迭代集合并创建嵌套对象

Question

我有一个模型，看起来像：

public class SearchResult
{
    public bool success { get; set; }
    public SearchData data { get; set; }
}
public class SearchData 
{
    public string UploadDate { get; set; }
    public List<UserImages> Images { get; set; }
}
public class UserImages
{
    public string Filename { get; set; }
    public string FileId { get; set; }
}

我的收集以以下格式返回结果

FileId  FileName    UploadDate
148847  IMG_1.JPG   Mar-2012
135710  IMG_8.JPG   Mar-2012
143817  IMG_6.JPG   Jul-2013
143873  IMG_5.JPG   Aug-2014
145766  IMG_4.JPG   Aug-2015
145820  IMG_3.JPG   Jan-2016
145952  IMG_2.JPG   Jan-2016

我想序列化上面的集合，这样我就可以生成以下JSON:

{
    "success": true,
    "SearchData": {
        "UploadDate": "MAR-2012",
        "UserImages": [{
            "Filename": "IMG_1.JPG",
            "FileId ": "148847"
        }, {
            "Filename": "IMG_8.JPG",
            "FileId ": "135710"
        }],
        "UploadDate": "Jul-2013",
        "UserImages": [{
            "Filename": "IMG_6.JPG",
            "FileId ": "143817"
        }]
    }
}

我就是无法让迭代工作。我如何迭代集合以创建模型类的对象，以便稍后对其进行序列化？

Answer 1

这将把您的集合变成对象模型，然后您可以将其序列化为JSON。

var result = new SearchResult
{
    Success = true,
    SearchData = results.GroupBy(item => item.UploadDate, 
               (key, grouping) => new SearchData 
               { 
                    UploadDate = key, 
                    Images = grouping.Select(item => new UserImage
                    {
                        FileName = item.FileName,
                        FileId = item.FileId 
                    }).ToList() 
               } ).ToList()
};
var json = new JavaScriptSerializer().Serialize(result);
var json_otherWay = Newtonsoft.Json.JsonConvert.SerializeObject(result);

请注意，SearchData是一个集合，而不是像上面代码中那样的单个项目：

public class SearchResult
{
    public bool Success { get; set; }
    public List<SearchData> Data { get; set; }
}

我从这里获得的JSON部分

Answer 2

这听起来像是一个经典的问题组。这里有一个自包含的示例，应该将粘贴编译复制到任何测试类中。

public class SearchResult
{
    public bool success { get; set; }
    public SearchData data { get; set; }
}
public class SearchData
{
    public string UploadDate { get; set; }
    public IEnumerable<UserImages> Images { get; set; }
}
public class UserImages
{
    public string Filename { get; set; }
    public string FileId { get; set; }
}
public class FlatData
{
    public string Id { get; set; }
    public string Name { get; set; }
    public DateTime Date { get; set; }
}
public static void Test()
{
    //generate arbitrary dates to group on
    var dates = Enumerable.Range(0, 3).Select(x => DateTime.Today.AddDays(x)).ToArray();
    //generate some sample data in the flat format
    var flatData = Enumerable.Range(1, 10).Select(x => new FlatData() { Id = x.ToString(), Name = "Image_" + x, Date = dates[x % 3] });
    //group the flat data into the hierarchical format
    var grouped = from item in flatData
                  group item by item.Date into g
                  select new SearchData()
                  {
                      UploadDate = g.Key.ToShortDateString(),
                      Images = from img in g
                               select new UserImages()
                               {
                                   FileId = img.Id,
                                   Filename = img.Name
                               }
                  };
    //Serialization implementation abstracted, as it should be
    var json = Common.Helper.SerializeJSON(grouped);
}}

json输出示例：

[
   {
      "UploadDate":"7/27/2016",
      "Images":[
         {
            "Filename":"Image_1",
            "FileId":"1"
         },
         {
            "Filename":"Image_4",
            "FileId":"4"
         },
         {
            "Filename":"Image_7",
            "FileId":"7"
         },
         {
            "Filename":"Image_10",
            "FileId":"10"
         }
      ]
   },
   {
      "UploadDate":"7/28/2016",
      "Images":[
         {
            "Filename":"Image_2",
            "FileId":"2"
         },
         {
            "Filename":"Image_5",
            "FileId":"5"
         },
         {
            "Filename":"Image_8",
            "FileId":"8"
         }
      ]
   },
   {
      "UploadDate":"7/26/2016",
      "Images":[
         {
            "Filename":"Image_3",
            "FileId":"3"
         },
         {
            "Filename":"Image_6",
            "FileId":"6"
         },
         {
            "Filename":"Image_9",
            "FileId":"9"
         }
      ]
   }
]

Answer 3

试试这个。

using Newtonsoft.Json;
public class SearchData 
{
    public string UploadDate { get; set; }
    public List<UserImages> Images { get; set; }
    public bool success { get; set; }
}
public class UserImages
{
    public string Filename { get; set; }
    public string FileId { get; set; }
}
var result= JsonConvert.DeserializeObject<List<SearchData>>("JsonString")