Hi all! I have this message after my application is starting and fetching data from db.
InvalidOperationException: No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext
is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.
public class Startup
{
public Startup(IConfiguration configuration)
{
ConnectionString = Microsoft.Extensions.Configuration.ConfigurationExtensions.GetConnectionString(configuration, "SqlServer");
}
public static string ConnectionString;
// This method gets called by the runtime. Use this method to add services to the container.
// For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<TotalForumContext>(options => options.UseSqlServer(ConnectionString));
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseRouting();
app.UseEndpoints(endpoints =>
{
endpoints.MapGet("/", async context =>
{
Account temp;
using(var bag = new TotalForumContext())
temp = bag.Account.AsNoTracking().First();
await context.Response.WriteAsync(temp.Nick);
});
});
}
}
public partial class TotalForumContext : DbContext
{
public TotalForumContext()
{}
public TotalForumContext(DbContextOptions<TotalForumContext> options)
: base(options)
{
}
public virtual DbSet<Account> Account { get; set; }
}
Please follow the standard pattern below or read the official documentation.
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddControllersWithViews();
services.AddDbContext<TotalForumContext>(options =>
options.UseSqlServer(Configuration.GetConnectionString("SqlServer")));
}
Did you leave any code in the OnConfiguring(DbContextOptionsBuilder optionsBuilder), which overrides the dependency injection of the connectionstring established at Startup()?
If you find the post has answered your issue, then please mark post as 'answered'.
Maybe you should try the approach that has already been mentioned.
using System.Net;
using DAL;
using DAL.Models;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Diagnostics;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Serilog;
namespace WebApi3.x
{
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
Log.Logger = new LoggerConfiguration().ReadFrom.Configuration(configuration).CreateLogger();
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
//DAL
services.AddTransient<IDaoAuthor, DaoAuthor>();
services.AddTransient<IDaoPayroll, DaoPayroll>();
services.AddTransient<IDaoArticle, DaoArticle>();
services.AddDbContext<PublishingCompanyContext>(options => options.UseSqlServer(Configuration["ConnectionStrings:DefaultConnection"]));
services.AddMvc(options =>
{
options.Filters.Add(new ErrorHandlingFilter(Configuration));
});
services.AddControllers();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerfactory)
{
app.UseExceptionHandler(
options =>
{
options.Run(
async context =>
{
context.Response.StatusCode = (int)HttpStatusCode.InternalServerError;
context.Response.ContentType = "text/html";
var ex = context.Features.Get<IExceptionHandlerFeature>();
if (ex != null)
{
if (ex.Error.InnerException != null)
{
var err = $"<h1>Error: {ex.Error.Message} </h1>{ex.Error.StackTrace } {ex.Error.InnerException.Message} ";
await context.Response.WriteAsync(err).ConfigureAwait(false);
}
else
{
var err = $"<h1>Error: {ex.Error.Message} </h1>{ex.Error.StackTrace }";
await context.Response.WriteAsync(err).ConfigureAwait(false);
}
}
});
}
);
loggerfactory.AddSerilog();
app.UseRouting();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
});
}
}
}
using Microsoft.EntityFrameworkCore;
namespace DAL.Models
{
public partial class PublishingCompanyContext : DbContext
{
public PublishingCompanyContext(DbContextOptions<PublishingCompanyContext> options)
: base(options)
{
}
public virtual DbSet<Article> Article { get; set; }
public virtual DbSet<Author> Author { get; set; }
public virtual DbSet<Payroll> Payroll { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
if (!optionsBuilder.IsConfigured)
{
// optionsBuilder.UseSqlServer(new AppConfiguration(_options).GetPublishingCompanyConn());
}
}
}
If you find the post has answered your issue, then please mark post as 'answered'.
Where is the EF Dbcontext in what project? Where is EF installed in what project?
In the example code I am showing, EF is installed in the Data Access Layer, a classlib project, and the model is in the DAL too. The Startup.cs is in the WebAPI project where the DI for the connectionstring is established to be used by the EF Model Dbcontext
in the DAL.
