MongoDB 是一个基于分布式文件存储的数据库。由 C++ 语言编写。旨在为 WEB 应用提供可扩展的高性能数据存储解决方案。今天主要给大家介绍一下C#编程语言下Mongodb的用法。开发环境为VS2015示例主要包括数据的增删改查、分页查询、文件存储等功能。有需要的朋友可以一起学习一下。

1、需要引用Mongodb程序集

MongoDB.Bson.dll

MongoDB.Driver.dll

2、创建Mongodb工具类库 MongodbHelper.cs

using MongoDB.Bson;
using MongoDB.Driver;
using MongoDB.Driver.Builders;
using MongoDB.Driver.GridFS;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.Linq;namespace MongodbHelper
{/// <summary>/// MongoDB的基本增删改查/// </summary>public class MongodbTool{private readonly MongoDatabase _db;//数据库默认地址private readonly string host = ConfigurationManager.AppSettings["db_host"];//数据库默认名称private readonly string db_name = ConfigurationManager.AppSettings["db_name"];public MongodbTool(){var client = new MongoClient(host); //ip及端口var server = client.GetServer();_db = server.GetDatabase(db_name); //数据库名称}#region 通用增删改查/// <summary>/// 新增单个实体模型 modifiy by 2020-11-11/// </summary>/// <typeparam name="T"></typeparam>/// <param name="entity"></param>/// <returns>True:成功,False:失败</returns>public bool Insert<T>(T entity){bool isOk = true;try{BsonDocument doc = entity.ToBsonDocument();WriteConcernResult result = this._db.GetCollection(typeof(T).Name).Insert(doc);isOk = result.Ok;}catch (Exception ex){}return isOk;}/// <summary>/// 新增实体集合模型/// </summary>/// <typeparam name="T"></typeparam>/// <param name="entity"></param>/// <returns>True:成功,False:失败</returns>public bool Add<T>(IEnumerable<T> entity){bool isOk = true;try{int s = 1;IEnumerable<WriteConcernResult> results = this._db.GetCollection(typeof(T).Name).InsertBatch(entity);foreach (var item in results){if (item.Ok)isOk = true;elseisOk = false;}}catch (Exception ex){}return isOk;}/// <summary>/// 查询单条数据/// </summary>/// <typeparam name="T"></typeparam>/// <param name="Field">查询属性字段</param>/// <param name="Value">字段值</param>/// <returns>返回当前实体</returns>public T FindOne<T>(string Field, string Value){T oneEntity = default(T);try{FindOneArgs args = new FindOneArgs{Query = Query.EQ(Field, Value)};oneEntity = this._db.GetCollection(typeof(T).Name).FindOneAs<T>(args);this._db.GetCollection(typeof(T).Name).FindAs<T>(Query.GTE(Field, Value)).ToList();}catch (Exception ex){}return oneEntity;}/// <summary>/// 查询多条数据/// </summary>/// <typeparam name="T"></typeparam>/// <param name="Field">查询属性字段</param>/// <param name="Value">字段值</param>/// <returns>返回当前实体集合</returns>public List<T> FindMore<T>(string Field, string Value){List<T> list = new List<T>();try{list = this._db.GetCollection(typeof(T).Name).FindAs<T>(Query.GTE(Field, Value)).ToList();}catch (Exception ex){}return list;}/// <summary>/// 查询文档所有数据/// </summary>/// <typeparam name="T"></typeparam>/// <returns></returns>public List<T> FindAllMore<T>(){List<T> list = new List<T>();try{list = this._db.GetCollection(typeof(T).Name).FindAllAs<T>().ToList();}catch (Exception ex){}return list;}/// <summary>/// 分页查询文档/// </summary>/// <typeparam name="T"></typeparam>/// <param name="pageIndex">页次</param>/// <param name="pageRow">每页显示记录数</param>/// <param name="total">总记录数</param>/// <returns></returns>public List<T> FindMoreForPage<T>(int pageIndex, int pageRow, ref long total){List<T> list = new List<T>();try{total = this._db.GetCollection(typeof(T).Name).FindAllAs<T>().Count();    //获取总记录数if (pageIndex == 1){list = this._db.GetCollection(typeof(T).Name).FindAllAs<T>().SetLimit(pageRow).ToList();}else{var bd = this._db.GetCollection(typeof(T).Name).FindAll().SetSortOrder("_id:1").SetLimit((pageIndex - 1) * pageRow).Last();   //获取最后一个ID主键var el = bd.GetElement(0);var value = el.Value;list = this._db.GetCollection(typeof(T).Name).FindAs<T>(Query.GT("_id", value)).SetSortOrder("_id:1").SetLimit(pageRow).ToList();}}catch (Exception ex){}return list;}/// <summary>///  by 2020 ADD/// </summary>/// <typeparam name="T"></typeparam>/// <param name="query">查询条件</param>/// <param name="pageIndex">当前页</param>/// <param name="rows">行数</param>/// <param name="totalCount">总行数</param>/// <returns></returns>public List<T> FindPageNewAdd<T>(IMongoQuery query, int pageIndex, int rows, ref long totalCount){List<T> list = new List<T>();int skipCount = 0;try{if (pageIndex > 1){skipCount = (pageIndex - 1) * rows;}else{pageIndex = 1;}totalCount = this._db.GetCollection(typeof(T).Name).FindAs<T>(query).Count();if (totalCount > 0){list = this._db.GetCollection(typeof(T).Name).FindAs<T>(query).SetFlags(QueryFlags.NoCursorTimeout).SetSortOrder().SetSkip(skipCount).SetLimit(rows).ToList();}}catch (Exception){throw;}return list;}/// <summary>/// 按条件分页查询/// </summary>/// <typeparam name="T"></typeparam>/// <param name="query">查询条件</param>/// <param name="pageIndex">页次</param>/// <param name="pageRow">每页显示记录数</param>/// <param name="total">总记录数</param>/// <returns></returns>public List<T> FindMoreForPageByCondion<T>(IMongoQuery query, int pageIndex, int pageRow, ref long total){List<T> list = new List<T>();try{total = this._db.GetCollection(typeof(T).Name).FindAs<T>(query).Count();//获取总记录数if (pageIndex == 1){list = this._db.GetCollection(typeof(T).Name).FindAs<T>(query).SetSortOrder(SortBy.Descending("CreateDate")).SetLimit(pageRow).ToList();}else{var bd = this._db.GetCollection(typeof(T).Name).Find(query).SetSortOrder("_id:1").SetLimit((pageIndex - 1) * pageRow).Last();   //获取最后一个ID主键var el = bd.GetElement(0);var value = el.Value;list = this._db.GetCollection(typeof(T).Name).FindAs<T>(query).SetSortOrder("_id:1").SetSkip(pageRow).SetLimit(pageRow).ToList();}}catch (Exception ex){}return list;}/// <summary>/// 更新实体单个字段值/// </summary>/// <typeparam name="T"></typeparam>/// <param name="whereField">条件字段</param>/// <param name="whereValue">条件字段值</param>/// <param name="updateField">修改字段</param>/// <param name="updateValue">修改字段值</param>/// <returns></returns>public bool UpdateEntity<T>(string whereField, string whereValue, string updateField, string updateValue){bool isOk = true;try{var query = Query.EQ(whereField, whereValue);var update = Update.Set(updateField, updateValue);WriteConcernResult result = this._db.GetCollection(typeof(T).Name).Update(query, update);if (!result.Ok)isOk = false;}catch (Exception ex){}return isOk;}/// <summary>/// 更新整个实体模型字段/// </summary>/// <typeparam name="T">泛型参数</typeparam>/// <param name="whereField">条件字段</param>/// <param name="whereValue">条件值</param>/// <param name="updateEntity">实体模型</param>/// <returns>True:成功,False:失败</returns>public bool UpdateEntityMoreFields<T>(string whereField, string whereValue, T updateEntity){bool isOk = true;try{var query = Query.EQ(whereField, whereValue);BsonDocument bsonDoc = updateEntity.ToBsonDocument(typeof(T));var update = new UpdateDocument{{"$set",bsonDoc}};WriteConcernResult result = this._db.GetCollection(typeof(T).Name).Update(query, update);if (!result.Ok)isOk = false;}catch (Exception ex){}return isOk;}/// <summary>/// 删除实体文档/// </summary>/// <typeparam name="T">泛型参数</typeparam>/// <param name="whereField">条件字段</param>/// <param name="whereValue">条件值</param>/// <returns></returns>public bool DelEntity<T>(string whereField, string whereValue){bool isOk = true;try{var query = Query.EQ(whereField, whereValue);WriteConcernResult result = this._db.GetCollection(typeof(T).Name).Remove(query);if (!result.Ok)isOk = false;}catch (Exception ex){}return isOk;}#endregion#region GridFS 文件操作/// <summary>////// </summary>/// <returns></returns>public MongoCursor<MongoGridFSFileInfo> FindAll(){return this._db.GetGridFS(MongoGridFSSettings.Defaults).FindAll();}/// <summary>////// </summary>/// <param name="filePath"></param>public void UploadFile(string filePath){FileInfo fi = new FileInfo(filePath);this._db.GetGridFS(MongoGridFSSettings.Defaults).Upload(filePath, fi.Name);}/// <summary>////// </summary>/// <param name="filePath"></param>/// <param name="fileName"></param>public void UploadFile(string filePath, string fileName){this._db.GetGridFS(MongoGridFSSettings.Defaults).Upload(filePath, fileName);}/// <summary>///下载文件保存到默认目录/// </summary>/// <param name="fileName"></param>/// <param name="filePath"></param>public void DownloadFile(string fileName){this._db.GetGridFS(MongoGridFSSettings.Defaults).Download(fileName);}/// <summary>///下载文件保存到其他目录/// </summary>/// <param name="fileName"></param>/// <param name="filePath"></param>public void DownloadFileOther(string localFileName, string remoteFileName){this._db.GetGridFS(MongoGridFSSettings.Defaults).Download(localFileName,remoteFileName);}/// <summary>////// </summary>/// <param name="fileName"></param>public void DeleteFile(string fileName){this._db.GetGridFS(MongoGridFSSettings.Defaults).Delete(fileName);}/// <summary>////// </summary>public void DeleteAll(){foreach (var inst in this._db.GetGridFS(MongoGridFSSettings.Defaults).FindAll()){inst.Delete();}} #endregion}
}

