EF Core从5升级至9后IIS应用池回收时触发DbContext未配置异常的问题求助

阿华AIGC实验室

2026-4-14

我们团队在多个业务系统里使用EF Core 5已经有相当长一段时间了，之前一直因为依赖关系的牵绊没敢升级。这次好不容易完成了版本升级，本地在Visual Studio里测试完全没问题，部署到IIS上初期也一切正常——网站能正常访问，数据库连接也没问题。

可一旦IIS回收了应用池，麻烦就来了，系统会直接抛出InvalidOperationException异常，具体信息如下：

System.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 object in its constructor and passes it to the base constructor for DbContext.
at Microsoft.EntityFrameworkCore.Internal.DbContextServices.Initialize(IServiceProvider scopedProvider, DbContextOptions contextOptions, DbContext context)
at Microsoft.EntityFrameworkCore.DbContext.get_ContextServices()
at Microsoft.EntityFrameworkCore.DbContext.get_Model()
at Microsoft.EntityFrameworkCore.Internal.InternalDbSet1.get_EntityType() at Microsoft.EntityFrameworkCore.Internal.InternalDbSet1.CheckState()
at Microsoft.EntityFrameworkCore.Internal.InternalDbSet1.get_EntityQueryable() at Microsoft.EntityFrameworkCore.Internal.InternalDbSet1.System.Collections.Generic.IAsyncEnumerable.GetAsyncEnumerator(CancellationToken cancellationToken)
at System.Runtime.CompilerServices.ConfiguredCancelableAsyncEnumerable1.GetAsyncEnumerator() at Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions.ToListAsync[TSource](IQueryable1 source, CancellationToken cancellationToken)
at Beheer.Services.Dashboard.DashboardService.GetMaxDaysFromSettings() in D:\Agents\Agent.Morpheus_work\2\s\Back-end\Beheer.Services\Dashboard\DashboardService.cs:line 330
at Beheer.Services.Dashboard.DashboardService.GetRecentErrorLogs(Paging paging) in D:\Agents\Agent.Morpheus_work\2\s\Back-end\Beheer.Services\Dashboard\DashboardService.cs:line 137
at Beheer.Api.Controllers.DashboardController.GetRecentErrorLogs(Paging paging) in D:\Agents\Agent.Morpheus_work\2\s\Back-end\Beheer.Api\Controllers\DashboardController.cs:line 99
at lambda_method62(Closure, Object)
at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.AwaitableObjectResultExecutor.Execute(ActionContext actionContext, IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)

下面是相关的代码片段：

Program类代码

public static class Program
{
    public static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }

    private static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureAppConfiguration((hostingContext, config) =>
                {
                    var env = hostingContext.HostingEnvironment.EnvironmentName;
                    config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);
                    config.AddJsonFile($"appsettings.{env}.json", optional: true, reloadOnChange: true);
                    config.AddEnvironmentVariables();

                    if (args != null)
                    {
                        config.AddCommandLine(args);
                    }
                })
           .ConfigureWebHostDefaults(webBuilder =>
             {
               webBuilder.UseStartup<Startup>();
             })
          .UseSerilog((hostingContext, loggerConfiguration) => loggerConfiguration
                   .ReadFrom.AppSettings().Enrich.FromLogContext());
}

Startup类代码

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)
    {
        var connectionString = Configuration["AppSettings:ConnectionString"];
        services.AddDbContext<MyContext>(options => options.UseOracle(connectionString));
     
        // ....
    }
}

MyContext类代码

public class MyContext : DbContext
{
    public MyContext()
    {
    }

    public MyContext(DbContextOptions<MyContext> options)
        : base(options)
    {
    }

    public virtual DbSet<SenderSettings> SenderSettings { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
    }
}

希望各位大佬能给点下一步排查的方向，非常感谢！

编辑更新：今天终于抽出时间深入排查了，先回复下大家的建议：