C#

using System.IO;
using System.Threading.Tasks;

namespace WpfApp1
{
    internal class Sharepoint
    {
        public async Task DownloadFileAsync(string folderName, string downloadPath = null)
        {
            var url = _clientContext.Web.ServerRelativeUrl + "/Shared%20Documents/" + folderName;
            Folder targetFolder = _clientContext.Web.GetFolderByServerRelativeUrl(url);
            _clientContext.Load(targetFolder.Files);

            await _clientContext.ExecuteQueryAsync();

            foreach (var file in targetFolder.Files)
            {
                FileInformation sharepointFile = Microsoft.SharePoint.Client.File.OpenBinaryDirect(_clientContext, file.ServerRelativeUrl);
                await _clientContext.ExecuteQueryAsync();

                var path = string.IsNullOrEmpty(downloadPath) ? DEFAULT_DIRECTORY : downloadPath;
                path = path + @"\" + file.Name;
                using (FileStream filestream = new FileStream(path, FileMode.Create))
                {
                    sharepointFile.Stream.CopyTo(filestream);
                }
            }
        }
    }
}

using System.IO;
using System.Threading.Tasks;

namespace WpfApp1
{
    internal class Repository
    {
        string _appPath;
        Sharepoint _sharePoint;

        public Repository()
        {
            _sharePoint = new Sharepoint();
            _appPath = $"{Path.GetTempPath()}RDSPaymentProcessing";

        }

        public async Task<MyData> GETDataAsync()
        {
            var results = new MyData();

            // If the local file already exists, delete it
            var fileName = $"{Path.GetTempPath()}{LOCAL_APP_DATA_FOLDER}\sharepointdata.xml";
            if (File.Exists(fileName))
            {
                File.Delete(fileName);
            }

            // Download all files from the Settings folder into the local user's app path
            await _sharePoint.DownloadFile(SETINGS_FOLDER, _appPath);

            // If the file was downloaded...
            if (File.Exists(fileName))
            {
                // Deserialize it
                results = Serialization.DeSerializeObject<MyData>(fileName);
            }
            else
            {
                //TODO: Replace with custom exception
                throw new FileNotFoundException(fileName);
            }

            return results;
        }
    }
}

namespace WpfApp1
{
    internal class MainWindowViewModel
    {
        private MyEntity _data;

        /// <summary>
        /// Occurs when the window's Loaded event is callled
        /// </summary>
        public async void WindowLoadedExecuted()
        {
            await _repository.GETDataAsync();
        }
    }
}

[DataMember]
public ServiceArm ServiceArm { get; set; } = ServiceArm.Undefined;

public string ServiceName => Enum.GetName( typeof( ServiceArm ), this.ServiceArm );

block.ServiceArm = Enum.Parse<ServiceArm>( unit.ServiceName );