VerifyReCaptcha

.VerifyReCapture(HttpContext context, string secretKey)

Validates the Google ReCapture 2.

First go to https://www.google.com/recaptcha/admin and create a site and secret key. Include "localhost" for debugging.

Razor

On the Razor page add the following

@using Microsoft.Extensions.Configuration
@inject IConfiguration config

<div class="col-md-12">
<div class="g-recaptcha" data-sitekey="@(config.GetValue<string>("ReCaptcha:SiteKey"))"></div>
</div>


@section Scripts {
<script src="https://www.google.com/recaptcha/api.js"></script>
<script src="https://www.google.com/recaptcha/api.js?onload=onloadCallback&render=explicit" async defer></script>
}

C#

public IActionResult MyView()
{
if (SiUtil.VerifyCaptcha(HttpContext, _config.GetValue<string>("ReCaptcha:SecretKey")))
{
... do your work
}
}