使用json仅序列化对象的一部分

时间:2011-02-14 23:38:08

标签: asp.net json

我有一个名为MyObject的对象,它有几个属性。 MyList是MyObject的列表,我用linq查询填充,然后将MyList序列化为json。我最终得到了类似的东西

    List<MyObject> MyList = new List<MyObject>();

    MyList = TheLinqQuery(TheParam);

    var TheJson = new System.Web.Script.Serialization.JavaScriptSerializer();
    string MyJson = TheJson.Serialize(MyList);

我想要做的只是序列化MyObject的部分内容。例如,我可能有Property1,Property2 ...... Propertyn,我希望MyJson只包含Property3,Property5和Property8。

我想到了一种方法,通过创建一个只包含我想要的属性的新对象,然后从那里创建一个新的序列化列表。这是最好的方式还是有更好/更快的方式?

感谢。

1 个答案:

答案 0 :(得分:3)

// simple dummy object just showing what "MyObject" could potentially be
public class MyObject
{
    public String Property1;
    public String Property2;
    public String Property3;
    public String Property4;
    public String Property5;
    public String Property6;
}

// custom converter that tells the serializer what to do when it sees one of
// the "MyObject" types. Use our custom method instead of reflection and just
// dumping properties.
public class MyObjectConverter : JavaScriptConverter
{
    public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
    {
        throw new ApplicationException("Serializable only");
    }

    public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
    {
        // create a variable we can push the serailized results to
        Dictionary<string, object> result = new Dictionary<string, object>();

        // grab the instance of the object
        MyObject myobj = obj as MyObject;
        if (myobj != null)
        {
            // only serailize the properties we want
            result.Add("Property1", myobj.Property1);
            result.Add("Property3", myobj.Property3);
            result.Add("Property5", myobj.Property5);
        }

        // return those results
        return result;
    }

    public override IEnumerable<Type> SupportedTypes
    {
        // let the serializer know we can accept your "MyObject" type.
        get { return new Type[] { typeof(MyObject) }; }
    }
}

然后你在哪里序列化:

// create an instance of the serializer
JavaScriptSerializer serializer = new JavaScriptSerializer();
// register our new converter so the serializer knows how to handle our custom object
serializer.RegisterConverters(new JavaScriptConverter[] { new MyObjectConverter() });
// and get the results
String result = serializer.Serialize(MyObjectInstance);