlAttribute Attr in Xml.Attributes)
                AppendProperty(Attr.Name, Attr.Value, Indent, ref First, Json);
 
            if (Xml.HasChildNodes)
            {
                Dictionary<string, LinkedList<XmlElement>> ChildElements = null;
                StringBuilder InnerText = null;
 
                foreach (XmlNode N in Xml.ChildNodes)
                {
                    if (N is XmlElement E)
                    {
                        if (ChildElements is null)
                            ChildElements = new Dictionary<string, LinkedList<XmlElement>>();
 
                        if (!ChildElements.TryGetValue(E.LocalName, out LinkedList<XmlElement> Elements))
                        {
                            Elements = new LinkedList<XmlElement>();
                            ChildElements[E.LocalName] = Elements;
                        }
 
                        Elements.AddLast(E);
                    }
                    else if (N is XmlText ||
                        N is XmlCDataSection ||
                        N is XmlWhitespace ||
                        N is XmlSignificantWhitespace)
                    {
                        if (InnerText is null)
                            InnerText = new StringBuilder();
 
                        InnerText.Append(N.InnerText);
                    }
                }
 
                if (!(ChildElements is null))
                {
                    foreach (KeyValuePair<string, LinkedList<XmlElement>> P in ChildElements)
                    {
                        if (P.Value.First.Next is null)
                            AppendProperty(P.Key, P.Value.First.Value, Indent, ref First, Json);
                        else
                            AppendProperty(P.Key, P.Value, Indent, ref First, Json);
                    }
 
                    if (!(InnerText is null))
                    {
                        AppendProperty(ChildElements.ContainsKey("value") ? "__value" : "value",
                            InnerText.ToString(), Indent, ref First, Json);
                    }
                }
                else if (!(InnerText is null))
                    AppendProperty("value", InnerText.ToString(), Indent, ref First, Json);
            }
 
            if (Indent.HasValue)
            {
                Indent--;
 
                if (!First)
                {
                    Json.AppendLine();
                    Json.Append(new string('\t', Indent.Value));
                }
            }
 
            Json.Append('}');
        }
 
        private static void AppendProperty(string Name, object Value, int? Indent, 
            ref bool First, StringBuilder Json)
        {
            if (First)
                First = false;
            else
                Json.Append(',');
 
            if (Indent.HasValue)
            {
                Json.AppendLine();
                Json.Append(new string('\t', Indent.Value));
            }
 
            Json.Append('"');
            Json.Append(JSON.Encode(Name));
            Json.Append("\":");
 
            if (Indent.HasValue)
                Json.Append(' ');
 
            JSON.Encode(Value, Indent, Json);
        }
 
        public Grade Supports(Type ObjectType)
        {
            return ObjectType == typeof(XmlElement) ? Grade.Ok : Grade.NotAtAll;
        }
 
    }
}