Where did you get the initial example code you're trying to use?
Are you sure you have all EF Core components installed in the project? My DAL project using EF has the below.
I have created new project from mvc template and I have added all you mentioned packages. EF context and web-application stored in the same project. With OnConfiguring() it works fine but not with AddDbContext (error the same).
I have created new project from mvc template and I have added all you mentioned packages. EF context and web-application stored in the same project. With OnConfiguring() it works fine but not with AddDbContext (error the same).
Your initial code has logical bugs. It is not clear if you fixed these bugs.
I provided a standard pattern used in every tutorials and VS templates for adding connection string options from configuration. It's is not clear if you followed the recommendation. I assume not since you are still having this rather trivial issue.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using efmvctest.Entities;
using Microsoft.EntityFrameworkCore;
namespace efmvctest
{
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddControllersWithViews();
services.AddDbContext<TotalForumContext>(options => options.UseSqlServer(Configuration.GetConnectionString("SqlServer")));
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
else
{
app.UseExceptionHandler("/Home/Error");
// The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
app.UseHsts();
}
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllerRoute(
name: "default",
pattern: "{controller=Home}/{action=Index}/{id?}");
});
}
}
}
public string Index()
{
Account temp;
using(var context = new efmvctestContext())
temp = context.Account.First();
return temp.Nick;
}
in HomeController.
InvalidOperationException: No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext
is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.
use master
IF (EXISTS(SELECT TOP 1 1 FROM sys.sql_logins WHERE [name] = 'adminuser'))
DROP LOGIN adminuser;
go
drop database if exists efmvctest
go
create database efmvctest
EXEC sp_configure 'CONTAINED DATABASE AUTHENTICATION', 1
GO
RECONFIGURE
GO
USE [master]
GO
ALTER DATABASE efmvctest SET CONTAINMENT = PARTIAL
GO
use efmvctest
drop table if exists Account;
drop user if exists adminuser;
create login adminuser with password = 'Adminpassword1';
go
create user adminuser for login adminuser;
grant all to adminuser;
exec sp_addrolemember 'db_owner', 'adminuser'
go
create table Account
(
Nick NVARCHAR(MAX)
);
go
insert into Account values ('asdffadsasdf');
It's my simple db. Then, I am creating context using "dotnet ef dbcontext scaffold "Server=localhost;Database=efmvctest;User ID=adminuser; Password=Adminpassword1" Microsoft.EntityFrameworkCore.SqlServer -o Entities -f -v -d"
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddControllersWithViews();
services.AddDbContext<efmvctestContext>(options
=> options.UseSqlServer(Configuration.GetConnectionString("SqlServer")));
}
You did not pass the connection string option to the context.
But, ASP.NET Core uses constructor dependency injection. This concept is covered in every ASP.NET Core getting started tutorial and the Core SDK project templates have sample code that illustrate the same. The pattern has the following format.
public class HomeController : Controller
{
private readonly efmvctestContext _db;
public HomeController(efmvctestContext db)
{
_db = db;
}
Once properly configured you can use the content in all the Actions methods.
[HttpGet]
public IActionResult Index()
{
var results = _db.Person.Where(p => p.BusinessEntityId == 1);
return View(results);
}
I recommend going through the Getting Started tutorials in this site which covers these basic constructs.
Member
323 Points
379 Posts
EF Core - InvalidOperationException: No database provider has been configured for this DbContext
Apr 08, 2020 06:23 PM|Alex9|LINK
Hi all! I have this message after my application is starting and fetching data from db.
InvalidOperationException: No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.
