MongoDB探索之路（二）——系统设计之CRUD

1.构造实体类

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;

 namespace EM.Model
 {
     public class News
     {
         public string _id { get; set; }
         public string title { get; set; }
         public string url { get; set; }
         public string author { get; set; }
         public int vote_count { get; set; }
         public List<string> tags { get; set; }
         public image image { get; set; }
         public List<comments> comments { get; set; }
         public DateTime createTime { get; set; }
         public DateTime updateTime { get; set; }
     }
     public class image
     {
         public string url { get; set; }
         public string caption { get; set; }
         public string type { get; set; }
         public string size { get; set; }
         public string data { get; set; }
     }
     public class comments
     {
         public int userId { get; set; }
         public string user { get; set; }
         public string text { get; set; }
         public DateTime createTime { get; set; }
         public DateTime updateTime { get; set; }
     }

 }

2.增加一条记录

             News news = new News();
             news._id = Guid.NewGuid().ToString();
             news.title = "大新闻";
             news.url = "http://www.cnblogs.com/cnki/";
             news.author = "沐风";
             news.vote_count = ;
             List<string> tagsList = new List<string>() { "国际", "编程", "dota" };
             news.tags = tagsList;
             image img = new image();
             img.url = "http://www.cnblogs.com/cnki/";
             img.caption = "好图";
             img.type = "回忆录";
             img.size = "3M";
             img.data = "dota三人组";
             news.image = img;

             List<comments> commentsList = new List<EM.Model.comments>();
             comments comment1 = new comments();
             comment1.userId = ;
             comment1.user = "三生石";
             comment1.text = "你所有的努力，只是为了更好的衬托别人的成功。";
             comment1.createTime = DateTime.Now;
             comment1.updateTime = DateTime.Now;
             commentsList.Add(comment1);

             comments comment2 = new comments();
             comment2.userId = ;
             comment2.user = "影魔";
             comment2.text = "明明可以靠脸吃饭，他却偏要靠才华，最后还是饿死了。";
             comment2.createTime = DateTime.Now;
             comment2.updateTime = DateTime.Now;
             commentsList.Add(comment2);

             news.comments = commentsList;

             news.createTime = DateTime.Now;
             news.updateTime = DateTime.Now;

             bool b = MongoDBServiceFactory.CreateMongoDBService(conStrNo, databaseName).Insert<News>("News", news);

存入MongoDB后的单条集合格式

{
    "_id" : "95565797-8572-4281-b6e6-6820d0c8dc37",
    "title" : "大新闻",
    "url" : "http://www.cnblogs.com/cnki/",
    "author" : "沐风",
    "vote_count" : ,
    "tags" : [
        "国际",
        "编程",
        "dota"
    ],
    "image" : {
        "url" : "http://www.cnblogs.com/cnki/",
        "caption" : "好图",
        "type" : "回忆录",
        "size" : "3M",
        "data" : "dota三人组"
    },
    "comments" : [
        {
            "userId" : ,
            "user" : "三生石",
            "text" : "你所有的努力，只是为了更好的衬托别人的成功。",
            "createTime" : ISODate("2016-12-05T13:40:46.142Z"),
            "updateTime" : ISODate("2016-12-05T13:40:46.142Z")
        },
        {
            "userId" : ,
            "user" : "影魔",
            "text" : "明明可以靠脸吃饭，他却偏要靠才华，最后还是饿死了。",
            "createTime" : ISODate("2016-12-05T13:40:46.142Z"),
            "updateTime" : ISODate("2016-12-05T13:40:46.142Z")
        }
    ],
    "createTime" : ISODate("2016-12-05T13:40:46.142Z"),
    "updateTime" : ISODate("2016-12-05T13:40:46.142Z")
}

