c# - 对象中的 LINQ 分组

Question

我有两个类(class)

public class MyObjects{
  public bool Active {get; set;}
  public List<OtherObject> OtherObjects {get; set;}
}

public class OtherObject {
  public int Id {get; set;}
  public bool Enabled {get; set;}
  public string Address {get; set;}
  public string Name {get; set;}
}

我目前的结果是

MyObject { Active = true; }, 
OtherObjects: [OtherObject: { Id: 1, Name: 'First'}, 
OtherObject{Id: 2, Name: 'First'}, 
OtherObject{Id: 3, Name: 'Second'}];

我想按 Name 对它们进行分组，这样我仍然会有 Active 属性，而里面的那些 OtherObjects 将按 OtherObject 进行分组 名称 属性。是否可以只使用 LINQ 来做到这一点？

编辑:最终结果应该是 json，我将在角度中使用它，所以它应该是这样的:

{
  ""Active"": true,
  ""OtherObjects"": [
    {
      ""ObjectName"": ""Second"",
      ""ObjectOtherProperties"": [
        {
          ""Id"": 1,
          ""Enabled"": false
        },
        {
          ""Id"": 2,
          ""Enabled"": true
        }
      ],
      ""ObjectName"": ""Second"",
      ""ObjectOtherProperties"": [
        {
          ""Id"": 1,
          ""Enabled"": false
        }
      ],
    ]
  }
}

有什么建议可以实现吗？也许我必须创建其他类并以某种方式通过分组映射它们？

Answer 1

我会这样做，保持简单:

// 1. Add OtherObjectsDictionary
// 2. Block OtherObjects in the json serialization
public class MyObjects
{

    public bool Active { get; set; }

    [Newtonsoft.Json.JsonIgnore]
    public List<OtherObject> OtherObjects { get; set; }

    public Dictionary<string, List<OtherObject>> OtherObjectsDictionary { get; set; }

}

// 3. Block Name in the json serialization
public class OtherObject
{

    public int Id { get; set; }

    public bool Enabled { get; set; }

    public string Address { get; set; }

    [Newtonsoft.Json.JsonIgnore]
    public string Name { get; set; }

}

// 4. Linq queries to achieve the grouped result
// 5. Serialize to Json
static void Main(string[] args)
{

    var myObjects = new MyObjects() { Active = true, OtherObjects = new List<OtherObject>() };
    myObjects.OtherObjects.Add(new OtherObject { Id = 1, Name = "First" });
    myObjects.OtherObjects.Add(new OtherObject { Id = 2, Name = "First" });
    myObjects.OtherObjects.Add(new OtherObject { Id = 3, Name = "Second" });

    myObjects.OtherObjectsDictionary = new Dictionary<string, List<OtherObject>>();
    var distinctNames = myObjects.OtherObjects.Select(otherObject => otherObject.Name).Distinct();
    foreach(var distinctName in distinctNames)
    {
        var groupedObjectsList = myObjects.OtherObjects.Where(otherObject => otherObject.Name == distinctName).ToList();
        myObjects.OtherObjectsDictionary.Add(distinctName, groupedObjectsList);
    }

    var outputJson = Newtonsoft.Json.JsonConvert.SerializeObject(myObjects);

}   

这是 json 结果:

{
  "Active": true,
  "OtherObjectsDictionary": {
    "First": [
      {
        "Id": 1,
        "Enabled": false,
        "Address": null
      },
      {
        "Id": 2,
        "Enabled": false,
        "Address": null
      }
    ],
    "Second": [
      {
        "Id": 3,
        "Enabled": false,
        "Address": null
      }
    ]
  }
}

希望对你有所帮助。