Error when adding Controler to ASP.NET MVC

Question

Good morning, I am making a small solution using ASP.NET MVC with Entity Framework 6 to meet a work of my course. I believe the context class:

namespace WillianRibeiro.EstudandoMVC.Web.Data{
public class EstudandoMVCContext : DbContext
{
    public EstudandoMVCContext()
        :base("EstudandoMVC_Desenv")
    {
    }
    public DbSet<Usuario> Usuario { get; set; }
 }  }

I created the Model:

namespace WillianRibeiro.EstudandoMVC.Web.Data{
public class EstudandoMVCContext : DbContext
{
    public EstudandoMVCContext()
        :base("EstudandoMVC_Desenv")
    {

    }

    public DbSet<Usuario> Usuario { get; set; }

 }}

I set up the web config:

    <connectionString>
<add name="EstudandoMVC_Desenv" connectionString="Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=E:\OneDrive\Projetos ASP NET\COPEL\WillianRibeiro.EstudandoMVC\WillianRibeiro.EstudandoMVC.Web\App_Data\EstudandoMVC_BD.mdf;Integrated Security=True" providerName="System.Data.SqlClient" />

The problem occurs when I add the "User" controller I am trying to add the MVC 5 controller with the views and using the Entity Framework. I do all the configuration and when I have created the error: "Error executing selected code generator: An exception was triggered by the destination of a call".

I’ve gone over the code several times and I can’t solve it.

Answer 1

In startup.Cs:

`public void ConfigureServices(IServiceCollection services)
        {
            var connection = Configuration["ConexaoMySql:MySqlConnectionString"];
            services.AddDbContext<---SeuContexto--->(options =>
                options.UseMySql(connection)
            );
            // Add framework services.
            services.AddMvc();
        }`

Answer 2

Connecting to Visual Studio 2017 - ASP NET MVC - Mysql 5.5 was having the same problem reported by the colleague.

Error while creating Controller:

"Error running selected code generator: An exception was triggered by a call destination"

Following the guidelines above by adjusting the "Context", I was able to solve the problem.

Thank you.

Answer 3

You need to create a Class context and the Class User (which refers to your Table), would be more or less like this:

This is the Context class ,where you will reference your tables

public partial class EstudandoMVCContext: DbContext
{
    public EstudandoMVCContext()
        : base("name=EstudandoMVC_Desenv")//Refere ao nome da sua conexão
    {
    }

    public virtual DbSet<Usuario> Usuario { get; set; }


    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Usuario>()
            .Property(e => e.nomeUsuario)
            .IsUnicode(false);

    }
}

And here will be your User class (representing your table)

[Table("Usuario")]
public partial class Usuario
{
    [Key]
    public int idUsario { get; set; }

    [StringLength(50)]
    public string nomeUsuario { get; set; }
}

If you already have the tables done in the database ,it is easier to let the Entity Framework itself generate these classes.