@page "/" <MatSelect Outlined="true" Label="Category" ValueChanged="(string i)=>OnChangeCategory(i)"> <MatOptionString></MatOptionString> @foreach (var cat in GetCategories()) { <MatOptionString Value="@cat">@cat</MatOptionString> } </MatSelect> <MatSelect Outlined="true" Label="Product" @bind-Value="@Product" > <MatOptionString></MatOptionString> @foreach (var prod in GetProducts(Category)) { <MatOptionString Value="@prod">@prod</MatOptionString> } </MatSelect> @code { protected string Category {set; get;} = ""; protected string Product {set; get;} = ""; protected async Task OnChangeCategory(string newValue) { this.Category = newValue; // call background tasks await Task.CompletedTask; } protected IEnumerable<string> GetCategories() { return new List<string>() { "one", "two", "three" }; } protected IEnumerable<string> GetProducts(string category) { return (new List<string>() { "one", "two", "three" }).Select(x=>$"{category}-{x}" ); } }
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"> <script src="_content/MatBlazor/dist/matBlazor.js"></script> <style> app { } </style> <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> </body> </html>

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