How to import Microsoft.AspNetCore.Hosting.IWebHostEnvironment?

Question

The following code in my project gets the following error.

public static IServiceCollection AddInfrastructure(this IServiceCollection services, 
  IConfiguration configuration, 
  Microsoft.AspNetCore.Hosting.IWebHostEnvironment environment) // Error
{
    //    .....
    return services;
}

Error CS0234 The type or namespace name 'IWebHostEnvironment' does not exist in the namespace 'Microsoft.AspNetCore.Hosting' (are you missing an assembly reference?)

I already import the nuget package.

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.Hosting" Version="2.2.7" />
    <PackageReference Include="Microsoft.AspNetCore.Hosting.Abstractions" Version="2.2.0" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="3.0.0" />
  </ItemGroup>

Answer 1

If you want to use Microsoft.AspNetCore.Hosting.IWebHostEnvironment in a separate library project other than your web project, you have to explicitly add the Microsoft.AspNetCore.App package reference to the library project by editing the project file.

In Dotnet 5.0 also, we have to follow same approach.

<Project SDK="Microsoft.NET.Sdk">

 <PropertyGroup>
  <OutputType>Library</OutputType>
  <TargetFramework>net5.0</TargetFramework>
 </PropertyGroup>

 <ItemGroup>
  <FrameworkReference Include="Microsoft.AspNetCore.App" />
 </ItemGroup>

 <ItemGroup>...</ItemGroup>

</Project>