Startup.cstemp = bag.Account.AsNoTracking().First();
public class Startup { public Startup(IConfiguration configuration) { ConnectionString = Microsoft.Extensions.Configuration.ConfigurationExtensions.GetConnectionString(configuration, "SqlServer"); } public static string ConnectionString; // This method gets called by the runtime. Use this method to add services to the container. // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940 public void ConfigureServices(IServiceCollection services) { services.AddDbContext<TotalForumContext>(options => options.UseSqlServer(ConnectionString)); } // This method gets called by the runtime. Use this method to configure the HTTP request pipeline. public void Configure(IApplicationBuilder app, IWebHostEnvironment env) { if (env.IsDevelopment()) { app.UseDeveloperExceptionPage(); } app.UseRouting(); app.UseEndpoints(endpoints => { endpoints.MapGet("/", async context => { Account temp; using(var bag = new TotalForumContext()) temp = bag.Account.AsNoTracking().First(); await context.Response.WriteAsync(temp.Nick); }); }); } }public partial class TotalForumContext : DbContext { public TotalForumContext() {} public TotalForumContext(DbContextOptions<TotalForumContext> options) : base(options) { } public virtual DbSet<Account> Account { get; set; } }{ "ConnectionStrings": { "SqlServer": "Server=localhost; Database=TotalForum; User Id=forumadminuser; Password=password" } }<ItemGroup> <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.3" /> <PackageReference Include="Microsoft.EntityFrameworkCore" Version="3.1.3" /> <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="3.1.3" /> </ItemGroup>What did happen? Why that doesn't work? Thank you.
All-Star
47661 Points
20887 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 08, 2020 06:48 PM|mgebhard|LINK
Please follow the standard pattern below or read the official documentation.
public class Startup { public Startup(IConfiguration configuration) { Configuration = configuration; } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { services.AddControllersWithViews(); services.AddDbContext<TotalForumContext>(options => options.UseSqlServer(Configuration.GetConnectionString("SqlServer"))); }Contributor
4473 Points
3786 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 08, 2020 06:58 PM|DA924|LINK
Did you leave any code in the OnConfiguring(DbContextOptionsBuilder optionsBuilder), which overrides the dependency injection of the connectionstring established at Startup()?
Member
323 Points
379 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 09, 2020 09:57 AM|Alex9|LINK
I have removed OnConfiguring method.
Contributor
4473 Points
3786 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 09, 2020 06:16 PM|DA924|LINK
Maybe you should try the approach that has already been mentioned.
using System.Net; using DAL; using DAL.Models; using Microsoft.AspNetCore.Builder; using Microsoft.AspNetCore.Diagnostics; using Microsoft.AspNetCore.Hosting; using Microsoft.AspNetCore.Http; using Microsoft.EntityFrameworkCore; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.DependencyInjection; using Microsoft.Extensions.Logging; using Serilog; namespace WebApi3.x { public class Startup { public Startup(IConfiguration configuration) { Configuration = configuration; Log.Logger = new LoggerConfiguration().ReadFrom.Configuration(configuration).CreateLogger(); } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { //DAL services.AddTransient<IDaoAuthor, DaoAuthor>(); services.AddTransient<IDaoPayroll, DaoPayroll>(); services.AddTransient<IDaoArticle, DaoArticle>(); services.AddDbContext<PublishingCompanyContext>(options => options.UseSqlServer(Configuration["ConnectionStrings:DefaultConnection"])); services.AddMvc(options => { options.Filters.Add(new ErrorHandlingFilter(Configuration)); }); services.AddControllers(); } // This method gets called by the runtime. Use this method to configure the HTTP request pipeline. public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerfactory) { app.UseExceptionHandler( options => { options.Run( async context => { context.Response.StatusCode = (int)HttpStatusCode.InternalServerError; context.Response.ContentType = "text/html"; var ex = context.Features.Get<IExceptionHandlerFeature>(); if (ex != null) { if (ex.Error.InnerException != null) { var err = $"<h1>Error: {ex.Error.Message} </h1>{ex.Error.StackTrace } {ex.Error.InnerException.Message} "; await context.Response.WriteAsync(err).ConfigureAwait(false); } else { var err = $"<h1>Error: {ex.Error.Message} </h1>{ex.Error.StackTrace }"; await context.Response.WriteAsync(err).ConfigureAwait(false); } } }); } ); loggerfactory.AddSerilog(); app.UseRouting(); app.UseAuthorization(); app.UseEndpoints(endpoints => { endpoints.MapControllers(); }); } } }using Microsoft.EntityFrameworkCore; namespace DAL.Models { public partial class PublishingCompanyContext : DbContext { public PublishingCompanyContext(DbContextOptions<PublishingCompanyContext> options) : base(options) { } public virtual DbSet<Article> Article { get; set; } public virtual DbSet<Author> Author { get; set; } public virtual DbSet<Payroll> Payroll { get; set; } protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder) { if (!optionsBuilder.IsConfigured) { // optionsBuilder.UseSqlServer(new AppConfiguration(_options).GetPublishingCompanyConn()); } } }Member
323 Points
379 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 10, 2020 04:20 PM|Alex9|LINK
Problem still exists after approach replacement.
