C#操作MongoDB数据库方法
本文利用MongoDB官方发布的C#驱动,封闭了对MongoDB数据库的增删改查访问方法。
1、引用MongoDB for C# Driver
从网上下载C#访问MongoDB的驱动,得到两个DLL:
- MongoDB.Driver.dll
- MongoDB.Bson.dll
将它们引用到项目中。
2、编写数据库访问帮助类
编写MongoDB访问帮助类MongoDbHelper:
1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using MongoDB.Bson; 5 using MongoDB.Driver; 6 using MongoDB.Driver.Builders; 7 using MongoDbTest.Models; 8 9 namespace MongoDbTest 10 { 11 /// <summary> 12 /// MongoDB帮助类 13 /// </summary> 14 internal static class MongoDbHepler 15 { 16 /// <summary> 17 /// 获取数据库实例对象 18 /// </summary> 19 /// <param name="connectionString">数据库连接串</param> 20 /// <param name="dbName">数据库名称</param> 21 /// <returns>数据库实例对象</returns> 22 private static MongoDatabase GetDatabase(string connectionString, string dbName) 23 { 24 var server = MongoServer.Create(connectionString); 25 return server.GetDatabase(dbName); 26 } 27 28 #region 新增 29 30 /// <summary> 31 /// 插入一条记录 32 /// </summary> 33 /// <typeparam name="T">数据类型</typeparam> 34 /// <param name="connectionString">数据库连接串</param> 35 /// <param name="dbName">数据名称</param> 36 /// <param name="collectionName">集合名称</param> 37 /// <param name="model">数据对象</param> 38 public static void Insert<T>(string connectionString, string dbName, string collectionName, T model) where T : EntityBase 39 { 40 if (model == null) 41 { 42 throw new ArgumentNullException("model", "待插入数据不能为空"); 43 } 44 var db = GetDatabase(connectionString, dbName); 45 var collection = db.GetCollection<T>(collectionName); 46 collection.Insert(model); 47 } 48 49 #endregion 50 51 #region 更新 52 53 /// <summary> 54 /// 更新数据 55 /// </summary> 56 /// <param name="connectionString">数据库连接串</param> 57 /// <param name="dbName">数据库名称</param> 58 /// <param name="collectionName">集合名称</param> 59 /// <param name="query">查询条件</param> 60 /// <param name="dictUpdate">更新字段</param> 61 public static void Update(string connectionString, string dbName, string collectionName, IMongoQuery query, Dictionary<string, BsonValue> dictUpdate) 62 { 63 var db = GetDatabase(connectionString, dbName); 64 var collection = db.GetCollection(collectionName); 65 var update = new UpdateBuilder(); 66 if (dictUpdate != null && dictUpdate.Count > 0) 67 { 68 foreach (var item in dictUpdate) 69 { 70 update.Set(item.Key, item.Value); 71 } 72 } 73 var d = collection.Update(query, update, UpdateFlags.Multi); 74 } 75 76 #endregion 77 78 #region 查询 79 80 /// <summary> 81 /// 根据ID获取数据对象 82 /// </summary> 83 /// <typeparam name="T">数据类型</typeparam> 84 /// <param name="connectionString">数据库连接串</param> 85 /// <param name="dbName">数据库名称</param> 86 /// <param name="collectionName">集合名称</param> 87 /// <param name="id">ID</param> 88 /// <returns>数据对象</returns> 89 public static T GetById<T>(string connectionString, string dbName, string collectionName, ObjectId id) 90 where T : EntityBase 91 { 92 var db = GetDatabase(connectionString, dbName); 93 var collection = db.GetCollection<T>(collectionName); 94 return collection.FindOneById(id); 95 } 96 97 /// <summary> 98 /// 根据查询条件获取一条数据 99 /// </summary> 100 /// <typeparam name="T">数据类型</typeparam> 101 /// <param name="connectionString">数据库连接串</param> 102 /// <param name="dbName">数据库名称</param> 103 /// <param name="collectionName">集合名称</param> 104 /// <param name="query">查询条件</param> 105 /// <returns>数据对象</returns> 106 public static T GetOneByCondition<T>(string connectionString, string dbName, string collectionName, IMongoQuery query) 107 where T : EntityBase 