Blazorators: The Source Generated speechRecognition JavaScript Interop library for Blazor WebAssembly

The Blazor.SpeechRecognition.WebAssembly package consumes the Blazor.SourceGenerators package. It exposes a source generated ISpeechRecognition interface specific to Blazor WebAssembly and the speechRecognition Web API.

Get started

After the NuGet package is added as a reference, call the AddSpeechRecognitionServices method to register the ISpeechRecognitionService type.

using Microsoft.AspNetCore.Components.Web; using Microsoft.AspNetCore.Components.WebAssembly.Hosting; var builder = WebAssemblyHostBuilder.CreateDefault(args); builder.RootComponents.Add<App>("#app"); builder.RootComponents.Add<HeadOutlet>("head::after"); builder.Services.AddScoped( sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) }); builder.Services.AddSpeechRecognitionServices(); await builder.Build().RunAsync();

Anywhere needed within your Razor component, or Blazor client code — either @inject or [Inject] the ISpeechRecognitionService type. The interface takes the following shape:

namespace Microsoft.JSInterop; /// <summary> /// A service the exposes various JavaScript interop capabilities specific to the /// <c>speechRecognition</c> APIs. See <a href="https://developer.mozilla.org/docs/Web/API/SpeechRecognition"></a> /// </summary> public interface ISpeechRecognitionService : IAsyncDisposable { /// <summary> /// Call once, before using in the consuming components /// <c>OnAfterRenderAsync(bool firstRender)</c> override, when firstRender is <c>true</c>. /// </summary> Task InitializeModuleAsync(); /// <summary> /// Cancels the active speech recognition session. /// </summary> /// <param name="isAborted"> /// Is aborted controls which API to call, /// either <c>speechRecognition.stop</c> or <c>speechRecognition.abort</c>. /// </param> void CancelSpeechRecognition(bool isAborted); /// <summary> /// Starts the speech recognition process. Returns an <see cref="IDisposable"/> /// that acts as the subscription. The various callbacks are invoked as they occur, /// and will continue to fire until the subscription is disposed of. /// </summary> /// <param name="language">The BCP47 language tag.</param> /// <param name="onRecognized">The callback to invoke when <c>onrecognized</c> fires.</param> /// <param name="onError">The optional callback to invoke when <c>onerror</c> fires.</param> /// <param name="onStarted">The optional callback to invoke when <c>onstarted</c> fires.</param> /// <param name="onEnded">The optional callback to invoke when <c>onended</c> fires.</param> /// <returns> /// To unsubscribe from the speech recognition, call /// <see cref="IDisposable.Dispose"/>. /// </returns> IDisposable RecognizeSpeech( string language, Action<string> onRecognized, Action<SpeechRecognitionErrorEvent>? onError = null, Action? onStarted = null, Action? onEnded = null); }