DNTCaptcha.Core is a captcha generator and validator for ASP.NET Core applications.
To install DNTCaptcha.Core, run the following command in the Package Manager Console:
PM> Install-Package DNTCaptcha.Core
You can also view the package page on NuGet.
- After installing the DNTCaptcha.Core package, add the following definition to the _ViewImports.cshtml file:
@addTagHelper *, DNTCaptcha.Core- Then to use it, add its new tag-helper to your view:
<dnt-captcha asp-captcha-generator-max="9000"
asp-captcha-generator-min="1"
asp-captcha-generator-language="English"
asp-placeholder="Security code as a number"
asp-validation-error-message="Please enter the security code as a number."
asp-font-name="Tahoma"
asp-font-size="20"
asp-fore-color="black"
asp-back-color="#ccc"
asp-text-box-class="text-box single-line form-control col-md-4"
asp-text-box-template="<div class='input-group col-md-4'><span class='input-group-addon'><span class='glyphicon glyphicon-lock'></span></span>{0}</div>"
asp-validation-message-class="text-danger"
asp-refresh-button-class="glyphicon glyphicon-refresh btn-sm"
/>- To register its default providers, call
services.AddDNTCaptcha();method in your Startup class.
using DNTCaptcha.Core;
namespace DNTCaptcha.TestWebApp
{
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
services.AddDNTCaptcha();
}- Now you can add the
ValidateDNTCaptchaattribute to your action method to verify the entered security code:
[HttpPost, ValidateAntiForgeryToken]
[ValidateDNTCaptcha(ErrorMessage = "Please enter the security code as a number.",
IsNumericErrorMessage = "The input value should be a number.",
CaptchaGeneratorLanguage = Language.English)]
public IActionResult Index([FromForm]AccountViewModel data)
{
if (ModelState.IsValid)
{
//TODO: Save data
return RedirectToAction(nameof(Thanks), new { name = data.Username });
}
return View();
}- This library uses unobtrusive Ajax library for the refresh button. Make sure you have included its related scripts too:
Please follow the DNTCaptcha.TestWebApp sample for more details.
- To run this project on Linux, you will need to install
libgdiplustoo:
sudo apt-get update
sudo apt-get install libgdiplus