108 { 109 var db = GetDatabase(connectionString, dbName); 110 var collection = db.GetCollection<T>(collectionName); 111 return collection.FindOne(query); 112 } 113 114 /// <summary> 115 /// 根据查询条件获取多条数据 116 /// </summary> 117 /// <typeparam name="T">数据类型</typeparam> 118 /// <param name="connectionString">数据库连接串</param> 119 /// <param name="dbName">数据库名称</param> 120 /// <param name="collectionName">集合名称</param> 121 /// <param name="query">查询条件</param> 122 /// <returns>数据对象集合</returns> 123 public static List<T> GetManyByCondition<T>(string connectionString, string dbName, string collectionName, IMongoQuery query) 124 where T : EntityBase 125 { 126 var db = GetDatabase(connectionString, dbName); 127 var collection = db.GetCollection<T>(collectionName); 128 return collection.Find(query).ToList(); 129 } 130 131 /// <summary> 132 /// 根据集合中的所有数据 133 /// </summary> 134 /// <typeparam name="T">数据类型</typeparam> 135 /// <param name="connectionString">数据库连接串</param> 136 /// <param name="dbName">数据库名称</param> 137 /// <param name="collectionName">集合名称</param> 138 /// <returns>数据对象集合</returns> 139 public static List<T> GetAll<T>(string connectionString, string dbName, string collectionName) 140 where T : EntityBase 141 { 142 var db = GetDatabase(connectionString, dbName); 143 var collection = db.GetCollection<T>(collectionName); 144 return collection.FindAll().ToList(); 145 } 146 147 #endregion 148 149 #region 删除 150 151 /// <summary> 152 /// 删除集合中符合条件的数据 153 /// </summary> 154 /// <param name="connectionString">数据库连接串</param> 155 /// <param name="dbName">数据库名称</param> 156 /// <param name="collectionName">集合名称</param> 157 /// <param name="query">查询条件</param> 158 public static void DeleteByCondition(string connectionString, string dbName, string collectionName, IMongoQuery query) 159 { 160 var db = GetDatabase(connectionString, dbName); 161 var collection = db.GetCollection(collectionName); 162 collection.Remove(query); 163 } 164 165 /// <summary> 166 /// 删除集合中的所有数据 167 /// </summary> 168 /// <param name="connectionString">数据库连接串</param> 169 /// <param name="dbName">数据库名称</param> 170 /// <param name="collectionName">集合名称</param> 171 public static void DeleteAll(string connectionString, string dbName, string collectionName) 172 { 173 var db = GetDatabase(connectionString, dbName); 174 var collection = db.GetCollection(collectionName); 175 collection.RemoveAll(); 176 } 177 178 #endregion 179 180 } 181 }
3、编写测试类
(1)配置数据库参数
在配置文件中编写数据库连接串和数据库名称。
<?xml version="1.0" encoding="utf-8" ?> <configuration> <appSettings> <!--MongoDB数据库连接串--> <add key="MongoDBConn" value="mongodb://127.0.0.1:27017"/> <!--MongoDB数据库名称--> <add key="MongoDBName" value="mydb"/> </appSettings> <startup> <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" /> </startup> </configuration>
将其写入C#代码中:
using System.Configuration; namespace MongoDbTest { /// <summary> /// 数据库配置参数 /// </summary> internal static class DbConfigParams { private static string _conntionString = ConfigurationManager.AppSettings["MongoDBConn"]; /// <summary> /// 获取 数据库连接串 /// </summary> public static string ConntionString { get { return _conntionString; } } private static string _dbName = ConfigurationManager.AppSettings["MongoDBName"]; /// <summary> /// 获取 数据库名称 /// </summary> public static string DbName { get { return _dbName; } } } }
另外,将集合名称写到C#代码中作为字符串常量:
namespace MongoDbTest { public class CollectionNames { public const string User = "User"; public const string Student = "Student"; } }
