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c#mongodbmongodb-.net-driver

Mongodb How to Update many documents using C# driver

Please be so kind to help.

I got List of documents from xml parsing service and trying update it in DB.

I create fiter builder like .

var filter = Builders<T>.Filter.In("Id", List<T>);

and update builder like.

var update = Builders<T>.Update.Set("T.Property", List<T> )

and using UpdateManyAsync() updating documents in DB, but changings not apply.

How I could update documents in 1 step ?

Solution

  • Hello this is a sample using a .NET core 3.1 console application.

    This is the csproj file:

    <Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp3.1</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="MongoDB.Driver" Version="2.13.1" />
  </ItemGroup>

</Project>

    This is the code inside of the Program.cs file:

    using MongoDB.Bson.Serialization.Attributes;
using MongoDB.Driver;
using System;
using System.Collections.Generic;
using System.Threading.Tasks;

namespace MongoUpdateMany
{
  public static class Program
  {
    public static async Task Main(string[] args)
    {
      const string databaseName = "test";
      const string collectionName = "students";

      var client = new MongoClient();
      var database = client.GetDatabase(databaseName);
      var collection = database.GetCollection<Student>(collectionName);

      // just to be sure the test data are clean, nothing to do with the update sample
      await database.DropCollectionAsync(collectionName).ConfigureAwait(false);

      // create a bunch of students
      var id = 1;

      var enrico = new Student()
      {
        Name = "Enrico",
        Id = id++,
        IsActive = false
      };
      var luca = new Student
      {
        Name = "Luca",
        Id = id++,
        IsActive = false
      };
      var giulia = new Student
      {
        Name = "Giulia",
        Id = id++,
        IsActive = true
      };

      // fill the collection
      await collection.InsertManyAsync(new List<Student> { enrico, giulia, luca }).ConfigureAwait(false);

      // update many
      var ids = new List<int> { enrico.Id, luca.Id };

      var filter = Builders<Student>
        .Filter
        .In(x => x.Id, ids);

      var update = Builders<Student>
        .Update
        .Set(x => x.IsActive, true);

      await collection.UpdateManyAsync(filter, update).ConfigureAwait(false);

      // verify updating the docs worked
      await collection
        .Find(student => ids.Contains(student.Id))
        .ForEachAsync(student => Console.WriteLine($"Name: {student.Name} IsActive: {student.IsActive}"))
        .ConfigureAwait(false);

      Console.WriteLine();
      Console.WriteLine("Press enter to close...");
      Console.ReadLine();
    }
  }

  public class Student
  {
    [BsonId]
    public int Id { get; set; }
    public string Name { get; set; }
    public bool IsActive { get; set; }
  }
}

    Here is some useful links to learn how to use the official C# driver for mongodb: