---
uid: Uno.Development.SignalR
---

# SignalR

[SignalR](https://learn.microsoft.com/aspnet/core/signalr/introduction?view=aspnetcore-7.0) is an ASP.NET Core library that allows server-side code to be instantly pushed to the client.

## Prerequisites

- Visual Studio 2019 or higher
- Azure account (to publish SignalR service)

## Steps

1. Create `ASP.NET Core web application` in Visual Studio and name it `UnoChat.Service`.

    ![project-template](Assets/project-structure.JPG)

2. Add [SignalR Hub](https://learn.microsoft.com/aspnet/core/tutorials/signalr?view=aspnetcore-7.0&tabs=visual-studio#create-a-signalr-hub) to your `[YourProjectName].Service` project in a `Hubs` folder.

3. In your `Startup.cs` file, add your `SignalR` service and a `CORS policy` to the `ConfigureServices` method.

    ```csharp
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddRazorPages();
        services.AddSignalR();
        
        services.AddCors(o => o.AddPolicy(
            "CorsPolicy",
            builder => builder
                .AllowAnyOrigin()
                .AllowAnyMethod()
                .AllowAnyHeader()
        ));
    }
    ```

4. In your `Configure` method, add your CORS policy and `Hubs` endpoint

    ```csharp
    app.UseCors("CorsPolicy");

    app.UseEndpoints(endpoints =>
    {
        endpoints.MapRazorPages();
        endpoints.MapHub<Hubs.[YourProjectHub]>("/yourProjectHub");
    });
    ```

You now have a SignalR service that you can use with your Uno application!