记一次Mongodb数据库更新操作之更新为数组或者对象

　　一直以来都是更新为一些简单的基础类型，直到有一天写了一个覆盖某一个字段（这个字段为数组）的更新操作。出问题了，数据库中出现了_t,_v……有点懵了。当然如果我们更新的时候设置类型是不会出现这个问题的，出现这种问题的一个前提是我们将数组赋值给了object类型的变量；由于时间关系问了一下同事，她给出了解决办法：mongodb的驱动去反序列化一下。问题就这么解决了，今天有时间记录一下，在写示例代码的时候发现更新对象也不行。

　　先看一下我们的数据，以及更新之后的截图：

/* 1 */
{
    "_id" : "1",
    "Name" : "ddz001",
    "Age" : 10,
    "Valid" : true,
    "CreateDate" : ISODate("2020-03-28T05:59:43.841Z"),
    "LastUpdatedTime" : ISODate("2020-03-28T05:59:43.841Z"),
    "Details" : {
        "Height" : 169.5,
        "Weight" : 70.5,
        "Married" : true
    },
    "Bookmarks" : [ 
        {
            "Title" : "百度一下",
            "Url" : "https://www.baidu.com/"
        }, 
        {
            "Title" : "必应",
            "Url" : "https://cn.bing.com/"
        }
    ]
}

/* 2 */
{
    "_id" : "2",
    "Name" : "ddz002",
    "Age" : 20,
    "Valid" : true,
    "CreateDate" : ISODate("2020-03-28T05:59:43.841Z"),
    "LastUpdatedTime" : ISODate("2020-03-28T05:59:43.841Z"),
    "Details" : {
        "Height" : 170.5,
        "Weight" : 71.5,
        "Married" : true
    },
    "Bookmarks" : [ 
        {
            "Title" : "搜狗搜索",
            "Url" : "https://www.baidu.com/"
        }, 
        {
            "Title" : "多吉搜索",
            "Url" : "https://www.dogedoge.com/"
        }
    ]
}

　　为什么会出现上图中的问题，打印了一下UpdateDefinition生成的shell命令，你会发现是这样的，

　　后面直接用同事的方法试了一下，再查看生成的语句就没问题了

　　既然UpdateDefinition可以转成字符串，并且他同样可以直接赋值为字符串，例如：UpdateDefinition updateDefinition = ""; ，那么我想了一下我们直接拼这个字符串应该就没问题了，当然这种我没有测试啊！

　　这里面还会遇到一个问题就是怎么判断一个object的真实类型，这里仅仅需要知道他是不是对象或者数组（这里是泛指所有的）。可能真的有点菜，不知道如果判断。看了一下官方文档：Type类，也没有找到，最后还是使用比较笨的方法：先序列化为字符串之后在反序列化为object，他会告诉你类型的。最后一个问题是这个解决问题的办法是不是最优的，感觉有点浪费……如果有哪位大神知道高效的方式，请不吝赐教，再次感谢。

　　最后看一下我的示例代码：

using MongoDB.Bson;
using MongoDB.Bson.Serialization;
using MongoDB.Bson.Serialization.Attributes;
using MongoDB.Driver;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Encodings.Web;
using System.Text.Json;

namespace DDZ.MongodbUpdateArrayTest
{
    class Program
    {
        static void Main(string[] args)
        {
            //清空表（新增之前先清空）、批量添加（初始化一些数据）、查询操作
            //DeleteManyBatchAddFind();

            //更新数据和Object测试
            //UpdateArrayOrObject();

