Passing a WebAPI application from .NET Core 2 to .NET Core 3 in 5 +1 (EF) steps

Simple steps:

1. Modiffy in the .csproj  <TargetFramework>netcoreapp2.0</TargetFramework> to <TargetFramework>netcoreapp3.1</TargetFramework> 

2.Delete <PackageReference Include=”Microsoft.AspNetCore.All” Version=”2.0.8″ />

3. Modify

public static IWebHost BuildWebHost(string[] args) =>
public static IHostBuilder CreateHostBuilder(string[] args) =>

WebHost.CreateDefaultBuilder(args)
Host.CreateDefaultBuilder(args)

.UseStartup<Startup>()
.ConfigureWebHostDefaults(webBuilder =>

.Build();

to

public static IHostBuilder CreateHostBuilder(string[] args) =>

WebHost.CreateDefaultBuilder(args)
Host.CreateDefaultBuilder(args)

.UseStartup<Startup>()
.ConfigureWebHostDefaults(webBuilder =>

.Build();
{

webBuilder.UseStartup<Startup>();

});

3.  Modify BuildWebHost(args).Run();  to CreateHostBuilder(args).Build().Run();

4. Modify services.AddMvc();   to

services.AddControllers();

services.AddRouting();

5. Modify  app.UseMvc();  to

app.UseRouting();

app.UseEndpoints(endpoints =>

{

endpoints.MapControllers();

});

6. Optional : modify EF from

<PackageReference Include=”Microsoft.EntityFrameworkCore.SqlServer” Version=”2.1.1″ />
<PackageReference Include=”Microsoft.EntityFrameworkCore.SqlServer” Version=”3.1.3″ />

<PackageReference Include=”Microsoft.EntityFrameworkCore.Tools” Version=”2.1.1″ />
<PackageReference Include=”Microsoft.EntityFrameworkCore.Tools” Version=”3.1.3″>

<PackageReference Include=”Microsoft.VisualStudio.Web.CodeGeneration.Design” Version=”2.1.1″ />

to

<PackageReference Include=”Microsoft.EntityFrameworkCore.SqlServer” Version=”3.1.3″ />

<PackageReference Include=”Microsoft.EntityFrameworkCore.Tools” Version=”2.1.1″ />
<PackageReference Include=”Microsoft.EntityFrameworkCore.Tools” Version=”3.1.3″>

<PackageReference Include=”Microsoft.VisualStudio.Web.CodeGeneration.Design” Version=”2.1.1″ />
<PrivateAssets>all</PrivateAssets>

<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

</PackageReference>

<PackageReference Include=”Microsoft.VisualStudio.Web.CodeGeneration.Design” Version=”3.1.2″