AutoMapper | A convention-based object-object mapper in .NET | Object-Relational Mapping library

I have searched on Stack Overflow and googled about it but I haven't been able to find any help or suggestion on this.

I have a generic class BusinessResult that have a value property, and I want to create an Automapper in order to map value property of BusinessResult to value property of BusinessResult.

Any suggestion to do that with Automapper in .NET Core 5?

I am trying to figure out how to serialize to a json object and skip serializing properties whose values are empty lists. I am not using Newtonsoft json

I'm trying to map a password (comming in from a new user) to passwordHash and passwordSalt. The function I'm using to create these two values generates both values at the same time and return them. Is it possible to map to both of these values from the single password using Automapper? This is my attempt below.

How to configure AutoMapper in ASP.Net Core 6

I have a project which is written in .Net 3.1 so we had Startup.cs class.

I am migrating it to .net core 6

now when I put the following configuration in my .Net 6 Program.cs

I am using automapper in my Program.cs like this:

I discovered one problem while creating my project. If someone refer to the issue I will be grateful. In my project I use a layered model. The repository layer (data access layer) that communicates with the database (DB) and the service layer (business logic layer) in which services and objects are implemented (data transfer object).

As a result, there is a problem with the dbSet.Update method. When object (obj) comes into Update method as parameter, during the method call of the _db.Entry(dbSet.Local.FirstOrDefault(i => i.Id == obj.Id) ?? obj).State = EntityState.Modified or _db.Update(dbSet.Local.FirstOrDefault(i => i.Id == obj.Id) ?? obj) in the case of the first user's update (like from "view.xaml") obj is update and changes saving in the database (because dbSet.Local.FirstOrDefault(i => i.Id == obj.Id) returns null and obviously my obj gets into the _db.Update method). In case of a repeated user's update (in the "view.xaml" view) object obj -- when it gets into the _db.Update(dbSet.Local.FirstOrDefault(i => i.Id == obj.Id) ?? obj) method, it isn't take account, as the data context already tracks it and in the _db.Update method gets an object from dbSet.Local.FirstOrDefault(i => i.Id == obj.Id). Everything would be fine if this object in dbSet.Local was updated according to the type that comes from the user. However, this is not the case, it is tracked but not changed when the user edits its properties. It is not tracked properly rather due to the fact that I use services and, accordingly, data transfer object entities.

In view of the foregoing, I have a question. How to make to update entity (by a new modified object) that are tracked, or how to manually assign the necessary object in dbSet.Local to replace the one stored there? or how to make Microsoft.EntityFrameworkCore.ChangeTracking not track changes to my objects in any way?

In order to make changes not tracked I used the QueryTrackingBehavior.NoTracking parameter for the DbContextOptionsBuilder entity, but this only helps on the first load, and tracking is still used when the data is updated further. I also used the dbSet.Local.Clear() methods, but this is a bad idea, as data updating due to the deletion of the previous data from the database (like delete 20 rows from table and add one updated).

Good morning everybody. I am creating an application on .net 5 it was working fine til last night and now i am testing and i am receiving an error message even without any change on the code so i really don't know why.

That is the error:

I created a .Net Core 5 API having 2 types of models:

• Entities (used by Entity Framework Core)
• DTOs (Data Transfer Objects for requests and responses, replacing "{Property}Id" properties from Entity with "{Property}Code" in DTO)

I have a service responsible of mapping Entities types to Dtos types added as singleton in ConfigureServices:

services.AddSingleton(typeof(IEntityDtoMappingProvider), typeof(EntityDtoMappingProvider));

The service EntityDtoMappingProvider has a method which returns the mapping between Entities and Dtos for an assembly through reflection described by this interface:

I'm building a .NET 5 REST API based on CQRS/MediatR and I noticed a linear memory increase when stress testing my application. I did some profiling and saw a large number of object instances from the namespace System.Linq.Expression was taking up all the space. All these instances are related to the MapperConfiguration of AM.

I use AutoMapper to map my entities to the DTOs, to do so I mainly use the following ProjectTo extension method :