[Fork] https://stackoverflow.com/questions/78402874/system-text-json-utf8jsonreader-is-reading-the-array-values-twice | C# Online Compiler

[Fork] https://stackoverflow.com/questions/78402874/system-text-json-utf8jsonreader-is-reading-the-array-values-twice by dbc_MinLength

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.Serialization.Formatters;
using System.IO;
using System.Data;
using System.ComponentModel.DataAnnotations;
using System.Globalization;
using System.Reflection;
using System.Collections.ObjectModel;

using System.Text.Json;
using System.Text.Json.Serialization;
using System.Text.Json.Serialization.Metadata;
using System.Text.Json.Nodes;

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

//#nullable enable

	// https://stackoverflow.com/questions/78402874/system-text-json-utf8jsonreader-is-reading-the-array-values-twice

    public class Map
    {
		// https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/immutability
		// Important: System.Text.Json requires that the constructor parameter names are the same as the corresponding property names, ignoring differences in case.
		[JsonConstructor]
		public Map(string mapname) => this.Mapname = mapname;
		public Map() : this("") { }
		
        [JsonPropertyName("Map name")]
        public string Mapname { get; }

        [JsonPropertyName("Entities")]
        public List<Entity> Entities { get; set; }

        [JsonPropertyName("Entity components")]
        public List<EntityComponent> Entitycomponents { get; set; }
    }

    public class ComponentDatum
    {
        [JsonPropertyName("Position")]
        public object Position { get; set; }

        [JsonPropertyName("Rotation")]
        public object Rotation { get; set; }

        [JsonPropertyName("Scale")]
        public object Scale { get; set; }

        [JsonPropertyName("Entity")]
        public string Entity { get; set; }

        [JsonPropertyName("GUIHeaderIsOpened")]
        public string GUIHeaderIsOpened { get; set; }

        [JsonPropertyName("Enabled")]
        public string Enabled { get; set; }

        [JsonPropertyName("GUID")]
        public string GUID { get; set; }
    }

    public class Entity
    {
        [JsonPropertyName("Name")]
        public string Name { get; set; }

        [JsonPropertyName("Active")]
        public string Active { get; set; }

        [JsonPropertyName("GUID")]
        public string GUID { get; set; }
    }

    public class EntityComponent
    {
        [JsonPropertyName("Component type")]
        public string Componenttype { get; set; }

        [JsonPropertyName("Component data")]
        public List<ComponentDatum> Componentdata { get; set; }
    }


#nullable enable

    class TestClass
    {
		static JsonSerializerOptions DefaultOptions { get; } = new() { AllowTrailingCommas = true, ReadCommentHandling = JsonCommentHandling.Skip };
		
		public Map? ReadYamlFromFile(string filePath)
		{
			using (var stream = File.OpenRead(filePath))
				return JsonSerializer.Deserialize<Map>(stream, DefaultOptions);
		}

		public Map? ReadYaml(string json)
		{
			JsonReaderOptions options = new() { AllowTrailingCommas = true, CommentHandling = JsonCommentHandling.Skip };
			Utf8JsonReader reader = new(System.Text.Encoding.UTF8.GetBytes(json), options);

			Map map = new();

			while (reader.Read())
			{
				switch (reader.TokenType)
				{
					case JsonTokenType.PropertyName:
						if (reader.ValueTextEquals("Map name"))
						{
							reader.Read();

							map = new(reader.GetString());
						}
						if (reader.ValueTextEquals("Entities"))
						{
							reader.Read();

							if (reader.TokenType == JsonTokenType.StartArray)
							{
								while (reader.Read())
								{
									if (reader.TokenType == JsonTokenType.EndArray)
										break;

									if (reader.TokenType == JsonTokenType.StartObject)
									{
										while (reader.Read())
										{
											if (reader.TokenType == JsonTokenType.EndObject)
												break;

											if (reader.TokenType == JsonTokenType.PropertyName)
											{
												reader.Read();
												if (reader.TokenType == JsonTokenType.String)
												{
													var str = reader.GetString();
													if (str != null)
													{
														Debug.Log(str);
													}
												}
											}
										}
									}
									else
									{
										break;
									}
								}
							}
						}
						break;
				}
			}
			return map;
		}
		
		public void Test()
		{
			TestFromString(GetJson());
		}
		
        public void TestFromString(string json)
        {
			var map = ReadYaml(json);

			//map.Dump();
			
			//Console.WriteLine("Deserialized and re-serialized {0}:", map);
			
