Download sharepoint 2013 file using sharepoint 2013 client dll (Sharepoint 2013 Web service)

using (var clientContext = new Microsoft.SharePoint.Client.ClientContext(textBox_URL.Text))
{
clientContext.Credentials = new NetworkCredential(textBox_ID.Text, textBox_PW.Text);//Sharepoint 2013 access ID and Password
var list = clientContext.Web.Lists.GetByTitle(titleName);//Library title name
var listItem = list.GetItemById(item.SubItems[0].Text.ToString());//Library document ID
clientContext.Load(list);
clientContext.Load(listItem, i => i.File);
clientContext.ExecuteQuery();

var fileRef = listItem.File.ServerRelativeUrl;
var fileInfo = Microsoft.SharePoint.Client.File.OpenBinaryDirect(clientContext, fileRef);
var fileName = listItem.File.Name;

string serverSubPath = fileRef.Remove(fileRef.Length - fileName.Length);
string localSubPath = label_SelectDownloadFolder.Text + serverSubPath.Replace("/", "\\");
bool exists = System.IO.Directory.Exists(localSubPath);

if (!exists)
{
System.IO.Directory.CreateDirectory(localSubPath);
}

var createFile = Path.Combine(localSubPath, (string)fileName);
using (var fileStream = System.IO.File.Create(createFile))
{
fileInfo.Stream.CopyTo(fileStream);//Create file from sharepoint 2013 using web service
}
}