Index
@page "/"
@using System.Text.RegularExpressions
<input type="text"
value="@counter"
@oninput="OnInput"
@onkeydown="OnKeyDown"
@onkeypress="OnKeyPress"
@onkeypress:preventDefault="true" />
@code {
private string counter;
private void OnInput(ChangeEventArgs args)
{
counter = args.Value.ToString();
}
private void OnKeyDown(KeyboardEventArgs e)
{
if (e.Key == "Backspace" && counter.Length == 1)
{
counter = " ";
}
}
private void OnKeyPress(KeyboardEventArgs e)
{
if (Regex.IsMatch(e.Key, "[0-9]"))
{
counter += int.Parse($"{e.Key}").ToString();
}
}
}
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>
Add component
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