ASP.NET Core 3.0 not showing on Visual Studio 2019

asp.net-core .net-core visual-studio-2019 .net-core-3.0 asp.net-core-3.0
Guilherme picture Guilherme · Mar 6, 2019 · Viewed 70.1k times · Source

I want to test the new Blazor server-side framework (aka Razor Components).

I installed Visual Studio 2019 RC, and then the .Net Core 3.0 preview 2, following this official tutorial.

After the install, I only see the ASP.NET Core 2.0 and the 2.1 on the "Create a new ASP.NET Core Web Application" page. The 3.0 is not showing up.

I started to mess around, trying to install other packages from this page, uninstalled and reinstalled Visual Studio 2019, updated to the .NET Core Preview 3, installed several times the x64 and x86 packages in different orders, copy/paste the .Net Core binaries to random folders and so on. Nothing works. The ASP.NET Core 3.0 does not show up.

Here is what my VS looks like when creating a project (the yellow message appeared latter after some messing around with the packages, so it is not the real problem):

enter image description here

Here is the output of the dotnet --list-sdks command:

enter image description here

EDIT

For some reason, I installed the Blazor VSIX package (the WebAssembly - not exactly what I want, but I installed it anyways) and now the ASP.NET Core 3.0 simply shows up. However, just for the blazor templates:

enter image description here

I don't understand. Is there anything obvious I'm missing?

Answer

Jimmy picture Jimmy · Mar 7, 2019

There is an option in Tools -> Options that enables preview versions of the .NET Core SDK. In the VS Preview shipping channel, it is on (by default, and not settable). In the VS Release channel, it defaults to off and you can opt-in.

"Use Previews of the .NET Core SDK" in the Tools->Options dialog

(Note: it's disabled in the screenshot because I have a Preview build installed.)

The reason for this is to allow you to customize whether a project using a released version of .NET Core (such as 2.1, the current LTS) will use tooling from the newer not-yet-release-quality SDK.

Prior to 16.1, this option was located on the Tools -> Options -> Projects and Solutions -> .NET Core page.

Related questions

AddTransient, AddScoped and AddSingleton Services Differences

I want to implement dependency injection (DI) in ASP.NET Core. So after adding this code to ConfigureServices method, both ways work. What is the difference between the services.AddTransient and service.AddScoped methods in ASP.NET Core? public void …

Read More
How to read AppSettings values from a .json file in ASP.NET Core

I have set up my AppSettings data in file appsettings/Config .json like this: { "AppSettings": { "token": "1234" } } I have searched online on how to read AppSettings values from .json file, but I could not get anything useful. I tried: var configuration = …

Read More
How to determine if .NET Core is installed

I know that for older versions of .NET, you can determine if a given version is installed by following https://support.microsoft.com/en-us/kb/318785 Is there an official method of determining if .NET Core is installed? (And I don't …

Read More