            #region 寻找解决办法
            var _client = new MongoClient("mongodb://localhost:27017");
            var _database = _client.GetDatabase("FormBuilder");
            var _collection = _database.GetCollection("UpdateArrayTest");
            DateTime dtNow2 = DateTime.Now;
            List keyValueModels = new List()
            {
                new KeyValueModel(){ Key="Name",Value ="ddz001+++" },
                new KeyValueModel(){ Key="Age",Value = 11 },
                new KeyValueModel(){ Key="Valid",Value = false },
                new KeyValueModel(){ Key="LastUpdatedTime",Value=dtNow2 },
                new KeyValueModel(){ Key="Details",Value = new OtherInfoModel(){ Height=179.5f,Weight=80.5f,Married=false } },
                new KeyValueModel()
                {
                    Key="Bookmarks",Value = new List()
                    {
                        new BookmarkModel() { Title="Yandex",Url="https://yandex.com/" },
                        new BookmarkModel() { Title="秘迹搜索",Url="https://mijisou.com/" }
                    }
                }
            };
            var tempUpdateObj = new
            {
                Name = "ddz001+++",
                Age = 11,
                Valid = false,
                LastUpdatedTime = dtNow2,
                Details = new OtherInfoModel() { Height = 179.5f, Weight = 80.5f, Married = false },
                Bookmarks = new List()
                    {
                        new BookmarkModel() { Title="Yandex",Url="https://yandex.com/" },
                        new BookmarkModel() { Title="秘迹搜索",Url="https://mijisou.com/" }
                    }
            };
            var tempUpdateDic = new Dictionary<string, object>() 
            {
                { "Name", "ddz001+++"},
                { "Age", ""},
                { "Valid", false},
                { "LastUpdatedTime", dtNow2},
                { "Details", new OtherInfoModel() { Height = 179.5f, Weight = 80.5f, Married = false }},
                { "Bookmarks", new List()
                    {
                        new BookmarkModel() { Title="Yandex",Url="https://yandex.com/" },
                        new BookmarkModel() { Title="秘迹搜索",Url="https://mijisou.com/" }
                    }
                },
            };

            if (keyValueModels.Any())
            {
                var updateDefinitions = new List>();
                foreach (var item in keyValueModels)
                {
                    if (item.Value == null)
                    {
                        updateDefinitions.Add(Builders.Update.Set(item.Key, BsonNull.Value));
                        continue;
                    }
                    string tempValueForStr = JsonSerializer.Serialize(item.Value);
                    var tempValueForObj = JsonSerializer.Deserialize<object>(tempValueForStr);
                    var tempValueType = ((JsonElement)tempValueForObj).ValueKind;
                    switch (tempValueType)
                    {
                        case JsonValueKind.Object:
                        case JsonValueKind.Array:
                            {
                                updateDefinitions.Add(Builders.Update.Set(item.Key, BsonSerializer.Deserialize<object>(tempValueForStr)));
                                break;
                            }
                        default:
                            {
                                updateDefinitions.Add(Builders.Update.Set(item.Key, item.Value));
                                break;
                            }
                    }
                }
                var updateDefinition = Builders.Update.Combine(updateDefinitions);
                string tempUpdateStr = GetJsonStingByUpdateDefinition(updateDefinition);
                //var modifiedCount1 = _collection.UpdateMany(Builders.Filter.Eq("_id", "1"), updateDefinition).ModifiedCount;
                string tempUpdateStrFromObj = "{ \"$set\" : " + tempUpdateObj.ToJson() + " }";
                //你会发现这个字符串中也是包含_t和_v,因为字典的值类型为object
                //驱动可能也是这么调用的，当然我没看源码
                string tempUpdateStrFromDictionary = "{ \"$set\" : " + tempUpdateDic.ToJson() + " }";
                //var modifiedCount2 = _collection.UpdateMany(Builders.Filter.Eq("_id", "1"), tempUpdateStrFromObj).ModifiedCount;
            }
            #endregion

            Console.WriteLine("Hello World!");
        }

        /// 

        /// 清空表（新增之前先清空）、批量添加（初始化一些数据）、查询操作
        /// 
        static void DeleteManyBatchAddFind()
        {
            var _client = new MongoClient("mongodb://localhost:27017");
            var _database = _client.GetDatabase("FormBuilder");
            var _collection = _database.GetCollection("UpdateArrayTest");
            //  如果表不存在不报错
            var delCount = _collection.DeleteMany(Builders.Filter.Empty).DeletedCount;
            var dtNow = DateTime.Now;
            List initUpdateArrayTestModels = new List()
            {
                new UpdateArrayTestModel()
                {
                    Id="1",Name="ddz001",Age=10,Valid=true,CreateDate=dtNow,LastUpdatedTime=dtNow,
                    Details=new OtherInfoModel(){ Height=169.5f, Weight=70.5f, Married=true },
                    Bookmarks=new List()
                    {
                        new BookmarkModel(){ Title="百度一下",Url="https://www.baidu.com/" },
                        new BookmarkModel(){ Title="必应",Url="https://cn.bing.com/" }
                    }
                },
                new UpdateArrayTestModel()
                {
                    Id="2",Name="ddz002",Age=20,Valid=true,CreateDate=dtNow,LastUpdatedTime=dtNow,
                    Details=new OtherInfoModel(){ Height=170.5f, Weight=71.5f, Married=true },
                    Bookmarks=new List()
                    {
                        new BookmarkModel(){ Title="搜狗搜索",Url="https://www.baidu.com/" },
                        new BookmarkModel(){ Title="多吉搜索",Url="https://www.dogedoge.com/" }
                    }
                }
            };
            _collection.InsertMany(initUpdateArrayTestModels);
            
