SwiftJSON

class Teacher: JSONModel {
	var name: String?
	var gender: Bool = false
	var classes: [String]?
	var age: Int=0
}

class Student: JSONModel {
	var name: String?
	var score: Double = 0
	var teacher: Teacher?
	
	override func toDict() -> JSONDict {
		var dict = super.toDict()
		write(&dict, key: "teacher", value: self.teacher)
		return dict
	}
}

var student:Student? = JSONUnmarshal("{\"name\":\"Tom\", \"score\":95, \"teacher\":{\"name\":\"Mr Li\", \"gender\":1, \"age\":36, \"classes\":[\"English\", \"Chinese\"]}}")

if let data = JSONMarshal(student!) {
	print(String(data: data, encoding: NSUTF8StringEncoding)!)
}

输出：

{
	"score" : 95,
	"teacher" : {
		"classes" : [
			"English",
			"Chinese"
		],
		"age" : 36,
		"gender" : true,
		"name" : "Mr Li"
	},
	"name" : "Tom"
}