ASP.net MVC 4只有1个数据库？

Question

I'm using a shared database solution and I only get access to one database. How can I make my MVC application only use this 1 database for all its data? Is this possible?

Answer 1

MVC doesn't require a database to run. You can write all the code that accesses the database, so you are in complete control of how many databases it will access.

Answer 2

By not using any of the Microsoft-provided Membership, Session and Profile providers, which create their own database called "aspnet".

(Requires changes in the web.config file)

Other than that, StanK is right, you can or rather have to write your code yourself.
BTW, if it isn't a Sql-Server database, you might need another ado.net provider than the one build into the .NET framework.

Here an example for code to access the database:

protected System.Data.Common.DbProviderFactory m_providerFactory = null;

 protected System.Data.SqlClient.SqlConnectionStringBuilder m_ConnectionString;



        public System.Data.Common.DbProviderFactory GetFactory()
        {
            System.Data.Common.DbProviderFactory providerFactory = null;
            providerFactory = System.Data.Common.DbProviderFactories.GetFactory("System.Data.SqlClient");
            return providerFactory;
        } // End Function GetFactory



 public System.Data.IDbConnection GetConnection()
        {
            System.Data.SqlClient.SqlConnection sqlc = new System.Data.SqlClient.SqlConnection("ConnectionString");

            return sqlc;
        } // End Function GetConnection



public System.Data.IDbConnection GetConnection(string strInitialCatalog)
        {
            if (string.IsNullOrEmpty(strInitialCatalog))
            {
                return GetConnection();
            }








            System.Data.SqlClient.SqlConnection sqlc = null;




            lock (this.m_ConnectionString)
            {
                string strOrigInitialCatalog = this.m_ConnectionString.InitialCatalog;
                this.m_ConnectionString.InitialCatalog = strInitialCatalog;
                sqlc = new System.Data.SqlClient.SqlConnection(this.m_ConnectionString.ConnectionString);
                this.m_ConnectionString.InitialCatalog = strOrigInitialCatalog;
                strOrigInitialCatalog = null;
            }




            return sqlc;
        }




    public override System.Data.IDbCommand CreateCommand()
    {
        return CreateCommand("");
    } // End Function CreateCommand


    public override System.Data.IDbCommand CreateCommand(string strSQL)
    {
        System.Data.IDbCommand idbc = this.m_providerFactory.CreateCommand();
        idbc.CommandText = strSQL;

        return idbc;
    } // End Function CreateCommand




public System.Data.DataTable GetDataTable(System.Data.IDbCommand cmd, string strDb)
        {
            System.Data.DataTable dt = new System.Data.DataTable();

            using (System.Data.IDbConnection idbc = GetConnection(strDb))
            {

                lock (idbc)
                {

                    lock (cmd)
                    {

                        try
                        {
                            cmd.Connection = idbc;

                            using (System.Data.Common.DbDataAdapter daQueryTable = this.m_providerFactory.CreateDataAdapter())
                            {
                                daQueryTable.SelectCommand = (System.Data.Common.DbCommand)cmd;
                                daQueryTable.Fill(dt);
                            } // End Using daQueryTable



                        } // End Try
                        catch (System.Data.Common.DbException ex)
                        {
                            //COR.Debug.MsgBox("Exception executing ExecuteInTransaction: " + ex.Message);
                            Log("cMS_SQL.GetDataTable(System.Data.IDbCommand cmd)", ex, cmd.CommandText);
                        }// End Catch
                        finally
                        {
                            if (idbc != null && idbc.State != System.Data.ConnectionState.Closed)
                                idbc.Close();
                        } // End Finally

                    } // End lock cmd

                } // End lock idbc

            } // End Using idbc

            return dt;
        } // End Function GetDataTable



public override System.Data.DataTable GetDataTable(string strSQL, string strInitialCatalog)
{
    System.Data.DataTable dt = null;

    using (System.Data.IDbCommand cmd = this.CreateCommand(strSQL))
    {
        dt = GetDataTable(cmd, strInitialCatalog);
    } // End Using cmd

    return dt;
} // End Function GetDataTable

Usage:

GetDataTable("SELECT * FROM T_User", "DB_NAME");

And code to get the provider factory for non-registered providers:

        public System.Data.Common.DbProviderFactory GetFactory(Type tAssemblyType)
        {
            return GetFactory(tAssemblyType.AssemblyQualifiedName);
        }


        public virtual System.Data.Common.DbProviderFactory GetFactory(string assemblyType)
        {

