[MongoDB] Array operations

Summary

In the actual development encountered updating the value of an array in a document, here is a record.

The driver used here is

Using Mongodb.bson;
Using Mongodb.driver;

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Demo

usingMongodb.bson;usingMongodb.driver;usingMongoDB.Driver.Builders;usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;usingSystem.Threading.Tasks;namespacewolfy.mongodb{classProgram {Static voidMain (string[] args) {        }    }    classMongohelper {Private Static ReadOnly string_db =""; Private Static ReadOnly string_col =""; Private Static ReadOnly string_IP =""; Private Static ReadOnly string_user =""; Private Static ReadOnly string_pwd =""; Private Static ReadOnly string_connstr =string. Format ("Mongodb://{0}:{1}@{2}:27017/{3}", _user, _pwd, _ip, _db); /// <summary>        ///add friend to a UserID and add if it does not exist in the array/// </summary>        /// <param name= "UserId" ></param>        /// <param name= "friendID" ></param>        /// <returns></returns>         Public Static BOOLUpdateorinsert (stringUseridstringfriendID) {            varCol =GetCollection (); varquery =Newquerydocument {{"userId", userId},Newquerydocument {{"$nin",NewBsonarray ().            ADD (friendID)}}}; varUpdate = Update.push ("Friends", friendid). INC ("Count",1); returnCol. Update (query, update, Updateflags.none).        Ok; }        Private StaticMongocollection<bsondocument>GetCollection () {mongoclient client=Newmongoclient (_CONNSTR); Mongoserver Server=client.            Getserver (); vardb =server.            Getdatabase (_db); varCol =db.            GetCollection (_col); returnCol; }        /// <summary>        ///remove a friend from a property/// </summary>        /// <param name= "UserId" ></param>        /// <param name= "friendID" ></param>        /// <returns></returns>         Public Static BOOLRemovefriend (stringUseridstringfriendID) {            varCol =GetCollection (); varquery =Newquerydocument {{"userId", userId}}; MongoDB.Driver.Builders.UpdateBuilder Builder=NewMongoDB.Driver.Builders.UpdateBuilder (); Builder. Pull ("Friends", friendID); returnCol. Update (query, builder, Updateflags.none).        Ok; }        /// <summary>        ///Update Field values/// </summary>        /// <param name= "UserId" ></param>        /// <param name= "dic" ></param>        /// <returns></returns>         Public Static BOOLUpdatefields (stringUserId, dictionary<string,Object>dic) {varCol =GetCollection (); varquery =Newquerydocument {{"userId", userId}}; MongoDB.Driver.Builders.UpdateBuilder Builder=NewMongoDB.Driver.Builders.UpdateBuilder (); foreach(varIteminchDiC. Keys) {Builder.            Set (item, Bsonvalue.create (Dic[item])); } builder. Set ("DT", DateTime.Now); returnCol. Update (query, builder, Updateflags.upsert).        Ok; }    }}

Code

These are the actions in your friends list. If the buddy list already exists, it is no longer added or added. Omit to do business with C # in judgment. In fact, there are many, can be given to MongoDB to do, can be in the code a lot less if-else.

[MongoDB] Array operations