Sitecore 9 Forms Encrypted Field Save Action

SaveDataWithEncryption.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
using Sample.Foundation.Core.Helpers;
using Sitecore.Diagnostics;
using Sitecore.ExperienceForms.Data;
using Sitecore.ExperienceForms.Data.Entities;
using Sitecore.ExperienceForms.Models;
using Sitecore.ExperienceForms.Processing;
using Sitecore.ExperienceForms.Processing.Actions;

namespace Sample.Feature.Forms.Actions
{
    public class SaveDataWithEncryption : SaveData
    {
        private IFormDataProvider _dataProvider;        

        public SaveDataWithEncryption(ISubmitActionData submitActionData) : base(submitActionData)
        {
        }

        internal SaveDataWithEncryption(ISubmitActionData submitActionData, IFormDataProvider dataProvider)
            : this(submitActionData)
        {
            Assert.ArgumentNotNull((object)dataProvider, nameof(dataProvider));
            _dataProvider = dataProvider;
        }

        protected override bool TryParse(string value, out string target)
        {
            target = string.Empty;
            return true;
        }

        protected override bool Execute(string data, FormSubmitContext formSubmitContext)
        {
            Assert.ArgumentNotNull((object)formSubmitContext, nameof(formSubmitContext));
            return SavePostedData(formSubmitContext.FormId, formSubmitContext.SessionId, formSubmitContext.Fields);
        }

        protected override bool SavePostedData(
            Guid formId,
            Guid sessionId,
            IList<IViewModel> postedFields)
        {
            try
            {
                FormEntry formEntry = new FormEntry()
                {
                    Created = DateTime.UtcNow,
                    FormItemId = formId,
                    FormEntryId = sessionId,
                    Fields = (ICollection<FieldData>)new List<FieldData>()
                };
                if (postedFields != null)
                {
                    foreach (IViewModel postedField in (IEnumerable<IViewModel>)postedFields)
                        SaveDataWithEncryption.AddFieldData(postedField, formEntry);
                }
                FormDataProvider.CreateEntry(formEntry);
                return true;
            }
            catch (Exception ex)
            {
                Logger.LogError(ex.Message, ex, (object)this);
                return false;
            }
        }

        protected static new void AddFieldData(IViewModel postedField, FormEntry formEntry)
        {
            Assert.ArgumentNotNull((object)postedField, nameof(postedField));
            Assert.ArgumentNotNull((object)formEntry, nameof(formEntry));
            if (!(postedField is IValueField valueField) || !valueField.AllowSave)
                return;
            PropertyInfo property = postedField.GetType().GetProperty("Value");
            object postedValue = (object)property != null ? property.GetValue((object)postedField) : (object)null;
            if (postedValue == null)
                return;
            string fullName = postedValue.GetType().FullName;
            string reflectedTypeName = property.ReflectedType.FullName;
            string fieldValue = ParseFieldValue(postedValue);
            FieldData fieldData = new FieldData
            {
                FieldDataId = Guid.NewGuid(),
                FieldItemId = Guid.Parse(postedField.ItemId),
                FieldName = postedField.Name,
                FormEntryId = formEntry.FormEntryId,
                ValueType = fullName,
                Value = reflectedTypeName == Constants.FormFields.SingleLineTextEncryptedFieldType
                    ? string.IsNullOrWhiteSpace(fieldValue) ? fieldValue : EncryptFieldValue(fieldValue)
                    : fieldValue
            };

            formEntry.Fields.Add(fieldData);
        }

        protected static new string ParseFieldValue(object postedValue)
        {
            Assert.ArgumentNotNull(postedValue, nameof(postedValue));
            List<string> stringList = new List<string>();
            if (postedValue is IList list)
            {
                foreach (object obj in (IEnumerable)list)
                    stringList.Add(obj.ToString());
            }
            else
                stringList.Add(postedValue.ToString());

            return string.Join(",", (IEnumerable<string>)stringList);
        }

        private static string EncryptFieldValue(string valueToEncrypt)
        {
            try
            {
                if (string.IsNullOrWhiteSpace(valueToEncrypt))
                {
                    Log.Error($"{Constants.Logging.LogPreText}Empty or null string passed to {nameof(EncryptFieldValue)}.\r\n\tOriginal (un-encrypted) value will be stored.", new Exception(), typeof(SaveDataWithEncryption));
                    return string.Empty;
                }

                /*
                 * YOUR ENCRYPTION LOGIC GOES HERE
                 */
            }
            catch (Exception ex)
            {
                Log.Error($"{Constants.Logging.LogPreText}An error occurred encrypting the string.\r\n\tOriginal (un-encrypted) value will be stored.", ex, typeof(SaveDataWithEncryption));
                return valueToEncrypt;
            }
        }
    }
}