@page "/" @inject IJSRuntime JsRuntime <select id="my-select-box" @bind-value="MyValue" @bind-value:event="onchange"> <option value="0">-- Select Something --</option> <option value="1">Option 1</option> <option value="2">Option 2</option> <option value="3">Option 3</option> </select> <br /> @if (MyValue == "0") { <div>Select an option</div> } else { <div>You chose @MyValue</div> } <div style="margin-top: 20px"> <button @onclick="@(() => SelectOptionThroughJs("1"))">Select Option 1</button> <button @onclick="@(() => SelectOptionThroughJs("2"))">Select Option 2</button> <button @onclick="@(() => SelectOptionThroughJs("3"))">Select Option 3</button> </div> @code { public string MyValue {get;set;} = "0"; public async Task SelectOptionThroughJs(string option) { await JsRuntime.InvokeVoidAsync("helperFunctions.selectOption", option); } }
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> <script type="text/javascript"> window.helperFunctions = { selectOption: function(op) { var selectBoxElement = document.getElementById("my-select-box"); selectBoxElement.value = op; } } </script> </body> </html>

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