Code: Select all
Microsoft.EntityFrameworkCore.Design.OperationException:
Unable to create an object of type 'BlogContext'.
For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728
< /code>
Wenn ich das Flag --verbose füge, erhalte ich folgende Ausgabe: < /p>
Build started...
dotnet build blog/app/app.csproj /verbosity:quiet /nologo
Build succeeded.
0 Warning(s)
0 Error(s)
Time Elapsed 00:00:02.50
Build succeeded.
Finding DbContext classes...
Finding IDesignTimeDbContextFactory implementations...
Finding application service provider in assembly 'app'...
Finding Microsoft.Extensions.Hosting service provider...
No static method 'CreateHostBuilder(string[])' was found on class 'Program'.
No application service provider was found.
Finding DbContext classes in the project...
Found DbContext 'BlogContext'.
Microsoft.EntityFrameworkCore.Design.OperationException: Unable to create an object of type 'BlogContext'. For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728
---> System.InvalidOperationException: Unable to resolve service for type 'Microsoft.EntityFrameworkCore.DbContextOptions`1[app.Data.BlogContext]' while attempting to activate 'app.Data.BlogContext'.
at Microsoft.Extensions.DependencyInjection.ActivatorUtilities.ConstructorMatcher.CreateInstance(IServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ActivatorUtilities.CreateInstance(IServiceProvider provider, Type instanceType, Object[] parameters)
at Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetServiceOrCreateInstance(IServiceProvider provider, Type type)
at Microsoft.EntityFrameworkCore.Design.Internal.DbContextOperations.c__DisplayClass13_4.b__13()
Unable to create an object of type 'BlogContext'. For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728
Code: Select all
// Program.cs
public class Program
{
public static void Main(string[] args)
{
IHostBuilder builder = Host.CreateDefaultBuilder(args)
.UseSerilog()
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder.UseStartup();
});
IHost host = builder.Build();
host.Run();
}
}
// BlogContext
using app.Models;
using Microsoft.EntityFrameworkCore;
namespace app.Data
{
public class BlogContext : DbContext
{
public DbSet
Posts { get; set; }
public DbSet Comments { get; set; }
public BlogContext(DbContextOptions options) : base(options)
{
}
}
}
// Startup.cs
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
public string ConnectionString => Configuration.GetConnectionString("Blog");
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext(opt => { opt.UseSqlite(ConnectionString); });
}
}