在C#中将通用集合转换为JSON

Question

在向集合中添加数据时，我遇到了一个情况。我需要将一些数据添加到集合中，然后按所需格式转换为json。

问题是，我没有得到我需要的json输出，只有字典集合给出我需要的输出，但是字典不允许其中存在重复的键，并且我需要添加重复数据。

我尝试过不同的集合，但无法获得所需的输出。

请查看以下代码片段并建议一个适当的解决方案。

//with distinct emails
var dict = new Dictionary<string, object>();
dict.Add("[e-mail]", new { id = 1, first = "FirstName", last = "LastName" });
dict.Add("[e-mail]", new { id = 2, first = "FirstName", last = "LastName" });
dict.Add("[e-mail]", new { id = 3, first = "FirstName", last = "LastName" });
dict.Add("[e-mail]", new { id = 4, first = "FirstName", last = "LastName" });
string dictJson = new JavaScriptSerializer().Serialize(dict);
//json result (requires output)
//{"[e-mail]":{"id":1,"first":"FirstName","last":"LastName"},"[e-mail]":{"id":2,"first":"FirstName","last":"LastName"},"[e-mail]":{"id":3,"first":"FirstName","last":"LastName"},"[e-mail]":{"id":4,"first":"FirstName","last":"LastName"}}

//Snippet - I: with duplicate emails
var list = new List<KeyValuePair<string, object>>();
list.Add(new KeyValuePair<string, object>("[e-mail]", new { id = 1, first = "FirstName", last = "LastName" }));
list.Add(new KeyValuePair<string, object>("[e-mail]", new { id = 2, first = "FirstName", last = "LastName" }));
list.Add(new KeyValuePair<string, object>("[e-mail]", new { id = 3, first = "FirstName", last = "LastName" }));
list.Add(new KeyValuePair<string, object>("[e-mail]", new { id = 4, first = "FirstName", last = "LastName" }));
string listJson = new JavaScriptSerializer().Serialize(list);
//json result
//[{"Key":"[e-mail]","Value":{"id":1,"first":"FirstName","last":"LastName"}},{"Key":"[e-mail]","Value":{"id":2,"first":"FirstName","last":"LastName"}},{"Key":"[e-mail]","Value":{"id":3,"first":"FirstName","last":"LastName"}},{"Key":"[e-mail]","Value":{"id":4,"first":"FirstName","last":"LastName"}}]

//Snippet - II: with duplicate emails
var tupleList = new List<Tuple<string, CustomClass>>();
tupleList.Add(Tuple.Create("[e-mail]", new CustomClass { id = 1, first = "FirstName", last = "LastName" }));
tupleList.Add(Tuple.Create("[e-mail]", new CustomClass { id = 2, first = "FirstName", last = "LastName" }));
tupleList.Add(Tuple.Create("[e-mail]", new CustomClass { id = 3, first = "FirstName", last = "LastName" }));
tupleList.Add(Tuple.Create("[e-mail]", new CustomClass { id = 4, first = "FirstName", last = "LastName" }));
string tupleListJson = new JavaScriptSerializer().Serialize(tupleList);
//json result
//[{"Item1":"[e-mail]","Item2":{"id":1,"first":"FirstName","last":"LastName"}},{"Item1":"[e-mail]","Item2":{"id":2,"first":"FirstName","last":"LastName"}},{"Item1":"[e-mail]","Item2":{"id":3,"first":"FirstName","last":"LastName"}},{"Item1":"[e-mail]","Item2":{"id":4,"first":"FirstName","last":"LastName"}}]

//Snippet - III: with duplicate emails
var genericList = new List<MainClass>();
genericList.Add(new MainClass { email = "[e-mail]", details = new CustomClass { id = 1, first = "FirstName", last = "LastName" } });
genericList.Add(new MainClass { email = "[e-mail]", details = new CustomClass { id = 2, first = "FirstName", last = "LastName" } });
genericList.Add(new MainClass { email = "[e-mail]", details = new CustomClass { id = 3, first = "FirstName", last = "LastName" } });
genericList.Add(new MainClass { email = "[e-mail]", details = new CustomClass { id = 4, first = "FirstName", last = "LastName" } });
string genericListJson = new JavaScriptSerializer().Serialize(genericList);
//json result
//[{"email":"[e-mail]","details":{"id":1,"first":"FirstName","last":"LastName"}},{"email":"[e-mail]","details":{"id":2,"first":"FirstName","last":"LastName"}},{"email":"[e-mail]","details":{"id":3,"first":"FirstName","last":"LastName"}},{"email":"[e-mail]","details":{"id":4,"first":"FirstName","last":"LastName"}}]

