C＃-在JSON序列化和反序列化之间设置不同的PropertyName

问题描述

我正在查询API，响应是自定义JSON。浏览完网络后，我设法通过以下方式将其反序列化为自定义对象：

Post.cs

[JsonConverter(typeof(JsonPathConverter))]
public class Post
{
    [JsonProperty(PropertyName = "id")]
    public string Id { get; set; }

    [JsonProperty(PropertyName = "taken_at_timestamp")]
    public long Timestamp { get; set; }

    [JsonProperty(PropertyName = "edge_media_preview_like.count")]
    public int LikeCount { get; set; }

    [JsonProperty(PropertyName = "edge_media_to_comment.count")]
    public int CommentCount { get; set; }

    [JsonProperty(PropertyName = "edge_media_to_caption.edges[0].node.text")]
    public string Caption { get; set; }

    [JsonProperty(PropertyName = "display_url")]
    public string Image { get; set; }

    [JsonProperty(PropertyName = "dimensions.width")]
    public int Width { get; set; }

    [JsonProperty(PropertyName = "dimensions.height")]
    public int Height { get; set; }

    [JsonProperty(PropertyName = "shortcode")]
    public string Shortcode { get; set; }
}

JsonPathConverter.cs

public class JsonPathConverter : JsonConverter
{
    public override object ReadJson(JsonReader reader,Type objectType,object existingValue,JsonSerializer serializer)
    {
        JObject jo = JObject.Load(reader);
        object targetobj = Activator.CreateInstance(objectType);

        foreach (PropertyInfo prop in objectType.GetProperties().Where(p => p.CanRead && p.CanWrite))
        {
            JsonPropertyAttribute att = prop.GetCustomAttributes(true)
                                            .OfType<JsonPropertyAttribute>()
                                            .FirstOrDefault();

            string jsonPath = (att != null ? att.PropertyName : prop.Name);
            JToken token = jo.SelectToken(jsonPath);

            if (token != null && token.Type != JTokenType.Null)
            {
                object value = token.ToObject(prop.PropertyType,serializer);
                prop.SetValue(targetobj,value,null);
            }
        }

        return targetobj;
    }

    public override bool CanConvert(Type objectType)
    {
        return false;
    }

    public override bool CanWrite
    {
        get { return false; }
    }

    public override void WriteJson(JsonWriter writer,object value,JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }
}

问题是，当我想将该对象作为JSON发送时：它返回具有PropertyName值而不是属性名称的字段：

[
  {
    "id": "2322829435103312153","taken_at_timestamp": 1591122868,"edge_media_preview_like.count": 24,"edge_media_to_comment.count": 0,"edge_media_to_caption.edges[0].node.text": "...","display_url": "...","dimensions.width": 1080,"dimensions.height": 1080,"shortcode": "..."
  }
  ...
]

是否可以使用PropertyName进行反序列化，而使用属性名进行序列化？

更新

根据要求，这就是我使用反序列化和序列化的方式：

反序列化

JArray response = "[{ ... }]";

List<Post> posts = new List<Post>();

foreach (JObject node in response)
{
    Post post = JsonConvert.DeserializeObject<Post>(node.ToString());
    posts.Add(post);
}

序列化

我只是在“确定” IActionResult 中返回 List ：

Ok(posts);

解决方法

您可以使用ContractResolver，如下所示。

var jsondata = JsonConvert.SerializeObject(data,new JsonSerializerSettings { ContractResolver = new ShouldUseMemberNameContractResolver() });


public class ShouldUseMemberNameContractResolver : DefaultContractResolver
{
    public new static readonly ShouldUseMemberNameContractResolver Instance = new ShouldUseMemberNameContractResolver();

    protected override JsonProperty CreateProperty(MemberInfo member,MemberSerialization memberSerialization)
    {
        JsonProperty property = base.CreateProperty(member,memberSerialization);

        if (property.DeclaringType == typeof(Post))
        {
            property.PropertyName = member.Name;
        }

        return property;
    }
}

我按照Chetan Ranpariya的建议通过WriteJson方法解决了这个问题：

public override void WriteJson(JsonWriter writer,object value,JsonSerializer serializer)
{
    JArray result = new JArray();

    if (value.GetType().IsGenericType && value is IEnumerable)
    {
        IEnumerable list = value as IEnumerable;

        foreach(var obj in list)
        {
            result.Add(GetObjectJson(obj));
        }
    }

    result.WriteTo(writer);
}

private JObject GetObjectJson(object obj)
{
    JObject jObj = new JObject();
    PropertyInfo[] props = obj.GetType().GetProperties();

    foreach (PropertyInfo prop in props)
    {
        if (!prop.PropertyType.ToString().Contains("System"))
            jObj.Add(char.ToLowerInvariant(prop.Name[0]) + prop.Name.Substring(1),GetObjectJson(prop.GetValue(obj)));
        else
            jObj.Add(char.ToLowerInvariant(prop.Name[0]) + prop.Name.Substring(1),JToken.FromObject(prop.GetValue(obj)));
    }

    return jObj;
}

就像在object value参数中一样，我接收到对象（在这种情况下，它是一个列表），然后将其强制转换并对其对象进行迭代。

由于每个对象都可以具有原始属性和非原始属性，因此我创建了一个单独的函数以在发现嵌套对象的情况下递归使用它。

c#c#json json-deserialization