            //这里的中文还没有问题
            var queryResult = _collection.Find(Builders.Filter.Empty).ToList();
            //这里的中文就变成了unicode,你可以试一试序列化选项
            var queryResultStr = JsonSerializer.Serialize(queryResult);
            JsonSerializerOptions jsonSerializerOptions = new JsonSerializerOptions{ Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping };
            var queryResultStr2 = JsonSerializer.Serialize(queryResult, jsonSerializerOptions);
        }

        /// 

        /// 更新数据和Object测试
        /// 
        static void UpdateArrayOrObject()
        {
            //  这里也遇到了同样的问题
            //      1、https://jira.mongodb.org/browse/CSHARP-1984
            //  其他相关
            //      1、https://www.codeproject.com/Tips/1268019/MongoDB-Csharp-How-to-Deserialize-a-JSON-Containin
            //      2、https://blog.csdn.net/mzl87/article/details/85488319
            var _client = new MongoClient("mongodb://localhost:27017");
            var _database = _client.GetDatabase("FormBuilder");
            var _collection = _database.GetCollection("UpdateArrayTest");
            List keyValueModels = new List()
            {
                new KeyValueModel(){ Key="Name",Value ="ddz001+++" },
                new KeyValueModel(){ Key="Age",Value = 11 },
                new KeyValueModel(){ Key="Valid",Value = false },
                new KeyValueModel(){ Key="LastUpdatedTime",Value=DateTime.Now },
                new KeyValueModel(){ Key="Details",Value= new OtherInfoModel(){ Height=179.5f,Weight=80.5f,Married=false } },
                new KeyValueModel()
                {
                    Key="Bookmarks",Value = new List()
                    {
                        new BookmarkModel() { Title="Yandex",Url="https://yandex.com/" },
                        new BookmarkModel() { Title="秘迹搜索",Url="https://mijisou.com/" }
                    }
                }
            };
            if (keyValueModels.Any())
            {
                var updateDefinitions = new List>();
                foreach (var item in keyValueModels)
                {
                    updateDefinitions.Add(Builders.Update.Set(item.Key, item.Value));
                }
                var updateDefinition = Builders.Update.Combine(updateDefinitions);
                string tempUpdateStr = GetJsonStingByUpdateDefinition(updateDefinition);
                //var modifiedCount = _collection.UpdateMany(Builders.Filter.Eq("_id", "1"), updateDefinition).ModifiedCount;
            }
        }

        /// 

        /// 将UpdateDefinition转为shell字符串
        /// 
        /// 
        /// 
        /// 
        static string GetJsonStingByUpdateDefinition(UpdateDefinition updateDefinition)
        {
            //  参考网址：
            //  https://qa.1r1g.com/sf/ask/2243338471/
            if (updateDefinition == null) return null;
            //updateDefinition.Render(_collection.DocumentSerializer,_collection.Settings.SerializerRegistry).ToString()
            return updateDefinition.Render(BsonSerializer.SerializerRegistry.GetSerializer(), BsonSerializer.SerializerRegistry).ToString();
        }
    }

    public class UpdateArrayTestModel
    {
        private string _id { get; set; }

        /// 

        /// 主键ID
        /// 
        public string Id { set => this._id = value; get => _id; }

        /// 

        /// 姓名
        /// 
        public string Name { get; set; }

        /// 

        /// 年龄
        /// 
        public int Age { get; set; }

        /// 

        /// 是否有效
        /// 
        public bool Valid { get; set; } = true;

        /// 

        /// 创建时间
        /// 
        [BsonDateTimeOptions(Kind = DateTimeKind.Unspecified)]
        public DateTime CreateDate { get; set; }

        /// 

        /// 最后一次更新时间
        /// 
        [BsonDateTimeOptions(Kind = DateTimeKind.Unspecified)]
        public DateTime LastUpdatedTime { get; set; }

        /// 

        /// 其他详细信息
        /// 
        public OtherInfoModel Details { get; set; }

        /// 

        /// 我的书签
        /// 
        public IEnumerable Bookmarks { get; set; }
    }

    public class OtherInfoModel
    {
        public float Height { get; set; }
        public float Weight { get; set; }
        public bool Married { get; set; } = true;
    }

    public class BookmarkModel
    {
        public string Title { get; set; }
        public string Url { get; set; }
    }

    public class KeyValueModel
    {
        public string Key { get; set; }
        public object Value { get; set; }
    }
}