' set up request...
Dim clsRequest As System.Net.FtpWebRequest = _
    DirectCast(System.Net.WebRequest.Create("ftp://ftp.myserver.com/test.txt"),System.Net.FtpWebRequest)
clsRequest.Credentials = New System.Net.NetworkCredential("myusername","mypassword")
clsRequest.Method = System.Net.WebRequestMethods.Ftp.UploadFile

' read in file...
Dim bFile() As Byte = System.IO.File.ReadAllBytes("C:\Temp\test.txt")

' upload file...
Dim clsStream As System.IO.Stream = _
    clsRequest.GetRequestStream()
clsStream.Write(bFile,bFile.Length)
clsStream.Close()
clsStream.Dispose()

我想知道,如果文件已存在于ftp目录中,该文件是否会被覆盖？