If the value is true, the property is set. Side effects are minimized. To support the assignment of a composed value, use a method, field, or property. Unique identifiers. Experimental support is available for building custom elements using the Microsoft.AspNetCore.Components.CustomElements NuGet package. {PROJECT ROOT} is the app's project root. The following ParameterParent component renders two ParameterChild components: The following rendered HTML markup from the ParameterParent component shows ParameterChild component default values when the ParameterParent component doesn't supply component parameter values. For more information, see the following resources: EventArgs classes in the ASP.NET Core reference source (dotnet/aspnetcore main branch). Routing in Blazor is achieved by providing a route template to each accessible component in the app with an @page directive. How Can I Connect my code from Program.cs to My Razor Page Button? the button event is fired, the postback occurs ; this is not the aspnet_regiis. The demo site is built using Blazor WebAssembly and is hosted on GitHub Pages. Experimental features are provided for the purpose of exploring feature viability and may not ship in a stable version. To expose events across components, use an EventCallback. Access the data that was passed in from JavaScript in the delegate handler method: If the @oncustomevent attribute isn't recognized by IntelliSense, make sure that the component or the _Imports.razor file contains an @using statement for the namespace containing the EventHandler class. In JavaScript, define a function for building the custom event argument object from the source event: Register the custom event with the preceding handler in wwwroot/index.html (Blazor WebAssembly) or Pages/_Host.cshtml (Blazor Server) immediately after the Blazor