Csharp C# JSON 反序列化为接口或字符串

写一个CustomConverter.在这里，我创建了一个可以与Hello1一起使用的自定义转换器，它只是省略了一些数据.如果改用Hello2类，则所有内容都包括在内.

public class Hello1Converter : Newtonsoft.Json.JsonConverter
{
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(Hello1);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var obj = value as IHello;
        writer.WriteValue(obj.Phrase);
    }
}

使用方法如下:

    [TestMethod]
    public void TestMethod1()
    {
        var greeting = new Greeting
        {
            Message = new Hello1
            {
                Phrase = "Yo!"
            }
        };

        var greeting2 = new Greeting
        {
            Message = new Hello2
            {
                Phrase = "Yo!"
            }
        };

        var jsonText1 = JsonConvert.SerializeObject(greeting, Formatting.Indented, new Hello1Converter());
        var jsonText2 = JsonConvert.SerializeObject(greeting2, Formatting.Indented, new Hello1Converter());
    }

jsonText1:

{
  "Message": "Yo!"
}

jsonText2:

{
  "Message": {
    "Phrase": "Yo!"
  }
}

请注意，这只处理序列化.对于反序列化，您还需要实现ReadJson.

以及您的课程:

public class Greeting
{
    public IHello Message { get; set; }
}

public interface IHello
{
    string Phrase { get; set; }
}

public class Hello1 : IHello
{
    public string Phrase { get; set; }
}

public class Hello2 : IHello
{
    public string Phrase { get; set; }
}