Change Context according to application

Question

I need to point out in the web part what context the system will use.

My project is divided as follows:

After its completion I had to "replicate" it, but using another bank. The tables are equal does not change anything, but it is in another database because it is another system. I just need to change the connection string of the web.config. I find "VERY WRONG" to leave two projects IDENTICAL only with the different connection string.

namespace RepositorioEF
{
public class Contexto : DbContext
{
    public DbSet<Cartas> Carta {get;set;}
    public DbSet<Clientes> Clientes { get; set; }
    public DbSet<Loja_Carrossel> Carrossel { get; set; }
    public DbSet<Loja_Menus> Menu { get; set; }
    public DbSet<Loja_Produtos> Produto { get; set; }
    public DbSet<Loja_Submenus> Submenu { get; set; }
    public DbSet<Pedidos> Pedido { get; set; }
    public DbSet<Pedidos_Itens> PedidoItem { get; set; }
    public DbSet<Pedidos_Status> PedidoStatus { get; set; }
    public DbSet<Loja_Codigo> Codigo { get; set; }
    public DbSet<Loja_Usuarios> Usuarios { get; set; }
    public DbSet<Loja_ActionsLog> ActionsLog { get; set; }


    public Contexto()
        : base("BancoDados")
    {
        Database.SetInitializer<Contexto>(null);
    }
}
}

This is the class of my context and I don’t know how to make an "IF" for a certain option. I thought about adding another constructor to use the other string Connection, but I don’t know if it is the most appropriate way.

And I call context with this class:

namespace RepositorioEF
{
public class ClientesRepositorioEF : IRepositorio<Clientes>
{
    private readonly Contexto contexto;

    public ClientesRepositorioEF()
    {
        contexto = new Contexto();
    }
}
}

Answer 1

Just have more options in your context constructor:

public Contexto()
    : base("BancoDados")
{
    Database.SetInitializer<Contexto>(null);
}

public Contexto(String nomeDaConnectionString)
    : base(nomeDaConnectionString)
{

}

Pass the name of ConnectionString at the time of instantiation:

public class ClientesRepositorioEF : IRepositorio<Clientes>
{
    private readonly Contexto contexto1;
    private readonly Contexto contexto2;

    public ClientesRepositorioEF()
    {
        contexto1 = new Contexto();
        contexto2 = new Contexto("MinhaSegundaConnectionString");
    }
}

To use the ConnectionString standard, just pass nothing as argument.

Answer 2

Utilize Web.config Transformation Syntax to change the Connection strings when published:

In Solution explorer, search for: Web.Release.config and change the desired session:

<connectionStrings>
    <add
        xdt:Locator="Match(name)" xdt:Transform="Replace"
        name="{nome-da-connection-string}"
        connectionString="{connection-string-nova}" providerName="System.Data.SqlClient" />
</connectionStrings>

In the post settings select the desired profile:

You can create as many profiles as you want:

And add new transformations to Web.config: