比较两个JSON文件并合并C#中的数据

Question

我有两个 JSONs 文件Country & Ceremony

国家 JSON：

[
 {
   "Short": "AF",
   "Name": "Afghanistan"
 },
 {
   "Short": "AN",
   "Name": "Netherlands Antilles"
 },
 {
   "Short": "AI",
   "Name": "Anguilla"
 },
 {
   "Short": "AL",
   "Name": "Albania"
 } ]

盛典JSON：

[
  {
    "CName": "Fitr",
    "CStart": "2021-11-10T09:00:00",
    "CEnd": "2021-11-14T09:00:00",
    "Loc": {
             "Info": "",
             "Short": "AF"
    }
  },
  {
    "CName": "Azha",
    "CStart": "2023-06-17T09:18:44",
    "CEnd": "2023-06-18T09:18:44",
    "Loc": {
             "Info": "",
              "Short": "AI"
    }
  },
  {
    "CName": "Azha",
    "CStart": "2022-01-05T00:00:00",
    "CEnd": "2022-01-05T23:59:59",
    "Loc": {
            "Info": "",
            "Short": "AL"
    }
  },
  {
     "CName": "Fitr",
     "CStart": "2022-01-05T00:00:00",
     "CEnd": "2022-01-05T23:59:59",
     "Loc": {
             "Info": "",
             "Short": "AN",
     }
  }  
  ]

国家 Model Class

public class Country
{
  public string Short{ get; set; }
  public string Name { get; set; }
}

盛典 Model Class

public class Ceremony
{
  public string CName { get; set; }
  public DateTime CStart { get; set; }
  public DateTime End { get; set; }
  public Loc loc { get; set; }
}

地点 Model Class

public class Loc
{
  public string Info { get; set; }
  public string Short { get; set; }
}

我想显示国家（名称）与 Ceremony、Loc 和 Short 的连接，这样当我在 Short 前面读取 Ceremony 数据时，我可以看到国家的全名。 国家全名应来自国家 JSON。

结果应该是这样的：

    CName CStart CEnd   Short        Name 
    Fitr  ""      ""    AF           Afghanistan
    Azha  ""      ""    AI           Anguilla

如何使用 LINQ 显示 2021 年仪式最多的国家，即使用 (Short)？

Answer 1

您可以像下面这样在ShortName上加入两个实体：

var countries = ...;
var ceremonies =  ...;

var result = (from c in countries
             join ce in ceremonies on c.Short equals ce.loc.Short
             select new {
              ce.CName,
              ce.CStart,
              ce.Cend,
              c.Short,
              c.Name
            }).Where(r=> r.CStart.Year == 2021).
            GroupBy(r=> r.Short).Select(r=> new { Short = r.Key, 
           EventCount = r.Count()}).OrderByDescending(r=> r.EventCount)
           .ToArray();
         

随着问题的发展，编辑添加了分组和排序。