好的，正如official docs of Newtonsoft.Json中所描述的，首先为了良好的代码维护，我们应该创建一个模型，它将在C#类中描述所有（或仅域/业务逻辑需要）数据。

[JsonProperty("book")]
    public class Book
    {
        [JsonProperty("id")]
        public uint ID {get; set;} //GUID is better but, check how it's will be parsed 
        [JsonProperty("author")]
        public string Author {get; set;} // string can be replaced by Author model
        [JsonProperty("title")]
        public string Title {get; set;}
        [JsonProperty("genre")]
        public string Genre {get; set;} // string can be replaced by Enum
        [JsonProperty("price")]
        public double Price {get; set;}
        [JsonProperty("publish_date")]
        public string PublishDate {get; set;} // string can be replaced DateTime
        [JsonProperty("description")]
        public string Description {get; set;}
    }

目录模型

public class Catalog
    {
        [JsonProperty("book")]
       public List<Book> Book {get; set;} = new List<Book>();
    }

之后你可以做一些

string json = @"
{
  "catalog": {
    "book": [
      {
        "id": "1",
        "author": "Autho1",
        "title": "GDB",
        "genre": "Kl",
        "price": "15",
        "publish_date": "1999-09-02",
        "description": "desc about book"
      },
      {
        "id": "2",
        "author": "Lil",
        "title": "JS",
        "genre": "DS",
        "price": "3.6",
        "publish_date": "1999-09-02",
        "description": "desc 2."
      }    
    ]
  }
}";

Catalog catalog = JsonConvert.DeserializeObject<Catalog>(json);

如果需要对象和顺序（我记得仅此而已），则使用JsonProperty属性（不需要的地方）将默认解析器指定为json中的字段名。
我希望你的麻烦解决了，请下次多读些文件，在研究中要更有耐心。