Constructor Dependency Injection in Blazor Components’ partial classes

As of writing this article, till the ASP.NET Core 6.0 preview-2, Blazor components’ partial classes don’t support constructor dependency injection.

But we can easily overcome this limitation by using a small open-source Blazor library called TanvirArjel.Blazor as follows:

First, we have to install the TanvirArjel.Blazor NuGet package as follows:

PMC:

Install-Package TanvirArjel.Blazor

.NET CLI:

dotnet add package TanvirArjel.Blazor

Then for Blazor Server, in the ConfigureServices method of the Startup class:

using TanvirArjel.Blazor.DependencyInjection;
    
services.AddComponents();

For Blazor WebAssembly, in the Main method of Program class:

using TanvirArjel.Blazor.DependencyInjection;
    
builder.Services.AddComponents();

That’s it. Now you can inject the dependencies in your Blazor component partial classes constructor as follows:

public partial class FetchDataComponent 
{
   private readonly WeatherForecastService _forecastService;
         
   public FetchDataComponent(WeatherForecastService forecastService)
   {            
     _forecastService = forecastService;
   }
   private WeatherForecast[] Forecasts { get; set; }
   protected override async Task OnInitializedAsync()
   {            
      Forecasts = await _forecastService.GetForecastAsync(DateTime.Now);        
   }    
}

Happy Software Development!