@inject IJSRuntime JsRuntime @page "/" <div> <input class="form-control" id="first-text-box" type="text" @ref="TextBoxControl" @bind="_model.Box1" /> </div> <div> <input class="form-control" id="second-text-box" type="text" @bind="_model.Box2" /> </div> @code { private ElementReference TextBoxControl { get; set; } private readonly BoxClass _model = new BoxClass(); protected override async Task OnAfterRenderAsync(bool firstRender) { await JsRuntime.InvokeVoidAsync("jsFunctions.focusElement", TextBoxControl); await base.OnAfterRenderAsync(firstRender); } }
namespace BlazorFiddleProject { using System; using Microsoft.AspNetCore.Components.Builder; using Microsoft.Extensions.DependencyInjection; using Microsoft.AspNetCore.Components; public class Startup { public void ConfigureServices(IServiceCollection services) { } public void Configure(IComponentsApplicationBuilder app) { app.AddComponent<App>("app"); } } public class BoxClass { public string Box1 {get;set;} public string Box2 {get;set;} } }
<!DOCTYPE html> <html> <head> <meta charset="utf-8"/> <meta name="viewport" content="width=device-width"> <title>BlazorFiddleProject</title> <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous"> <script src="_content/MatBlazor/dist/matBlazor.js"></script> <script type="text/javascript"> </script> </head> <body> <app>Loading...</app> <script src="_framework/blazor.webassembly.js"></script> <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script> <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script> <script type="text/javascript"> window.jsFunctions = { focusElement: function(element) { element.focus(); } }; </script> </body> </html>

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