Adding reCAPTCHA to a .NET Core Web Site

• reCAPTCHA v2 | Google Developers
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• Adding reCAPTCHA to a .NET Core Web Site | by Dmitry Danov | Medium
• How to Add Google reCAPTCHA to Your Website | ZULWeb

Signing up for reCAPTCHA can be done here: https://www.google.com/recaptcha/about/. Once signed up, you will be guided through creating a new site (reCAPTCHA v2).

In the following steps, we will need both a reCAPTCHA Site Key and Secret Key. Bot keys are found on the settings screen on the new site:

reCAPTCHA is added by including the JavaScript from Google somewhere. For ASP.NET Core add it to the Scripts section:

@section Scripts {
<script src="https://www.google.com/recaptcha/api.js" async defer></script>
<partial name="_ValidationScriptsPartial" />
</script>

Next, you will need to tell reCAPTCHA where to put the CAPTCHA control. Paste the following markup inside the form element:

<div class="form-group">
<div class="g-recaptcha" data-sitekey="SITE_KEY"></div>
</div>

For the data-sitekey attribute, use the reCAPTCHA site key from the site settings.

• How to Fix the “Error for Site Owner: Invalid Key Type” Issue (minitool.com)
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