c# - 使用 json.net 在序列化期间合并两个对象？

Question

我遇到了以下情况，有人可以帮我实现以下目标吗？

例如，如果我有课程：-

public class Sample
{
    public String name {get;set;}
    public MyClass myclass {get;set;}
}

我的Myclass意愿如下：

public class MyClass
{
    public String p1 {get;set;}
    public String p2 {get;set;}
}

当我Json.net用来序列化类 Sample 的对象时，我得到如下，它运行良好。

{
 "name":"...",
 "myclass":
          {
            "p1":"...",
            "p2":"..."
           }
 }

它是正确的，但我想知道是否有可能获得如下的 json 字符串？

{
 "name":"...",
 "p1":"...",
 "p2":"..."
}

Answer 1

您可以创建匿名对象并将其序列化：

var sample = new Sample { 
    name = "Bob", 
    myclass = new MyClass { 
                p1 = "x", 
                p2 = "y" 
              }};

string json = JsonConvert.SerializeObject(new { 
                 sample.name, 
                 sample.myclass.p1, 
                 sample.myclass.p2 
              });

结果

{"name":"Bob","p1":"x","p2":"y"}

但我建议您要么使用Sample类的默认序列化，要么创建将序列化为您的格式的类（即将MyClass属性移动到Sample.

更新：您可以使用自定义转换器，它将对象展平并将所有内部对象属性序列化为顶级对象属性：

public class FlattenJsonConverter : JsonConverter
{
    public override void WriteJson(JsonWriter writer, object value, 
        JsonSerializer serializer)
    {
        JToken t = JToken.FromObject(value);
        if (t.Type != JTokenType.Object)
        {
            t.WriteTo(writer);
            return;
        }

        JObject o = (JObject)t;
        writer.WriteStartObject();
        WriteJson(writer, o);
        writer.WriteEndObject();
    }

    private void WriteJson(JsonWriter writer, JObject value)
    {
        foreach (var p in value.Properties())
        {
            if (p.Value is JObject)
                WriteJson(writer, (JObject)p.Value);
            else
                p.WriteTo(writer);
        }
    }

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

    public override bool CanConvert(Type objectType)
    {
        return true; // works for any type
    }
}

用法：

string json = JsonConvert.SerializeObject(sample, new FlattenJsonConverter());

或者，如果您只需要一种类型的这种行为，您可以简单地将匿名类型创建隐藏到自定义转换器中：

public class SampleJsonConverter : JsonConverter
{
    public override void WriteJson(JsonWriter writer, 
        object value, JsonSerializer serializer)
    {
        Sample sample = (Sample)value;
        JToken t = JToken.FromObject(new { 
                      sample.name, 
                      sample.myclass.p1, 
                      sample.myclass.p2 
                   });

        t.WriteTo(writer);
    }

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

    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(Sample);
    }
}