System.Net.FtpWebRequest tmpReq = (System.Net.FtpWebRequest)System.Net.FtpWebRequest.Create("ftp://domain.com/file.txt");
tmpReq.Credentials = new System.Net.NetworkCredential("userName", "Password");
using (System.Net.WebResponse tmpRes = tmpReq.GetResponse())
{
using (System.IO.Stream tmpStream = tmpRes.GetResponseStream())
{
using (System.IO.TextReader tmpReader = new System.IO.StreamReader(tmpStream))
{
textBox1.Text = tmpReader.ReadToEnd();
}
}
}