Sitefinity MVC ReCaptacha

RecaptchaController.cs

using SitefinityWebApp.Mvc.Models;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Web;
using Telerik.Sitefinity.Data.Metadata;
using Telerik.Sitefinity.Frontend.Forms;
using Telerik.Sitefinity.Frontend.Forms.Mvc.Controllers.Base;
using Telerik.Sitefinity.Model;
using Telerik.Sitefinity.Mvc;
using Telerik.Sitefinity.Web.UI.Fields.Enums;

namespace SitefinityWebApp.Mvc.Controllers {
    
    [ControllerToolboxItem(Name = "Recaptcha", Title = "Recaptcha", Toolbox = FormsConstants.FormControlsToolboxName, SectionName = "Common")]
    [DatabaseMapping(UserFriendlyDataType.ShortText)]
    public class RecaptchaController : FormFieldControllerBase<RecaptchaModel> {
        public string SiteKey { get; set; }

        public RecaptchaController() {
            this.DisplayMode = FieldDisplayMode.Write;
        }
        
        public override RecaptchaModel Model {
            get {
                if (this.model == null)
                    this.model = new RecaptchaModel();
                this.model.SiteKey = this.SiteKey;
                return this.model;
            }
        }

        private RecaptchaModel model;
    }
}

RecaptchaModel.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using Telerik.Sitefinity.Frontend.Forms.Mvc.Models.Fields;

namespace SitefinityWebApp.Mvc.Models {
    public class RecaptchaModel : FormFieldModel {
        public string SubmitValue {
            get; set;
        }
        public string SiteKey { get; set; }
        public override object GetViewModel(object value) {
            return base.GetViewModel(value);
        }

        public override object GetViewModel(object value, Telerik.Sitefinity.Metadata.Model.IMetaField metaField) {
            this.Value = value as string ?? (this.MetaField != null ? this.MetaField.DefaultValue : null) ?? string.Empty;
            return this;
        }
    }
}

Write.Default.cshtml

@model SitefinityWebApp.Mvc.Models.RecaptchaModel

@using Telerik.Sitefinity.Frontend.Mvc.Helpers;
@using Telerik.Sitefinity.Modules.Pages;
@using Telerik.Sitefinity.Services;

@Html.Script(ScriptRef.JQuery, "top", false)
@Html.Script("https://www.google.com/recaptcha/api.js", "head", false)

<div class="@Model.CssClass form-group">
    @if (Model.SiteKey.IsNullOrWhitespace())
    {
        @Html.Raw("PLease configure your sitekey")
    }
    else
    {
        <div class="g-recaptcha recaptcha" data-sitekey="@Model.SiteKey" data-callback="onReturnCallback" data-theme="light"></div>
    }
</div>
<script type="text/javascript">
    $(document).ready(function () {

        var captchaForm = $('.g-recaptcha').parents('form').first();
        captchaForm.submit(function (e) {
            debugger;
            var response = grecaptcha.getResponse();
            if (response.length == 0) {
                //reCaptcha not verified
                e.preventDefault();
                grecaptcha.reset();
            }
        });

    });

    function onReturnCallback() {
        $(".sf-fieldWrp button").removeAttr("disabled");
    }
</script>