This article explains how to update an existing ASP.NET Core 3.1 project to ASP.NET Core 6.0. To upgrade from ASP.NET Core 5.0 to 6.0, see <xref:migration/50-to-60>.
If you rely upon a [`global.json`](/dotnet/core/tools/global-json) file to target a specific .NET SDK version, update the `version` property to the .NET 6.0 SDK version that's installed. For example:
```diff
{
"sdk": {
- "version": "3.1.200"
+ "version": "6.0.100"
}
}
```
<aname="tf"></a>
## Update the target framework
Update the project file's [Target Framework Moniker (TFM)](/dotnet/standard/frameworks) to `net6.0`:
In the project file, update each [`Microsoft.AspNetCore.*`](https://www.nuget.org/packages?q=Microsoft.AspNetCore.%2A), [`Microsoft.EntityFrameworkCore.*`](https://www.nuget.org/packages?q=Microsoft.EntityFrameworkCore.%2A), [`Microsoft.Extensions.*`](https://www.nuget.org/packages?q=Microsoft.Extensions.%2A), and [`System.Net.Http.Json`](https://www.nuget.org/packages/System.Net.Http.Json) package reference's `Version` attribute to 6.0.0 or later. For example:
The ASP.NET Core templates generate code using the new [minimal hosting model](xref:migration/50-to-60#new-hosting-model). The minimal hosting model unifies `Startup.cs` and `Program.cs` into a single `Program.cs` file. `ConfigureServices` and `Configure` are no longer used. Apps migrating from ASP.NET Core 3.1 to 6.0 don't need to use the minimal hosting model, using `Startup` and the [Generic Host](xref:fundamentals/host/generic-host) used by the ASP.NET Core 3.1 templates is fully supported.
To use `Startup` with the new minimal hosting model, see [Use Startup with the new minimal hosting model](xref:migration/50-to-60#smhm).
To migrate to the new minimal hosting model using the following pattern used by the ASP.NET Core 6.0 templates, see [
Code samples migrated to the new minimal hosting model in ASP.NET Core 6.0](xref:migration/50-to-60-samples) and [Migrate from ASP.NET Core 5.0 to 6.0](xref:migration/50-to-60)
To adopt all of the [5.0 features](xref:aspnetcore-5.0) and [6.0 features](xref:aspnetcore-6.0#blazor) for Blazor apps, we recommend the following process:
* Create a new 6.0 Blazor project from one of the Blazor project templates. For more information, see <xref:blazor/tooling>.
* Move the app's components and code to the 6.0 app making modifications to adopt the new 5.0 and 6.0 features.
## Update Docker images
For apps using Docker, update your *Dockerfile*`FROM` statements and scripts. Use a base image that includes the ASP.NET Core 6.0 runtime. Consider the following `docker pull` command difference between ASP.NET Core 3.1 and 6.0:
As part of the move to ".NET" as the product name, the Docker images moved from the `mcr.microsoft.com/dotnet/core` repositories to `mcr.microsoft.com/dotnet`. For more information, see [.NET 5.0 - Docker Repo Name Change (dotnet/dotnet-docker #1939)](https://github.com/dotnet/dotnet-docker/issues/1939).
In ASP.NET Core 3.1 and earlier, `DateTime` values were model-bound as local time, where the timezone was determined by the server. `DateTime` values bound from input formatting (JSON) and `DateTimeOffset` values were bound as UTC timezones.
In ASP.NET Core 5.0 and later, model binding consistently binds `DateTime` values with the UTC timezone.
To retain the previous behavior, remove the `DateTimeModelBinderProvider` in `Startup.ConfigureServices`:
To add support for model binding [C# 9 record types](/dotnet/csharp/whats-new/csharp-9#record-types), the <xref:Microsoft.AspNetCore.Mvc.ModelBinding.Binders.ComplexTypeModelBinderProvider> is:
* Annotated as obsolete.
* No longer registered by default.
Apps that rely on the presence of the `ComplexTypeModelBinderProvider` in the `ModelBinderProviders` collection need to reference the new binder provider:
```diff
- var complexModelBinderProvider = options.ModelBinderProviders.OfType<ComplexTypeModelBinderProvider>();
+ var complexModelBinderProvider = options.ModelBinderProviders.OfType<ComplexObjectModelBinderProvider>();
The ASP.NET Core 3.1 templates that include an option for individual user accounts generate a call to <xref:Microsoft.AspNetCore.Builder.DatabaseErrorPageExtensions.UseDatabaseErrorPage%2A>. `UseDatabaseErrorPage` is now obsolete and should be replaced with a combination of `AddDatabaseDeveloperPageExceptionFilter` and `UseMigrationsEndPoint`, as shown in the following code:
```diff
public void ConfigureServices(IServiceCollection services)
* [Identity: Default Bootstrap version of UI changed](/dotnet/core/compatibility/aspnet-core/6.0/identity-bootstrap4-to-5)
* [Breaking changes for migration from version 3.1 to 5.0](/dotnet/core/compatibility/3.1-5.0). ASP.NET Core and Entity Framework Core are also included in the list.
* [Breaking changes for migration from version 5.0 to 6.0](/dotnet/core/compatibility/6.0): Includes ASP.NET Core and Entity Framework Core.
* [Announcements GitHub repository (aspnet/Announcements, `6.0.0` label)](https://github.com/aspnet/Announcements/issues?q=is%3Aissue+label%3A6.0.0+is%3Aopen): Includes breaking and non-breaking information.