#if TARGET_JVM // case insensitive GetType is not supported
            Type type = Type.GetType (assemblyType, false);
#else
            Type type = Type.GetType(assemblyType, false, true);
#endif
            if (type != null && type.IsSubclassOf(typeof(System.Data.Common.DbProviderFactory)))
            {
                // Provider factories are singletons with Instance field having
                // the sole instance
                System.Reflection.FieldInfo field = type.GetField("Instance", System.Reflection.BindingFlags.Public |
                                                 System.Reflection.BindingFlags.Static);
                if (field != null)
                {
                    return (System.Data.Common.DbProviderFactory)field.GetValue(null);
                    //return field.GetValue(null) as DbProviderFactory;
                }

            }

            throw new System.Configuration.ConfigurationErrorsException("DataProvider is missing!");
            //throw new System.Configuration.ConfigurationException("DataProvider is missing!");
        } // End Function GetFactory

And an example (getting the postgre factory):

public System.Data.Common.DbProviderFactory GetFactory()
        {
            //AddFactoryClasses();
            System.Data.Common.DbProviderFactory providerFactory = null;
            providerFactory = this.GetFactory(typeof(Npgsql.NpgsqlFactory));

            return providerFactory;
        } // End Function GetFactory

Answer 3

Im guessing here but are you using Entity Framework for data access and want to also make use of the Membership provider and are having trouble getting the membership schema in the same DB as your Entity Framework tables - if so try the follow:

Leave you're entity framework (or any other DB things youve already created exactly where they are) then specify which database you'd like to create the Membership schema in by using aspnet_regsql.exe .

This tool effectively creates the tables for you either via command line or a nice setup wizard.

See this tutorial here http://www.asp.net/web-forms/tutorials/security/membership/creating-the-membership-schema-in-sql-server-vb pay particular attention to the section entitled Step 2: Adding the SqlMembershipProvider Schema to the Database .

Here's the important bit pasted from the above article for convenience:

Step 2: Adding the SqlMembershipProvider Schema to the Database

The SqlMembershipProvider requires a particular set of tables, views, and stored procedures to be installed in the user store database. These requisite database objects can be added using the aspnet_regsql.exe tool. This file is located in the %WINDIR%\\Microsoft.Net\\Framework\\v2.0.50727\\ folder.

Note: The aspnet_regsql.exe tool offers both command line functionality and a graphical user interface. The graphical interface is more user friendly and is what we will examine in this tutorial. The command line interface is useful when the addition of the SqlMembershipProvider schema needs to be automated, such as in build scripts or automated testing scenarios.

The aspnet_regsql.exe tool is used to add or remove ASP.NET application services to a specified SQL Server database. The ASP.NET application services encompass the schemas for the SqlMembershipProvider and SqlRoleProvider, along with the schemas for the SQL-based providers for other ASP.NET 2.0 frameworks. We need to provide two bits of information to the aspnet_regsql.exe tool:

Whether we want to add or remove application services, and The database from which to add or remove the application services schema In prompting for the database to use, the aspnet_regsql.exe tool asks us to provide the name of the server the database resides on, the security credentials for connecting to the database, and the database name. If you are using the non-Express Edition of SQL Server, you should already know this information, as it is the same information you must provide through a connection string when working with the database through an ASP.NET web page. Determining the server and database name when using a SQL Server 2005 Express Edition database in the App_Data folder, however, is a bit more involved.

Answer 4

Sorry for the newb question, guys, and thanks for all the answers! Here is what worked for me.

First, Have my DBContext data model look like...

public class CDBContext : DbContext    
{
    public DbSet<tbl1> tbl1{ get; set; }
    public DbSet<tbl2> tbl2{ get; set; }
    public DbSet<tbl3> tbl3{ get; set; }
    public DbSet<tbl4> tbl4{ get; set; }
}

Then, have an example table model look like

public class tbl1
{
    public int ID { get; set; }

    public string Var2{ get; set; }

    public string Var3{ get; set; }
}

Next, I use the "Add->Controller" Wizard, selecting the appropriate data model (tbl1) and the appropriate context (CDBContext). I can then do this for model tbl2, tbl3, and tbl4! Each model becomes a table in the database instead of using an entire table for a database (which is what I was doing before).

It appears to work now, thanks again!