Json 序列化

JavaScriptSerializer 是 .Net3.5 才加進來的類別， 可以用來將指定的 JSON 字串轉換成物件圖形。

public string Serialize(object obj);           
public object Deserialize(string input, Type targetType);
public T Deserialize<T>(string input);
public object DeserializeObject(string input);

• Serialize ：將物件或連接之物件的圖形序列化至指定資料流。
• Deserialize ：將資料流還原序列化至物件圖形。
• DeserializeObject ：將指定的 JSON 字串轉換成物件圖形。

Json 的序列化和還原序列化

private void btnJavaScriptSerializer_Click(object sender, EventArgs e)
{
    //initial data
    var employee = new Employee
    {
        ID = 1,
        Name = "vito",
        Birthday = new DateTime(1977, 7, 7),
        Departmnet = new Department
        {
            ID = 2,
            Name = "IT Dept"
        }
    };

    //Serialize an entity to Json

    JavaScriptSerializer jSer = new JavaScriptSerializer();
    string data = jSer.Serialize(employee);

    //Deserialize Json string to entity

    var emp = jSer.Deserialize<Employee>(data);

    Console.WriteLine("ID={0}", emp.ID);
    Console.WriteLine("Name={0}", emp.Name);
    Console.WriteLine("Birthday={0}", emp.Birthday.ToString());
    Console.WriteLine("DeptID={0}", emp.Departmnet.ID);
    Console.WriteLine("DeptName={0}", emp.Departmnet.Name);

    //ID=1
    //Name=vito
    //Birthday=1977/7/6 下午 04:00:00
    //DeptID=2
    //DeptName=IT Dept
}

public class Employee
{
    public int ID { get; set; }
    public string Name { get; set; }
    public DateTime Birthday { get; set; }
    public Department Departmnet { get; set; }
}
public class Department
{
    public int ID { get; set; }
    public string Name { get; set; }
}

底下是序列化後的資料內容

{"ID":1,"Name":"vito","Birthday":"/Date(237052800000)/","Departmnet":{"ID":2,"Name":"IT Dept"}}

註１：

JSON 格式的第一層不可以是陣列，否則無法還原序列化。

[
	{
		"empid":"1",
	    "name":"vito",
        "familys":[
            {"id":"001","name":"family1"},
            {"id":"002","name":"family2"},
            {"id":"003","name":"family3"}
        ]
    },
    {
        "empid":"2",
        "name":"shao",
        "familys":[{"id":"004","name":"family4"}]
    }
]

{
    "emps":
    [
        {
            "empid":"1",
            "name":"vito",
            "familys":[
                {"id":"001","name":"family1"},
                {"id":"002","name":"family2"},
                {"id":"003","name":"family3"}
            ]
        },
        {
            "empid":"2",
            "name":"shao",
            "familys":[
                {"id":"004","name":"family4"}
            ]
        }
    ]
}

註２：

在 .NET Framework 中，用來序列化 JSON 資料的類別，除了內建的 JavaScriptSerializer 外，還有 DataContractJsonSerializer 類別。 此外，還有免費的 Json.NET 類別可以使用。

將 Json 轉成 Dictionary

private void button2_Click(object sender, EventArgs e)
{
    string data = "{\"ID\":1,\"Name\":\"vito\",\"Birthday\":\"1977/7/7\",\"Departmnet\":{\"ID\":2,\"Name\":\"IT Dept\"}}";

    JavaScriptSerializer jSer = new JavaScriptSerializer();
    var obj = jSer.DeserializeObject(data);

    Dictionary<string, object> emp = jSer.DeserializeObject(data) as Dictionary<string, object>;
    Dictionary<string, object> dep = emp["Departmnet"] as Dictionary<string, object>;

    Console.WriteLine("ID={0}", emp["ID"].ToString());
    Console.WriteLine("Name={0}", emp["Name"].ToString());
    Console.WriteLine("Birthday={0}", emp["Birthday"].ToString());
    Console.WriteLine("DeptID={0}", dep["ID"].ToString());
    Console.WriteLine("DeptName={0}", dep["Name"].ToString());

    //ID=1
    //Name=vito
    //Birthday=1977/7/7
    //DeptID=2
    //DeptName=IT Dept
}

• C# 的 Json 序列化和反序列化(JSON.NET)