@page "/" @using System @inject IJSRuntime Js <label>Html Multiple Select, Choosed Item: @(string.Join(",", ChoosedMultipleItem))</label> <br /> <select @ref=RefMultipleSelect multiple @onchange=ChangedMultipleSelect> <option>Turkey</option> <option>Azerbaijan</option> <option>Germany</option> <option>Italy</option> <option>France</option> </select> @code { ElementReference RefMultipleSelect; public IList<string> ChoosedMultipleItem { get; set; } = new List<string>(); async void ChangedMultipleSelect() { ChoosedMultipleItem = await Js.InvokeAsync<IList<string>>("getSelectedValues", new object[] {RefMultipleSelect}); await InvokeAsync(StateHasChanged); } }
namespace BlazorFiddleProject { using Microsoft.AspNetCore.Components.Builder; using Microsoft.Extensions.DependencyInjection; public class Startup { public void ConfigureServices(IServiceCollection services) { } public void Configure(IComponentsApplicationBuilder app) { app.AddComponent<App>("app"); } } }
<!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"> <style> app { } </style> <script type="text/javascript"> </script> </head> <body style="padding: 25px"> <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> window.getSelectedValues = function(sel) { var results = []; var i; for (i = 0; i < sel.options.length; i++) { if (sel.options[i].selected) { results[results.length] = sel.options[i].value; } } return results; }; </script> </body> </html>

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