我不希望在JSON结果中出现键名。我只需要将“email”作为键，对象作为其值。 像这样：

{"[e-mail]":{"id":1,"first":"FirstName","last":"LastName"}}

- Abdul Mueed Shahid

---

尝试使用Newtonsoft库进行编程。链接 - Gaurav P

已经尝试过Newtonsoft库。 - Abdul Mueed Shahid

可能是将列表序列化为JSON的重复问题。 - Michael Freidgeim

Answer 1

首先，使用 List<KeyValuePair<string, object>>，因为需要允许重复。

var list = new List<KeyValuePair<string, object>>();
list.Add(new KeyValuePair<string, object>("foo", new { id = 1, first = "FirstName", last = "LastName" }));
list.Add(new KeyValuePair<string, object>("foo", new { id = 1, first = "FirstName", last = "LastName" }));
list.Add(new KeyValuePair<string, object>("foo", new { id = 1, first = "FirstName", last = "LastName" }));

使用JsonConvert进行序列化。

JsonSerializerSettings settings = new JsonSerializerSettings { Converters = new[] { new MyConverter() } };
string json = JsonConvert.SerializeObject(list, settings);

使用一个受这个答案启发的自定义转换器：

public class MyConverter : JsonConverter
{

    public override void WriteJson(JsonWriter writer, object value, Newtonsoft.Json.JsonSerializer serializer)
    {
        List<KeyValuePair<string, object>> list = value as List<KeyValuePair<string, object>>;
        writer.WriteStartArray();
        foreach (var item in list)
        {
            writer.WriteStartObject();
            writer.WritePropertyName(item.Key);
            // Needed because of the dynamic object.
            var jsonValue = JsonConvert.SerializeObject(item.Value);
            writer.WriteValue(jsonValue);
            writer.WriteEndObject();
        }
        writer.WriteEndArray();
    }

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

    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(List<KeyValuePair<string, object>>);
    }
}

输出：

[
    {"foo":"{\"id\":1,\"first\":\"FirstName\",\"last\":\"LastName\"}"},
    {"foo":"{\"id\":1,\"first\":\"FirstName\",\"last\":\"LastName\"}"},
    {"foo":"{\"id\":1,\"first\":\"FirstName\",\"last\":\"LastName\"}"}
]

- smoksnes

---

谢谢！现在我已经得到了我需要的输出。 - Abdul Mueed Shahid

Answer 2

为此，您需要将数据存储在字典列表中。这不是完美的解决方案，但您可以通过这种方式获得所需的输出。

class ValueHolder {
public string id { get; set; }
public string otherProp { get; set; }
}


var dic1 = new Dictionary<string, ValueHolder>();
dic1.Add("[e-mail]", new ValueHolder { id = "1", otherProp = "Lorem" });
dic1.Add("[e-mail]", new ValueHolder { id = "1", otherProp = "Lorem" });

var dic2 = new Dictionary<string, ValueHolder>();
dic2.Add("[e-mail]", new ValueHolder { id = "2", otherProp = "Lorem" });
dic2.Add("[e-mail]", new ValueHolder { id = "2", otherProp = "Lorem" });

var listOfDic = new List<Dictionary<string, ValueHolder>> { dic1, dic2 };
var result = JsonConvert.SerializeObject(listOfDic, Formatting.Indented);

[
  {
    "[e-mail]": {
      "id": "1",
      "otherProp": "lorem"
    },
    "[e-mail]": {
      "id": "1",
      "otherProp": "lorem"
    }
  },
  {
    "[e-mail]": {
      "id": "2",
      "otherProp": "lorem"
    },
    "[e-mail]": {
      "id": "2",
      "otherProp": "lorem"
    }
  }
]

- omer faruk