Contributor
4473 Points
3786 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 10, 2020 06:30 PM|DA924|LINK
Where is the EF Dbcontext in what project? Where is EF installed in what project?
In the example code I am showing, EF is installed in the Data Access Layer, a classlib project, and the model is in the DAL too. The Startup.cs is in the WebAPI project where the DI for the connectionstring is established to be used by the EF Model Dbcontext in the DAL.
Where did you get the initial example code you're trying to use?
Are you sure you have all EF Core components installed in the project? My DAL project using EF has the below.
<ItemGroup> <PackageReference Include="Microsoft.EntityFrameworkCore" Version="3.1.1" /> <PackageReference Include="Microsoft.EntityFrameworkCore.Relational" Version="3.1.1" /> <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="3.1.1" /> <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="3.1.1"> <PrivateAssets>all</PrivateAssets> <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets> </PackageReference> </ItemGroup>Member
323 Points
379 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 10:35 AM|Alex9|LINK
I have created new project from mvc template and I have added all you mentioned packages. EF context and web-application stored in the same project. With OnConfiguring() it works fine but not with AddDbContext (error the same).
All-Star
47661 Points
20887 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 12:25 PM|mgebhard|LINK
Your initial code has logical bugs. It is not clear if you fixed these bugs.
I provided a standard pattern used in every tutorials and VS templates for adding connection string options from configuration. It's is not clear if you followed the recommendation. I assume not since you are still having this rather trivial issue.
Member
323 Points
379 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 07:02 PM|Alex9|LINK
using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Builder; using Microsoft.AspNetCore.Hosting; using Microsoft.AspNetCore.HttpsPolicy; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.DependencyInjection; using Microsoft.Extensions.Hosting; using efmvctest.Entities; using Microsoft.EntityFrameworkCore; namespace efmvctest { public class Startup { public Startup(IConfiguration configuration) { Configuration = configuration; } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { services.AddControllersWithViews(); services.AddDbContext<TotalForumContext>(options => options.UseSqlServer(Configuration.GetConnectionString("SqlServer"))); } // This method gets called by the runtime. Use this method to configure the HTTP request pipeline. public void Configure(IApplicationBuilder app, IWebHostEnvironment env) { if (env.IsDevelopment()) { app.UseDeveloperExceptionPage(); } else { app.UseExceptionHandler("/Home/Error"); // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts. app.UseHsts(); } app.UseHttpsRedirection(); app.UseStaticFiles(); app.UseRouting(); app.UseAuthorization(); app.UseEndpoints(endpoints => { endpoints.MapControllerRoute( name: "default", pattern: "{controller=Home}/{action=Index}/{id?}"); }); } } }All-Star
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Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 07:43 PM|mgebhard|LINK
I'm glad you followed the standard pattern and fixed this issue.
Member
323 Points
379 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 08:00 PM|Alex9|LINK
public string Index() { Account temp; using(var context = new efmvctestContext()) temp = context.Account.First(); return temp.Nick; }in HomeController.
InvalidOperationException: No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.
