C# MongoDB 查询,分组,聚合,排序,条件,分页

先下载个C#的驱动。MongoDB提供各种主流与非主流预言的开发驱动。

C# Driver 下载地址：这里

CSharp Driver Tutorial：这里

下载文件安装或者解压缩包

如果您是安装，请到安装位置寻找，如果是ZIP压缩包，解压缩包得到如下两个文件：

MongoDB.Bson.dll              ：序列化、Json相关
MongoDB.Driver.dll             ：我们的驱动
没了，只有这两个文件是我们的最爱。



有帮助点推荐

using MongoDB.Driver;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using MySteel.Common.Helper;
using MongoDB.Driver.Builders;
using MongoDB.Bson.Serialization.Attributes;
using MongoDB.Bson;

namespace Test.MongoDB
{
class Program
{
/// <summary>
/// 数据库连接
/// </summary>
private const string conn = "mongodb://192.168.200.184:27017";
/// <summary>
/// 指定的数据库
/// </summary>
private const string dbName = "mlog";
/// <summary>
/// 指定的表
/// </summary>
private const string tbName = "log_table";
//创建数据连接
private static MongoServer server = MongoServer.Create(conn);
//获取指定数据库
private static MongoDatabase db = server.GetDatabase(dbName);

static void Main(string[] args)
{
//for (var index = 0; index < 2; index++)
//{
//    Student stu = new Student();
//    stu.Name = "name" + index;
//    stu.Age = index;
//    stu.CreateDateTime = DateTime.Now.ToMillisecond();
//    stu.Ques = new List<Ques>();
//    stu.Ques.Add(new Ques() { Name = "qname" + index });
//    Add(stu);
//}
Console.WriteLine("获取学生数据列表");
var list = GetStudentList();
foreach (var item in list)
{
Console.WriteLine(item.Name + " " + item.Age);
}
Console.WriteLine("获取学生姓名分组和数量");
Dictionary<string, int> group = GetStudentGroup();
foreach (var item in group)
{
Console.WriteLine(item.Key + " " + item.Value);
}
Console.Read();
}
/// <summary>
/// 添加
/// </summary>
/// <param name="text">内容</param>
/// <param name="articleId">文章ID</param>
/// <param name="channelId">频道ID</param>
/// <returns></returns>
public static void Add(Student t)
{
//获取表
MongoCollection col = db.GetCollection(tbName);
//插入
col.Insert(t);

}
public static List<Student> GetStudentList()
{
//创建数据连接
MongoServer server = MongoServer.Create(conn);
//获取指定数据库
MongoDatabase db = server.GetDatabase(dbName);
//获取表
MongoCollection<Student> col = db.GetCollection<Student>(tbName);
//条件查询
var query = Query.And(Query.LTE("Age", 5));
MongoCursor<Student> mongoCursor = col.FindAs<Student>(query);
//总数
Console.WriteLine(mongoCursor.Count());
mongoCursor = col.FindAs<Student>(query);
//排序
mongoCursor.SetSortOrder(SortBy.Descending("Age"));
//分页
mongoCursor.SetSkip(2);
mongoCursor.SetLimit(2);
List<Student> result = mongoCursor.ToList();
return result;
}
public static Dictionary<string, int> GetStudentGroup()
{
Dictionary<string, int> result = new Dictionary<string, int>();
result["num"] = 0;
//创建数据连接
MongoServer server = MongoServer.Create(conn);
//获取指定数据库
MongoDatabase db = server.GetDatabase(dbName);
//获取表
MongoCollection<Student> col = db.GetCollection<Student>(tbName);
GroupByBuilder groupbyBuilder = new GroupByBuilder(new string[] { "Name" });
var query = Query.And(Query.LTE("Age", 5));
var result_R = col.Group(query, groupbyBuilder, BsonDocument.Create(result), BsonJavaScript.Create("function(doc,prev){prev.num++;}"),
BsonJavaScript.Create("function(doc){ doc.count=doc.num;delete doc.num; }")).ToList();
if (result_R.Count != 0)
{
result = new Dictionary<string, int>();
for (int i = 1; i < result_R.Count; i++)
{
result.Add(result_R[i]["Name"].ToString(), Convert.ToInt32(result_R[i]["count"]));

}
}
return result;
}
}
[BsonIgnoreExtraElements]
public class Student
{
public string Name { get; set; }
public int Age { get; set; }
public List<Ques> Ques { get; set; }
public long CreateDateTime { get; set; }
}
[BsonIgnoreExtraElements]
public class Ques
{
public string Name { get; set; }
}
}