(2)编写实体类
首先,编写实体基类,其中含有默认的Id:
using MongoDB.Bson; using MongoDB.Bson.Serialization.Attributes; namespace MongoDbTest.Models { /// <summary> /// 实体基类 /// </summary> public class EntityBase { /// <summary> /// 主键 /// </summary> [BsonId] public ObjectId Id { get; set; } } }
然后,编写实体类:
namespace MongoDbTest.Models { /// <summary> /// 学生类 /// </summary> public class Student : EntityBase { /// <summary> /// 获取 姓名 /// </summary> public string Name { get; set; } /// <summary> /// 获取 年龄 /// </summary> public int Age { get; set; } /// <summary> /// 获取 状态 /// </summary> public State State { get; set; } } }
其中,State枚举类定义如下:
namespace MongoDbTest.Models { /// <summary> /// 状态 /// </summary> public enum State { /// <summary> /// 全部 /// </summary> All = 0, /// <summary> /// 正常 /// </summary> Normal = 1, /// <summary> /// 未使用 /// </summary> Unused = 2, } }
(3)编写测试代码
在主程序中编写测试代码:
1 using System; 2 using System.Collections.Generic; 3 using MongoDB.Bson; 4 using MongoDB.Driver.Builders; 5 using MongoDbTest.Models; 6 7 namespace MongoDbTest 8 { 9 class Program 10 { 11 static void Main(string[] args) 12 { 13 Console.Title = "Mongo DB Test"; 14 InsertTest(); 15 //QueryTest(); 16 //UpdateTest(); 17 DeleteTest(); 18 19 Console.WriteLine("Finish!"); 20 21 Console.ReadLine(); 22 } 23 24 /// <summary> 25 /// 插入数据测试 26 /// </summary> 27 static void InsertTest() 28 { 29 var random = new Random(); 30 for (var i = 1; i <= 10; i++) 31 { 32 var item = new Student() 33 { 34 Name = "我的名字" + i, 35 Age = random.Next(25, 30), 36 State = i%2 == 0 ? State.Normal : State.Unused 37 }; 38 MongoDbHepler.Insert(DbConfigParams.ConntionString, DbConfigParams.DbName, CollectionNames.Student, item); 39 } 40 } 41 42 /// <summary> 43 /// 查询测试 44 /// </summary> 45 static void QueryTest() 46 { 47 var queryBuilder = new QueryBuilder<Student>(); 48 var query = queryBuilder.GTE(x => x.Age, 27); 49 var ltModel = MongoDbHepler.GetManyByCondition<Student>(DbConfigParams.ConntionString, DbConfigParams.DbName, 50 CollectionNames.Student, query); 51 if (ltModel != null && ltModel.Count > 0) 52 { 53 foreach (var item in ltModel) 54 { 55 Console.WriteLine("姓名:{0},年龄:{1},状态:{2}", 56 item.Name, item.Age, GetStateDesc(item.State)); 57 } 58 } 59 } 60 61 /// <summary> 62 /// 更新测试 63 /// </summary> 64 static void UpdateTest() 65 { 66 var queryBuilder = new QueryBuilder<Student>(); 67 var query = queryBuilder.GTE(x => x.Age, 27); 68 var dictUpdate = new Dictionary<string, BsonValue>(); 69 dictUpdate["State"] = State.Unused; 70 MongoDbHepler.Update(DbConfigParams.ConntionString, DbConfigParams.DbName, CollectionNames.Student, query, 71 dictUpdate); 72 } 73 74 /// <summary> 75 /// 删除测试 76 /// </summary> 77 static void DeleteTest() 78 { 79 var queryBuilder = new QueryBuilder<Student>(); 80 var query = queryBuilder.GTE(x => x.Age, 28); 81 MongoDbHepler.DeleteByCondition(DbConfigParams.ConntionString, DbConfigParams.DbName, CollectionNames.Student, query); 82 } 83 84 /// <summary> 85 /// 获取状态描述 86 /// </summary> 87 /// <param name="state">状态</param> 88 /// <returns>状态描述</returns> 89 static string GetStateDesc(State state) 90 { 91 string result = string.Empty; 92 switch (state) 93 { 94 case State.All: 95 result = "全部"; 96 break; 97 case State.Normal: 98 result = "正常"; 99 break; 100 case State.Unused: 101 result = "未使用"; 102 break; 103 default: 104 throw new ArgumentOutOfRangeException("state"); 105 } 106 return result; 107 } 108 } 109 }