Microsoft.EntityFrameworkCore.Internal.DbContextServices.Initialize(IServiceProvider scopedProvider, IDbContextOptions contextOptions, DbContext context)
Microsoft.EntityFrameworkCore.DbContext.get_InternalServiceProvider()
Microsoft.EntityFrameworkCore.DbContext.get_DbContextDependencies()
Microsoft.EntityFrameworkCore.DbContext.get_Model()
Microsoft.EntityFrameworkCore.Internal.InternalDbSet<TEntity>.get_EntityType()
Microsoft.EntityFrameworkCore.Internal.InternalDbSet<TEntity>.CheckState()
Microsoft.EntityFrameworkCore.Internal.InternalDbSet<TEntity>.get_EntityQueryable()
Microsoft.EntityFrameworkCore.Internal.InternalDbSet<TEntity>.System.Linq.IQueryable.get_Provider()
System.Linq.Queryable.First<TSource>(IQueryable<TSource> source)
efmvctest.Controllers.HomeController.Index() in
HomeController.cs- temp = context.Account.First();
</div>lambda_method(Closure , object , object[] )
Microsoft.Extensions.Internal.ObjectMethodExecutor.Execute(object target, object[] parameters)
Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor+SyncObjectResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, object controller, object[] arguments)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeActionMethodAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeNextActionFilterAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)
use master IF (EXISTS(SELECT TOP 1 1 FROM sys.sql_logins WHERE [name] = 'adminuser')) DROP LOGIN adminuser; go drop database if exists efmvctest go create database efmvctest EXEC sp_configure 'CONTAINED DATABASE AUTHENTICATION', 1 GO RECONFIGURE GO USE [master] GO ALTER DATABASE efmvctest SET CONTAINMENT = PARTIAL GO use efmvctest drop table if exists Account; drop user if exists adminuser; create login adminuser with password = 'Adminpassword1'; go create user adminuser for login adminuser; grant all to adminuser; exec sp_addrolemember 'db_owner', 'adminuser' go create table Account ( Nick NVARCHAR(MAX) ); go insert into Account values ('asdffadsasdf');It's my simple db. Then, I am creating context using "dotnet ef dbcontext scaffold "Server=localhost;Database=efmvctest;User ID=adminuser; Password=Adminpassword1" Microsoft.EntityFrameworkCore.SqlServer -o Entities -f -v -d"
public Startup(IConfiguration configuration) { Configuration = configuration; } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { services.AddControllersWithViews(); services.AddDbContext<efmvctestContext>(options => options.UseSqlServer(Configuration.GetConnectionString("SqlServer"))); }{ "Logging": { "LogLevel": { "Default": "Information", "Microsoft": "Warning", "Microsoft.Hosting.Lifetime": "Information" } }, "ConnectionStrings": { "SqlServer": "Server=localhost; Database=efmvctest; User ID=adminuser; Password=Adminpassword1" } }I get correct string in browser when I'm using OnConfiguring. But with AddDbContext problem still exists. Any additions?
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20887 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 08:32 PM|mgebhard|LINK
You did not pass the connection string option to the context.
But, ASP.NET Core uses constructor dependency injection. This concept is covered in every ASP.NET Core getting started tutorial and the Core SDK project templates have sample code that illustrate the same. The pattern has the following format.
public class HomeController : Controller { private readonly efmvctestContext _db; public HomeController(efmvctestContext db) { _db = db; }Once properly configured you can use the content in all the Actions methods.
[HttpGet] public IActionResult Index() { var results = _db.Person.Where(p => p.BusinessEntityId == 1); return View(results); }I recommend going through the Getting Started tutorials in this site which covers these basic constructs.
https://docs.microsoft.com/en-us/aspnet/core/data/ef-mvc/?view=aspnetcore-3.1
Member
323 Points
379 Posts
Re: EF Core - InvalidOperationException: No database provider has been configured for this DbCont...
Apr 11, 2020 08:44 PM|Alex9|LINK
Thank you very much. Now it's working fine.