How to change database name in dbcontext connection string at runtime

Question

My Asp.Net MVC application is setup as follows. There are 4 projects in solution.

• ge.Web
• ge.BLL
• ge.Core
• ge.Entities

<

Answer 1

You have two ways

1)

    using System.Data.SqlClient;

         public class Repository<TEntity> : IRepository<TEntity> where TEntity:class
        {
            protected readonly GEContext context;


            public Repository(string connString, string schoolCode) {
                context = new GEContext(connString);
                var connection = new SqlConnectionStringBuilder(context.Database.Connection.ConnectionString);
                connection.InitialCatalog = "YOUR_PREFIX_FROMSOMEWHERE"+schoolCode;
                context.Database.Connection.ConnectionString = connection.ConnectionString;
            }
         }

2) if you wants to switch connection when it opened before use ChangeDatabase:

//open connection if it close
    context.Database.Connection.ChangeDatabase("DATABASE-NAME");

NOTE: if use ChangeDatabase connection should be already opened

FOR UPDATE3:

You need to do somethink like this:

 public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
    {
        public ApplicationDbContext()
            : base("DefaultConnection", throwIfV1Schema: false)
        {

        }

        public ApplicationDbContext(string schoolCode)
            : base(schoolCode)
        {
            var connection = new SqlConnectionStringBuilder(this.Database.Connection.ConnectionString);
            connection.InitialCatalog = "YOUR_PREFIX_FROMSOMEWHERE" + schoolCode;
            this.Database.Connection.ConnectionString = connection.ConnectionString;
        }

        public static ApplicationDbContext Create()
        {
            return new ApplicationDbContext();
        }
    }

in account controller:

public ApplicationSignInManager SignInManager
        {
            get
            {

                if (_signInManager == null)
                {
                    var code = HttpContext.Request.Form.Get("SchoolCode");//Get from FORM\QueryString\Session whatever you wants
                    if (code != null)
                    {
                        HttpContext.GetOwinContext().Set<ApplicationSignInManager>(new ApplicationSignInManager(_userManager, HttpContext.GetOwinContext().Authentication));
                    }
                    _signInManager = HttpContext.GetOwinContext().Get<ApplicationSignInManager>();
                }

                return _signInManager;
            }
            private set
            {
                _signInManager = value;
            }
        }

 public ApplicationUserManager UserManager
        {
            get
            {
                if (_userManager == null)
                {
                    var code = HttpContext.Request.Form.Get("SchoolCode");//Get from FORM\QueryString\Session whatever you wants
                    if (code != null)
                    {
                        var appDbContext = new ApplicationDbContext(code);

                        HttpContext.GetOwinContext().Set<ApplicationDbContext>(appDbContext);
                        HttpContext.GetOwinContext().Set<ApplicationUserManager>(new ApplicationUserManager(new UserStore<ApplicationUser>(appDbContext))); //OR USE your specified create Method
                    }
                    _userManager = HttpContext.GetOwinContext().GetUserManager<ApplicationUserManager>();
                }
                return _userManager;
            }
            private set
            {
                _userManager = value;
            }
        }

Your problem is in Store of UserManager is created before you change your OWIN context, in this case better to use DI like here

Answer 2

You can change the database for an open connection

context.Database.GetDbConnection().ChangeDatabase("");

Answer 3

I resolved it with the help of itikhomi..Posting the final code..

ApplicationDbContext

public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext("name=GEContext");
    }

AccountController

 public ApplicationUserManager UserManager {
        get
        {
            if (System.Web.HttpContext.Current.Session["SchoolCode"] == null)
                return _userManager ?? HttpContext.GetOwinContext().GetUserManager<ApplicationUserManager>();
            else
            {
                var appDbContext = ApplicationDbContext.Create(System.Web.HttpContext.Current.Session["SchoolCode"].ToString());//new ApplicationDbContext("name=GEContext", System.Web.HttpContext.Current.Session["SchoolCode"].ToString());

                HttpContext.GetOwinContext().Set<ApplicationDbContext>(appDbContext);
                HttpContext.GetOwinContext().Set<ApplicationUserManager>(new ApplicationUserManager(new UserStore<ApplicationUser, Role, int, UserLogin, UserRole, UserClaim>(appDbContext)));

                return HttpContext.GetOwinContext().GetUserManager<ApplicationUserManager>();
            }
        }
        private set
        {
            _userManager = value;
        }
    }