MongoDB 工具助手类（.NET）

在开发过程中，需要用到MongoDB，本身MongoDB自己对类的封装就特别好了。为了更加符合我们平时的开发使用，我现在进行了一个简单的封装操作。

连接数据库类：MongoDBContext

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Configuration;



using MongoDB.Bson;

using MongoDB.Driver;

using MongoDB.Driver.Builders;

using MongoDB.Driver.Linq;



namespace XXXXX.MongoDB

{

    public class MongoDBContext

    {

        // 数据库链接

        private readonly MongoDatabase database;



        public MongoDBContext()

            : this(ConfigurationManager.AppSettings["DefaultMongoDBConnection"], ConfigurationManager.AppSettings["DefaultMonoDbDatabase"])

        {

        }



        /// <summary>

        /// 构造函数。根据指定连接字符串和数据库名

        /// </summary>

        /// <param name="connectionString">连接字符串</param>

        /// <param name="dbName">数据库名</param>

        public MongoDBContext(string connectionString, string dbName)

        {

            if (string.IsNullOrEmpty(connectionString))

            {

                throw new ArgumentNullException("connectionString is null");

            }



            if (string.IsNullOrEmpty(dbName))

            {

                throw new ArgumentNullException("dbName is null");

            }



            var client = new MongoClient(connectionString);

            var server = client.GetServer();

            this.database = server.GetDatabase(dbName);

        }



        /// <summary>

        /// 获取当前连接数据库的指定集合【依据类型】

        /// </summary>

        /// <typeparam name="T"></typeparam>

        /// <returns></returns>

        public MongoCollection<T> Collection<T>()

        {

            return database.GetCollection<T>(typeof(T).Name);

        }

    }

}

服务操作类：MongoDBService

using MongoDB.Driver.Builders;

using System;

using System.Collections.Generic;

using System.Linq;

using System.Linq.Expressions;

using System.Text;

using System.Threading.Tasks;



namespace XXXXX.MongoDB

{



    public class MongoDBService<T> : IMongoDBService<T> where T : class,new()

    {

        MongoDBContext mc = new MongoDBContext();



        /// <summary>

        /// 查询符合条件的集合

        /// </summary>

        /// <param name="whereLambda"></param>

        /// <returns></returns>

        public IEnumerable<T> GetList()

        {

            var query = Query<T>.Where(o => true);

            return mc.Collection<T>().Find(query);

        }



        /// <summary>

        /// 查询符合条件的集合

        /// </summary>

        /// <param name="whereLambda"></param>

        /// <returns></returns>

        public IEnumerable<T> GetList(Expression<Func<T, bool>> whereLambda)

        {

            var query = Query<T>.Where(whereLambda);

            return mc.Collection<T>().Find(query);

        }



        /// <summary>

        /// 查询一条记录

        /// </summary>

        /// <param name="whereLambda"></param>

        /// <returns></returns>

        public T GetOne(Expression<Func<T, bool>> whereLambda)

        {

            var query = GetList(whereLambda).FirstOrDefault();

            return query;

        }



        /// <summary>

        /// 增加

        /// </summary>

        /// <param name="entity"></param>

        public void Insert(T entity)

        {

            mc.Collection<T>().Insert(entity);

        }



        /// <summary>

        /// 批量增加

        /// </summary>

        /// <param name="entitys"></param>

        public void InsertAll(IEnumerable<T> entitys)

        {

            mc.Collection<T>().InsertBatch(entitys);

        }



        /// <summary>

        /// 更新一个实体

        /// </summary>

        /// <param name="entity"></param>

        public void Update(T entity)

        {

            mc.Collection<T>().Save(entity);

        }



        /// <summary>

        /// 删除

        /// </summary>

        /// <param name="whereLambda"></param>

        public void Remove(Expression<Func<T, bool>> whereLambda)

        {

            var query = Query<T>.Where(whereLambda);

            mc.Collection<T>().Remove(query);

        }

    }

}

上面方法封装完后，我们就可以直接使用了。使用很简单，比如，我有一个ActivityModel实体，使用时，如下：

        public void activityTest()

        {

            var activityDb = new MongoDBService<ActivityModel>();

            var activityList = activityDb.GetList().ToList();

            var activity = activityDb.GetOne(o => o.Id==ObjectId.Parse("54d9aecd89f0bd14d81a63a7"));

            var xxx = activity.To();

        }