.net 操作MongoDB 基础

1. 下载驱动，最好使用 NuGet 下载，直接搜索MongoDB；

2. 引用相关驱动

3. 部分测试代码，主要是针对MongoDB的GridFS 文件存储来用

using Mongo.Model;
using MongoDB.Bson;
using MongoDB.Driver;
using MongoDB.Driver.GridFS;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using System.Web;

namespace Mongo.Helper
{
    public static class MongoDBHelper
    {

        public static MongoClient client = new MongoClient("mongodb://localhost:27017");    
        public static IMongoDatabase db = client.GetDatabase("dzdaTest");//获取需要操作数据库
        public static void Add(Model.UserInfo user)
        {
            var collects = db.GetCollection<Model.UserInfo>("user");//获取需要操作的集合
            collects.InsertOne(user);
        }

        public static List<UserInfo> FindAll()
        {
            List<UserInfo> lis = new List<UserInfo>();
            var collects = db.GetCollection<UserInfo>("user");
            var filter = new BsonDocument();
            using(var cursor = collects.Find(filter).ToCursor())//查询结果转化为类似游标的类型
            {
                while (cursor.MoveNext())
                {
                    foreach (UserInfo item in cursor.Current)
                    {
                        lis.Add(item);
                    }
                }
            }
            return lis;
        }

        /// <summary>
        /// 上传图片
        /// </summary>
        /// <param name="name"></param>
        /// <param name="source"></param>
        /// <returns></returns>
        public static ObjectId UploadImg(string name, byte[] source)
        {
            var bucket = new GridFSBucket(db);//初始化GridFS
            return bucket.UploadFromBytes(name, source);
        }
        /// <summary>
        /// 上传图片
        /// </summary>
        /// <param name="name"></param>
        /// <param name="source"></param>
        /// <returns></returns>
        public static ObjectId UploadImg(string name, Stream source)
        {
            var bucket = new GridFSBucket(db);
            return bucket.UploadFromStream(name, source);
        }

        public async static Task<ObjectId> UploadImgAsync(string name, Stream source)
        {
            var bucket = new GridFSBucket(db);
            return await bucket.UploadFromStreamAsync(name, source);
        }
        /// <summary>
        /// 查询图片
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public static Stream FindImg(string id)
        {
            var bucket = new GridFSBucket(db);
            ObjectId objId=  new ObjectId(id);//通过ObjectId查询图片
            return bucket.OpenDownloadStream(objId);
        }

        /// <summary>
        /// 查询图片
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public static byte[] FindImgWithByte(string id)
        {
            var bucket = new GridFSBucket(db);
            ObjectId objId = new ObjectId(id);
            return bucket.DownloadAsBytes(objId);
        }
    }
}