JSON中的动态键

首先，我不确定“动态键”是否正确，但我的问题是以下问题。

当前json：

{
  "Entered": "2012-08-18T13:26:37.7137482-10:00",
  "AlbumName": "Dirty Deeds Done Dirt Cheap",
  "Artist": "AC/DC",
  "YearReleased": 1976,
  "Songs": [
    {
      "SongName": "Dirty Deeds Done Dirt Cheap",
      "SongLength": "4:11"
    },
    {
      "SongName": "Love at First Feel",
      "SongLength": "3:10"
    }
  ]
}

新的那一个：

{
  "Entered": "2012-08-18T13:26:37.7137482-10:00",
  "AlbumName": "Dirty Deeds Done Dirt Cheap",
  "Artist": "AC/DC",
  "YearReleased": 1976,
  "Songs": {
    "Dirty Deeds Done Dirt Cheap": {
                                    "SongLength": "4:11"
                                   },
    "Love at First Feel": {
                           "SongLength": "3:10"
                          }
  }
}

我的问题是模型应如何显示，如何动态更改键名？

public class CD
    {
        public DateTime Entered { get; set; }
        public string AlbumName { get; set; }
        public string Artist { get; set; }
        public int YearReleased { get; set; }
        public List<Song> Songs { get; set; }
    }
public class Song
    {
        public string Name {get;set;}
        public string Length {get;set;}
    }