(C# UWP/WinRT) Delete Local Files that Do Not Exist on the FTP Server

Demonstrates how to get a list of local files in a directory tree that do not exist on the FTP server.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Ftp2 ftp = new Chilkat.Ftp2();

ftp.Hostname = "ftp.example.com";
ftp.Username = "login";
ftp.Password = "password";

ftp.KeepSessionLog = true;

// Connect and login to the FTP server.
bool success = await ftp.ConnectAsync();
if (success != true) {
    Debug.WriteLine(ftp.LastErrorText);
    return;
}

// Set the current remote directory to the root of
// the remote tree to be compared.
success = await ftp.ChangeRemoteDirAsync("abc123");
if (success != true) {
    Debug.WriteLine(ftp.LastErrorText);
    return;
}

// Recursively descend the local directory tree
// and find the files that exist locally but not remotely.
// These are the files what would be uploaded via
// the SyncRemoteTree method call with mode = 1.
// (Mode 1 would upload all files that do not exist on the FTP server.)

// The actual uploading is avoided by setting the preview-only argument to true.
int mode = 1;
bool descendTree = true;
bool previewOnly = true;
success = await ftp.SyncRemoteTree2Async("/temp/abc123",mode,descendTree,previewOnly);
if (success != true) {
    Debug.WriteLine(ftp.LastErrorText);
    return;
}

// The files what would've been uploaded are now available in the SyncPreview property,
// which contains a list of local file paths, one per line.
// A program can iterate over them like this:
Chilkat.StringArray sa = new Chilkat.StringArray();
sa.LoadFromText(ftp.SyncPreview);

Chilkat.FileAccess fac = new Chilkat.FileAccess();

int numFiles = sa.Count;
int i = 0;
string localFilePath;
while ((i < numFiles)) {
    localFilePath = sa.GetString(i);
    Debug.WriteLine(localFilePath);

    // An application can delete the file using Chilkat's file access object,
    // or it can choose to use the native file API available in the programming language:
    success = fac.FileDelete(localFilePath);
    if (success != true) {
        Debug.WriteLine("Failed to delete: " + localFilePath);
    }

    i = i + 1;
}

success = await ftp.DisconnectAsync();