MongoDBHelper

using MongoDB.Driver;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks;

namespace KyeDePart.Common.BLL
{
    public class MongoDBHelper<T> where T : class
    {
        protected MongoClient mongoclient;
        protected IMongoDatabase database;
        protected IMongoCollection<T> collection;
        //public static MongoDBHelper<T> MongoDB=new MongoDBHelper<T>();

        /// <summary>
        /// 初始化操作
        /// </summary>
        public MongoDBHelper()
        {
            try
            {
                mongoclient = new MongoDB.Driver.MongoClient(ConfigurationSettings.AppSettings["MongoConnect"]);
                database = mongoclient.GetDatabase(ConfigurationSettings.AppSettings["MongoDatabase"]);
                collection = database.GetCollection<T>(typeof(T).Name);
            }
            catch (Exception ex)
            {
                Common.WriteLogFile(ex.ToString());
            }
        }

        /// <summary>
        /// MongoDB 语法
        /// </summary>
        /// <param name="filter"></param>
        /// <returns></returns>
        public T Query(FilterDefinition<T> filter)
        {
            return collection.Find(filter).FirstOrDefaultAsync().Result;
        }

        /// <summary>
        /// Linq 语法 
        /// </summary>
        /// <param name="func"></param>
        /// <returns></returns>
        public T Query(Expression<Func<T, bool>> func)
        {
            //collection.Find(func).ForEachAsync(x =>Console.WriteLine(""));
            return collection.Find(func).FirstOrDefaultAsync().Result;
        }

        public List<T> QueryList(FilterDefinition<T> filter)
        {
            //var s = collection.Find(filter).ForEachAsync(x => Console.WriteLine(""));
            return collection.Find(filter).ToListAsync().Result;
        }

        public List<T> QueryList(Expression<Func<T, bool>> func)
        {
            return collection.Find(func).ToListAsync().Result;
        }

        /// <summary>
        /// 分页查询
        /// Skip 性能不高
        /// </summary>
       
        /// <returns></returns>
        public List<T> QueryList(int PageIndex, int PageSize, Expression<Func<T, bool>> func, out long RecordCount)
        {
            RecordCount = collection.Find(func).Count();

            //方法一：
            return collection.AsQueryable<T>().Where(func).OrderByDescending(t => "_id").Skip(PageIndex * PageSize).Take(PageSize).ToList();

           

        }

        public bool IsExist(FilterDefinition<T> filter)
        {
            if (collection.Find(filter).FirstAsync().Result != null)
                return true;
            else
                return false;
        }
        public bool IsExist(Expression<Func<T, bool>> func)
        {
            if (collection.Find(func).FirstOrDefaultAsync().Result != null)
                return true;
            else
                return false;

            //long count = collection.CountAsync(func).Result;
            //if (count > 0)
            //    return true;
            //else
            //    return false;
        }

        public void Add(T model)
        {
            collection.InsertOneAsync(model);
        }

        public void Delete(Expression<Func<T, bool>> func)
        {
            collection.DeleteOneAsync(func);
        }

        public void Delete(FilterDefinition<T> filter)
        {
            collection.DeleteOneAsync(filter);
        }
        public void DeleteMany(Expression<Func<T, bool>> func)
        {
            collection.DeleteMany(func);
        }

        public void Update(FilterDefinition<T> filter, UpdateDefinition<T> updated)
        {
            collection.UpdateOneAsync(filter, updated);
        }
        public void UpdateMany(FilterDefinition<T> filter, UpdateDefinition<T> updated)
        {
            collection.UpdateManyAsync(filter, updated);
        }

        public void Update(Expression<Func<T, bool>> func, UpdateDefinition<T> updated)
        {
            collection.UpdateOneAsync(func, updated);
        }

        public void UpdateMany(Expression<Func<T, bool>> func, UpdateDefinition<T> updated)
        {
            collection.UpdateManyAsync(func, updated);
        }
    }
}

 public class PerSon
    {
        public ObjectId _id;
        public string Name { get; set; }
        public int Age { get; set; }
    }

public class PerSonBLL
    {
        protected static MongoDBHelper<Models.PerSon> mongoDB = new MongoDBHelper<Models.PerSon>();
        public static List<Models.PerSon> GetList()
        {
            return mongoDB.QueryList(t => t.Age > 10);
        }

    }