			//var newJson = JsonSerializer.Serialize(map, new JsonSerializerOptions { WriteIndented = true });
			
			//Console.WriteLine(newJson);
			
			//Assert.That(JsonNode.DeepEquals(JsonNode.Parse(json), JsonNode.Parse(newJson)));
		}	
		
		static string GetJson() =>
			"""
			{
			  "Map name": "NewMap",
			  "Entities": [
				{
				  "Name": "Entity",
				  "Active": "True",
				  "GUID": "f06ed7d3-f1b3-4cfd-a623-a7ceb17dbced"
				},
				{
				  "Name": "Entity #1",
				  "Active": "True",
				  "GUID": "03788f46-e430-4882-a097-e860d2c7aed5"
				}
			  ],
			  "Entity components": [
				{
				  "Component type": "ExtremeEngine.Transform",
				  "Component data": [
					{
					  "Position": null,
					  "Rotation": null,
					  "Scale": null,
					  "Entity": "f06ed7d3-f1b3-4cfd-a623-a7ceb17dbced",
					  "GUIHeaderIsOpened": "True",
					  "Enabled": "True",
					  "GUID": "95dea154-6f00-41b0-bdec-fe78cca589c3"
					}
				  ]
				},
				{
				  "Component type": "ExtremeEngine.Transform",
				  "Component data": [
					{
					  "Position": null,
					  "Rotation": null,
					  "Scale": null,
					  "Entity": "03788f46-e430-4882-a097-e860d2c7aed5",
					  "GUIHeaderIsOpened": "True",
					  "Enabled": "True",
					  "GUID": "d92b131a-a82f-487f-b1c1-25ff13496284"
					}
				  ]
				}
			  ]
			}			
			""";
	}

	public class Program
	{
		public static void Main()
		{
			Console.WriteLine("Environment version: {0} ({1}), {2}", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion);
			Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);
			Console.WriteLine();

			try
			{
				new TestClass().Test();
			}
			catch (Exception ex)
			{
				Console.WriteLine("Failed with unhandled exception: ");
				Console.WriteLine(ex);
				throw;
			}
		}
	}

	public static class Debug
	{
		public static void Log(string s) => Console.WriteLine(s);
	}

​x
 
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.Serialization.Formatters;
using System.IO;
using System.Data;
using System.ComponentModel.DataAnnotations;
using System.Globalization;
using System.Reflection;
using System.Collections.ObjectModel;
​
using System.Text.Json;
using System.Text.Json.Serialization;
using System.Text.Json.Serialization.Metadata;
using System.Text.Json.Nodes;
​
using NUnit.Framework; // Throws NUnit.Framework.AssertionException
​
//#nullable enable
​
    // https://stackoverflow.com/questions/78402874/system-text-json-utf8jsonreader-is-reading-the-array-values-twice
​
    public class Map
    {
        // https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/immutability
        // Important: System.Text.Json requires that the constructor parameter names are the same as the corresponding property names, ignoring differences in case.
        [JsonConstructor]
        public Map(string mapname) => this.Mapname = mapname;
        public Map() : this("") { }
        
        [JsonPropertyName("Map name")]
        public string Mapname { get; }
​
        [JsonPropertyName("Entities")]
        public List<Entity> Entities { get; set; }
​
        [JsonPropertyName("Entity components")]
        public List<EntityComponent> Entitycomponents { get; set; }
    }
​
    public class ComponentDatum
    {
        [JsonPropertyName("Position")]
        public object Position { get; set; }
​
        [JsonPropertyName("Rotation")]
        public object Rotation { get; set; }
​
        [JsonPropertyName("Scale")]
        public object Scale { get; set; }
​
        [JsonPropertyName("Entity")]
        public string Entity { get; set; }
​
        [JsonPropertyName("GUIHeaderIsOpened")]
        public string GUIHeaderIsOpened { get; set; }
​
        [JsonPropertyName("Enabled")]
        public string Enabled { get; set; }
​
        [JsonPropertyName("GUID")]
        public string GUID { get; set; }
    }
​
    public class Entity
    {
        [JsonPropertyName("Name")]
        public string Name { get; set; }
​
        [JsonPropertyName("Active")]
        public string Active { get; set; }
​
        [JsonPropertyName("GUID")]
        public string GUID { get; set; }
    }
​
    public class EntityComponent
    {
        [JsonPropertyName("Component type")]
        public string Componenttype { get; set; }
​
        [JsonPropertyName("Component data")]
        public List<ComponentDatum> Componentdata { get; set; }
    }
​
​
#nullable enable
​
    class TestClass
    {
        static JsonSerializerOptions DefaultOptions { get; } = new() { AllowTrailingCommas = true, ReadCommentHandling = JsonCommentHandling.Skip };
        