增加一条评论

             comments commentsInfo = new comments();
             commentsInfo.userId = ;
             commentsInfo.user = "mf";
             commentsInfo.text = "世界太美好";
             commentsInfo.createTime = DateTime.Now;
             commentsInfo.updateTime = DateTime.Now;
             var update = Builders<News>.Update.Push(m => m.comments, commentsInfo);
             bool bUpdateOne = MongoDBServiceFactory.CreateMongoDBService(conStrNo, databaseName).UpdateOne<News>("News", m => m._id == "95565797-8572-4281-b6e6-6820d0c8dc37", update);

结果

 {
     "_id" : "95565797-8572-4281-b6e6-6820d0c8dc37",
     "title" : "大新闻",
     "url" : "http://www.cnblogs.com/cnki/",
     "author" : "沐风",
     "vote_count" : ,
     "tags" : [
         "国际",
         "编程",
         "dota"
     ],
     "image" : {
         "url" : "http://www.cnblogs.com/cnki/",
         "caption" : "好图",
         "type" : "回忆录",
         "size" : "3M",
         "data" : "dota三人组"
     },
     "comments" : [
         {
             "userId" : ,
             "user" : "三生石",
             "text" : "你所有的努力，只是为了更好的衬托别人的成功。",
             "createTime" : ISODate("2016-12-05T13:40:46.142Z"),
             "updateTime" : ISODate("2016-12-05T13:40:46.142Z")
         },
         {
             "userId" : ,
             "user" : "影魔",
             "text" : "明明可以靠脸吃饭，他却偏要靠才华，最后还是饿死了。",
             "createTime" : ISODate("2016-12-05T13:40:46.142Z"),
             "updateTime" : ISODate("2016-12-05T13:40:46.142Z")
         },
         {
             "userId" : ,
             "user" : "mf",
             "text" : "世界太美好",
             "createTime" : ISODate("2016-12-05T13:44:16.831Z"),
             "updateTime" : ISODate("2016-12-05T13:44:16.832Z")
         }
     ],
     "createTime" : ISODate("2016-12-05T13:40:46.142Z"),
     "updateTime" : ISODate("2016-12-05T13:40:46.142Z")
 }

3.查询一条记录

 News news = MongoDBServiceFactory.CreateMongoDBService(conStr, databaseName).Single<News>("News", m => m.author == "沐风");

4.更新一条记录

a.支持数增加1

 var updateDef = Builders<News>.Update.Inc(x => x.vote_count, 1);
 bool update = MongoDBServiceFactory.CreateMongoDBService(conStr, databaseName).UpdateOne<News>("News", x => x._id == "95565797-8572-4281-b6e6-6820d0c8dc37", updateDef);

b.修改Title字段

 var update = Builders<News>.Update.Set(m => m.title, "好大的新闻");
 bool updateResult = MongoDBServiceFactory.CreateMongoDBService(conStr, databaseName).UpdateOne("News", x => x._id == "95565797-8572-4281-b6e6-6820d0c8dc37", update);

c.根据userId更新一条子评论的comments字段

             //找到子文档
             var a = Builders<News>.Filter.Eq(x => x._id, "95565797-8572-4281-b6e6-6820d0c8dc37");
             var b = Builders<News>.Filter.ElemMatch(x => x.comments, y => y.userId == );
             var filter = Builders<News>.Filter.And(new FilterDefinition<News>[] { a, b });
             //更新子文档的字段
             var field = new StringFieldDefinition<News, string>("comments.$.comments");
             var update = Builders<News>.Update.Set(field, "修改后的我");
             //更新库
             UpdateResult updateResult = MongoDBServiceFactory.CreateMongoDBService(conStrNo, databaseName).DocumentUpdate("News", filter, update);
             bool bupdateResult= updateResult != null && updateResult.ModifiedCount >  && updateResult.ModifiedCount == updateResult.MatchedCount ? true : false;

5.删除

 bool delete = MongoDBServiceFactory.CreateMongoDBService(conStr, databaseName).Delete<News>("News", x => x._id == "95565797-8572-4281-b6e6-6820d0c8dc37") > 0;