VB.NET

Clear the FTP Directory Listing Cache

Demonstrates the Chilkat Ftp2.ClearDirCache method, which clears the cached listing for the current remote directory. It takes no arguments; the next indexed-listing call fetches a fresh listing from the server.

Background: The index-based directory API caches the listing the first time you read it, so repeated accessor calls avoid extra round trips. The trade-off is staleness: if the directory changes — files added or removed, whether by your own operations or another process — the cache still reflects the old state. ClearDirCache discards it so the next GetDirCount queries the server again.

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Dim success As Boolean = False

'  Demonstrates the Ftp2.ClearDirCache method, which clears the cached listing for the current
'  remote directory.  It takes no arguments and is a void method.

Dim ftp As New Chilkat.Ftp2

ftp.Hostname = "ftp.example.com"
ftp.Username = "myFtpLogin"

'  Normally you would not hard-code the password in source.  You should instead obtain it
'  from an interactive prompt, environment variable, or a secrets vault.
ftp.Password = "myPassword"

success = ftp.Connect()
If (success = False) Then
    Debug.WriteLine(ftp.LastErrorText)
    Exit Sub
End If


success = ftp.ChangeRemoteDir("public_html")
If (success = False) Then
    Debug.WriteLine(ftp.LastErrorText)
    Exit Sub
End If


'  The first GetDirCount caches the listing.
Dim n As Integer = ftp.GetDirCount()
Debug.WriteLine("Entries: " & n)

'  ... the remote directory changes (files added or removed by another process) ...

'  Discard the cache so the next listing call fetches fresh data from the server.
ftp.ClearDirCache()

n = ftp.GetDirCount()
Debug.WriteLine("Entries after refresh: " & n)

success = ftp.Disconnect()
If (success = False) Then
    Debug.WriteLine(ftp.LastErrorText)
    Exit Sub
End If