LHZ.FastJson 2.0.1-pre

LHZ.FastJson

A lightweight and high-performance JSON serialization and deserialization library for .NET.

中文 | Changelog

Installation

The following examples show different installation methods using LHZ.FastJson 2.0.0 as an example:

Package Manager

Install-Package LHZ.FastJson -Version 2.0.0

.NET CLI

dotnet add package LHZ.FastJson --version 2.0.0

Package Reference

<PackageReference Include="LHZ.FastJson" Version="2.0.0" />

Paket CLI

paket add LHZ.FastJson --version 2.0.0

Usage

Serialization with LHZ.FastJson

Example

Student student = new Student
{
    NO = 1,
    [JsonProperty("studentName")]
    Name = "lhz",
    Age = 18,
    Brithday = new DateTime(2002, 1, 1)
};

string jsonStr = LHZ.FastJson.JsonConvert.Serialize(student);

Console.WriteLine(jsonStr);

Output

PS C:\Users\admin\source\repos\LHZ.FastJson\LHZ.FastJson.Test> dotnet run
{"NO":1,"studentName":"lhz","Age":18,"Brithday":"2000/1/1 0:00:00"}

Deserialization with LHZ.FastJson

Example

string str = "{\"NO\":1,\"studentName\":\"lhz\",\"Age\":18,\"Brithday\":\"2000/1/1 0:00:00\"}";

Student student = JsonConvert.Deserialize<Student>(str);

Console.WriteLine("NO:{0},Name:{1},Age:{2},Brithday:{3}", student.NO, student.Name, student.Age, student.Brithday.ToString("yyyy-MM-dd"));

Output

PS C:\Users\admin\source\repos\LHZ.FastJson\LHZ.FastJson.Test> dotnet run
NO:1,Name:lhz,Age:18,Brithday:2000-1-1

Camel-Case Configuration

By default, property names are serialized as-is (PascalCase). You can enable camelCase naming globally through JsonConvertConfig.UseCamelCase:

• During serialization, property names are converted to camelCase (e.g. UserName → userName);
• During deserialization, camelCase property names are matched automatically;
• Properties marked with the [JsonProperty("xxx")] attribute always keep the explicitly configured name;
• When the configuration changes, the compiled serialization/deserialization expression caches are invalidated automatically and recompiled.

Example

public class UserInfo
{
    public string UserName { get; set; }
    public int UserAge { get; set; }
}

JsonConvertConfig.UseCamelCase = true;

// Serialization: property names are converted to camelCase
string jsonStr = JsonConvert.Serialize(new UserInfo { UserName = "lhz", UserAge = 18 });
// Output: {"userName":"lhz","userAge":18}

// Deserialization: camelCase property names are matched automatically
UserInfo user = JsonConvert.Deserialize<UserInfo>("{\"userName\":\"lhz\",\"userAge\":18}");

JsonConvertConfig.UseCamelCase = false; // Restore the default

Building JSON Trees Programmatically

In addition to parsing JSON from strings, you can construct JSON trees directly using the JsonContent, JsonArray, JsonString, JsonNumber, JsonBoolean, and JsonNull classes:

//Object
var jsonContent = new JsonContent();
//Add String
jsonContent.AddJsonProperty("Name", new JsonString("LHZ.FastJson"));
//Add Number
jsonContent.AddJsonProperty("Size", new JsonNumber(1024));
//Add Boolean
jsonContent.AddJsonProperty("IsRelease", JsonBoolean.True);
//Add Null
jsonContent.AddJsonProperty("Exat", JsonNull.Null);
//Add Array
var jsonVersionArray = new JsonArray();
jsonVersionArray.AddJsonObject(new JsonString("2.0.0"));
jsonVersionArray.AddJsonObject(new JsonString("1.8.5"));
jsonVersionArray.AddJsonObject(new JsonString("1.8.4"));
jsonVersionArray.AddJsonObject(new JsonString("1.8.3"));
jsonContent.AddJsonProperty("Versions", jsonVersionArray);
//To Json String
var json = jsonContent.ToString();

OutPut

{"Name":"LHZ.FastJson","Size":1024,"IsRelease":true,"Exat":null,"Versions":["2.0.0","1.8.5","1.8.4","1.8.3"]}

JSON Parsing with JsonReader

JsonReader parses a JSON string into an IJsonObject tree that you can traverse dynamically.

Basic Parsing

using LHZ.FastJson;

string json = @"{""name"":""Alice"",""age"":25,""items"":[1,2,3]}";

var reader = new JsonReader(json);
IJsonObject obj = reader.JsonRead();

// Access parsed data
Console.WriteLine(obj["name"].Value);    // Alice
Console.WriteLine(obj["age"].Value);     // 25
Console.WriteLine(obj["items"][0].Value); // 1

Validate JSON

string json = @"{""key"":""value""}";

var reader = new JsonReader(json);
bool isValid = reader.IsValidJson;  // true

string invalidJson = @"{""key"":}";
var reader2 = new JsonReader(invalidJson);
bool isValid2 = reader2.IsValidJson; // false

Static Validation

bool isJson = JsonReader.IsJsonString(jsonString, out Exception exception);
if (!isJson)
{
    Console.WriteLine($"Invalid JSON: {exception.Message}");
}

Parsed JSON Type Tree

Serialization Performance

LHZ.FastJson has been re-architected with a highly optimized serialization engine. The table below compares serialization performance across LHZ.FastJson, Newtonsoft.Json, and System.Text.Json:

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.19044.1706 (21H2)
Intel Core i7-9700K CPU 3.60GHz (Coffee Lake), 1 CPU, 8 logical and 8 physical cores
.NET SDK=6.0.201
  [Host]     : .NET 6.0.3 (6.0.322.12309), X64 RyuJIT
  DefaultJob : .NET 6.0.3 (6.0.322.12309), X64 RyuJIT

Deserialization Performance

LHZ.FastJson has also been re-architected for deserialization, achieving nearly 2x performance improvement over versions prior to 1.6.0:

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.19044.1889 (21H2)
Intel Core i7-9700K CPU 3.60GHz (Coffee Lake), 1 CPU, 8 logical and 8 physical cores
.NET SDK=6.0.302
  [Host]     : .NET 6.0.7 (6.0.722.32202), X64 RyuJIT
  DefaultJob : .NET 6.0.7 (6.0.722.32202), X64 RyuJIT