Description

TinyJSON is a simple JSON library for C# that strives for ease of use.

Features

• Transmogrify objects into JSON and back again.
• Uses reflection to dump and load object graphs automagically.
• Supports primitives, classes, structs, enums, lists, dictionaries and arrays.
• Supports single dimensional arrays, multidimensional arrays and jagged arrays.
• Parsed data uses proxy variants that can be implicitly cast to primitive types for cleaner code.
• Numeric types are handled without fuss.
• Optional pretty printing JSON output.
• Polymorphic classes supported with a type hint encoded into the JSON.
• Optionally encode properties and private fields.
• Unit tested.

Usage

The API is namespaced under TinyJSON and the primary class is JSON. There are really only three methods you need to know:

namespace TinyJSON
{
	public static class JSON
	{
		public static Variant Load( string json );
		public static string Dump( object data, EncodeOptions = EncodeOptions.None );
		public static void MakeInto<T>( Variant data, out T item );
	}
}

Load() will load a string of JSON, returns null if invalid or a Variant proxy object if successful. The proxy allows for implicit casts and can convert between various C# numeric value types.

var data = JSON.Load( "{\"foo\": 1, \"bar\": 2.34}" );
int i = data["foo"];
float f = data["bar"];

Dump() will take a C# object, list, dictionary or primitive value type and turn it into JSON.

var data = new List<int>() { { 0 }, { 1 }, { 2 } };
Console.WriteLine( JSON.Dump( data ) ); // output: [1,2,3]

TinyJSON can also handle classes, structs, enums and nested objects. Given these definitions:

enum TestEnum
{
	Thing1,
	Thing2,
	Thing3
}


struct TestStruct
{
	public int x;
	public int y;
}


class TestClass
{
	public string name;
	public TestEnum type;
	public List<TestStruct> data = new List<TestStruct>();

	[Exclude]
	public int _ignored;

	[BeforeEncode]
	public void BeforeEncode()
	{
		Console.WriteLine( "BeforeEncode callback fired!" );
	}

	[AfterDecode]
	public void AfterDecode()
	{
		Console.WriteLine( "AfterDecode callback fired!" );
	}
}

The following code:

var testClass = new TestClass();
testClass.name = "Rumpelstiltskin Jones";
testClass.type = TestEnum.Thing2;
testClass.data.Add( new TestStruct() { x = 1, y = 2 } );
testClass.data.Add( new TestStruct() { x = 3, y = 4 } );
testClass.data.Add( new TestStruct() { x = 5, y = 6 } );

var testClassJson = JSON.Dump( testClass, true );
Console.WriteLine( testClassJson );

Will output:

{
	"name": "Rumpelstiltskin Jones",
	"type": "Thing2",
	"data": [
		{
			"x": 1,
			"y": 2
		},
		{
			"x": 3,
			"y": 4
		},
		{
			"x": 5,
			"y": 6
		}
	]
}

You can use, MakeInto() can be used to reconstruct JSON data back into an object:

TestClass testClass;
JSON.MakeInto( JSON.Load( testClassJson ), out testClass );

There are also Make() methods on Variant which provide options for slightly more natural syntax:

TestClass testClass;

JSON.Load( json ).Make( out testClass );
// or
testClass = JSON.Load( json ).Make<Data>();

Finally, you'll notice that TestClass has the methods BeforeEncode() and AfterDecode() which have the TinyJSON.BeforeEncode and TinyJSON.AfterDecode attributes. These methods will be called before the object starts being serialized and after the object has been fully deserialized. This is useful when some further preparation or initialization logic is required.

By default, only public fields are encoded, not properties or private fields. You can tag any field or property to be included with the TinyJSON.Include attribute, or force a public field to be excluded with the TinyJSON.Exclude attribute.

Type Hinting

When decoding polymorphic types, TinyJSON has no way of knowing which subclass to instantiate unless a type hint is included. So, by default, TinyJSON will add a key named @type to each encoded object with the fully qualified type of the object.

Encode Options

Two options are currently available for JSON encoding, and can be passed in as a second parameter to JSON.Dump().

• EncodeOptions.PrettyPrint will output nicely formatted JSON to make it more readable.
• EncodeOptions.NoTypeHints will disable the outputting of type hints into the JSON output. This may be desirable if you plan to read the JSON into another application that might choke on the type information. You can override this on a per-member basis with the TinyJSON.TypeHint attribute.

Using Variants

For most use cases you can just assign, cast or make your object graph using the API outlined above, but at times you may need to work with the intermediate proxy objects to, say, dig through and iterate over a collection. To do this, cast the variant to the appropriate subclass (either ProxyArray or ProxyObject) and you're good to go:

var list = JSON.Load( "[1,2,3]" );
foreach (var item in list as ProxyArray)
{
	int number = item;
	Console.WriteLine( number );
}

var dict = JSON.Load( "{\"x\":1,\"y\":2}" );
foreach (var pair in dict as ProxyObject)
{
	float value = pair.Value;
	Console.WriteLine( pair.Key + " = " + value );
}

Notes

This project was developed with pain elimination and lightweight size in mind. That said, it should be able able to handle reasonable amounts of reasonable data at reasonable speeds.

My primary use case for this library is with Mono and Unity3D (currently version 4), so compatibility is focused there, though it should work with most modern C# environments.

Meta

Handcrafted by Patrick Hogan [twitter • github • website]

Based on MiniJSON by Calvin Rien

Released under the MIT License.