How do you create a dropdownlist from an enum in ASP.NET MVC? In the following example, the default behavior is prevented by specifying the @onkeydown:preventDefault directive attribute. This ensures that the reference variable is assigned before the event handler is assigned. If using the .NET CLI to add the package reference, include the --prerelease option when you execute the dotnet add package command. For additional information, see Blazor Two Way Binding Error (dotnet/aspnetcore #24599). The site loads fast thanks to static prerendering using the community-maintained BlazorWasmPrerendering.Build GitHub project. Consider the following example. Specify delegate event handlers in Razor component markup with @on{DOM EVENT}="{DELEGATE}" Razor syntax:. Razor Pages handler methods facilitate the clear separation of processing code based on user actions on the page without resorting to a confusing pile of conditional code to determine which button was clicked. Supported EventArgs are shown in the following table. ComponentBase implements the lowest abstraction of components, the IComponent interface. To register a root component as a custom element in a Blazor Server app, modify the call to AddServerSideBlazor in Program.cs. In the preceding example: Alternatively, use a foreach loop with Enumerable.Range, which doesn't suffer from the preceding problem: A common scenario with nested components executes a parent component's method when a child component event occurs. Supply the event arguments data using the custom logic stated: In JavaScript, event names don't have a prefix. See also. Custom elements don't support child content or templated components. Specifying the @on{DOM EVENT}:preventDefault attribute without a value is equivalent to @on{DOM EVENT}:preventDefault="true". A component's UI is defined using Razor syntax, which consists of Razor markup, C#, and HTML. Register the custom event with the preceding handler in wwwroot/index.html (Blazor WebAssembly) or Pages/_Layout.cshtml (Blazor Server) immediately after the Blazor