        public Map? ReadYamlFromFile(string filePath)
        {
            using (var stream = File.OpenRead(filePath))
                return JsonSerializer.Deserialize<Map>(stream, DefaultOptions);
        }
​
        public Map? ReadYaml(string json)
        {
            JsonReaderOptions options = new() { AllowTrailingCommas = true, CommentHandling = JsonCommentHandling.Skip };
            Utf8JsonReader reader = new(System.Text.Encoding.UTF8.GetBytes(json), options);
​
            Map map = new();
​
            while (reader.Read())
            {
                switch (reader.TokenType)
                {
                    case JsonTokenType.PropertyName:
                        if (reader.ValueTextEquals("Map name"))
                        {
                            reader.Read();
​
                            map = new(reader.GetString());
                        }
                        if (reader.ValueTextEquals("Entities"))
                        {
                            reader.Read();
​
                            if (reader.TokenType == JsonTokenType.StartArray)
                            {
                                while (reader.Read())
                                {
                                    if (reader.TokenType == JsonTokenType.EndArray)
                                        break;
​
                                    if (reader.TokenType == JsonTokenType.StartObject)
                                    {
                                        while (reader.Read())
                                        {
                                            if (reader.TokenType == JsonTokenType.EndObject)
                                                break;
​
                                            if (reader.TokenType == JsonTokenType.PropertyName)
                                            {
                                                reader.Read();
                                                if (reader.TokenType == JsonTokenType.String)
                                                {
                                                    var str = reader.GetString();
                                                    if (str != null)
                                                    {
                                                        Debug.Log(str);
                                                    }
                                                }
                                            }
                                        }
                                    }
                                    else
                                    {
                                        break;
                                    }
                                }
                            }
                        }
                        break;
                }
            }
            return map;
        }
        
        public void Test()
        {
            TestFromString(GetJson());
        }
        
        public void TestFromString(string json)
        {
            var map = ReadYaml(json);
​
            //map.Dump();
            
            //Console.WriteLine("Deserialized and re-serialized {0}:", map);
            
            //var newJson = JsonSerializer.Serialize(map, new JsonSerializerOptions { WriteIndented = true });
            
            //Console.WriteLine(newJson);
            
            //Assert.That(JsonNode.DeepEquals(JsonNode.Parse(json), JsonNode.Parse(newJson)));
        }   
        
        static string GetJson() =>
            """
            {
              "Map name": "NewMap",
              "Entities": [
                {
                  "Name": "Entity",
                  "Active": "True",
                  "GUID": "f06ed7d3-f1b3-4cfd-a623-a7ceb17dbced"
                },
                {
                  "Name": "Entity #1",
                  "Active": "True",
                  "GUID": "03788f46-e430-4882-a097-e860d2c7aed5"
                }
              ],
              "Entity components": [
                {
                  "Component type": "ExtremeEngine.Transform",
                  "Component data": [
                    {
                      "Position": null,
                      "Rotation": null,
                      "Scale": null,
                      "Entity": "f06ed7d3-f1b3-4cfd-a623-a7ceb17dbced",
                      "GUIHeaderIsOpened": "True",
                      "Enabled": "True",
                      "GUID": "95dea154-6f00-41b0-bdec-fe78cca589c3"
                    }
                  ]
                },
                {
                  "Component type": "ExtremeEngine.Transform",
                  "Component data": [
                    {
                      "Position": null,
                      "Rotation": null,
                      "Scale": null,
                      "Entity": "03788f46-e430-4882-a097-e860d2c7aed5",
                      "GUIHeaderIsOpened": "True",
                      "Enabled": "True",
                      "GUID": "d92b131a-a82f-487f-b1c1-25ff13496284"
                    }
                  ]
                }
              ]
            }           
            """;
    }
​
    public class Program
    {
        public static void Main()
        {
            Console.WriteLine("Environment version: {0} ({1}), {2}", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion);
            Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);
            Console.WriteLine();
​
            try
            {
                new TestClass().Test();
            }
            catch (Exception ex)
            {
                Console.WriteLine("Failed with unhandled exception: ");
                Console.WriteLine(ex);
                throw;
            }
        }
    }
​
    public static class Debug
    {
        public static void Log(string s) => Console.WriteLine(s);
    }
​

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