3、创建实体 User.cs

using MongoDB.Bson;
namespace MongoHelper.Model
{public class User{public ObjectId _id;public string name { get; set; }public int age { get; set; }}
}

4、调用示例代码

var list = new List<User>();for (int i = 0; i < 100; i++){User user = new User();user.age = 20 + i;user.name = "测试" + i;list.Add(user);}//新增实体//tool.Add(list);//更新实体//tool.UpdateEntity<User>("name", "测试", "age", "99");//删除操作//tool.DelEntity<User>("name","测试");long total = 0;//构造查询条件IMongoQuery query = Query.And(Query.Matches("name", "1"));//分页查询数据var ll = tool.FindMoreForPageByCondion<User>(query, 0, 10, ref total);// 文件操作var model = tool.FindAllMore<User>();string folder = @"E:\photo";DirectoryInfo di = new DirectoryInfo(folder);//循环读取文件上传foreach (var file in di.GetFiles()){tool.UploadFile(file.FullName, file.Name);}var fileModel = tool.FindAll().First();// 保存文件指定目录tool.DownloadFileOther("D:\\"+fileModel.Name, fileModel.Name);//下载文件到当前目录pictureBox1.ImageLocation = "D:\\"+fileModel.Name;

具体的代码地址：https://gitee.com/hgm1989/mongodb-demo

如有问题可以随时沟通交流。

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