Table of Contents

Files and folders

Once connected, TTMSFNCCloudBox browses the account's files and folders. Every request is asynchronous: you call a method, the component performs the HTTP request in the background, and the result arrives in a completion event carrying a TTMSFNCCloudBaseRequestResult. This chapter covers listing folders, reading item metadata, and the event-driven result model you will use throughout the component.

The async result model

No Box method blocks waiting for the network. Each one has a matching On... event that fires when the request finishes; check ARequestResult.Success first, and read ARequestResult.ResultString for the raw response or error detail. Returned items are TTMSFNCCloudItem objects exposing FileName, Size, ID, ParentID, CreationDate and ModifiedDate.

Listing a folder

GetFolderList lists a folder — pass nil (or no argument) for the account root, or a folder item to list its contents. The items arrive in OnGetFolderList; FileLimit caps how many a single listing returns.

procedure TForm1.ListRootFolder;
begin
  TMSFNCCloudBox1.OnGetFolderList := BoxFolderListed;
  TMSFNCCloudBox1.FileLimit := 1000;   // cap items per listing (default 10000)
  TMSFNCCloudBox1.GetFolderList;        // pass nil / no argument for the root
end;

procedure TForm1.BoxFolderListed(Sender: TObject;
  const AFolderList: TTMSFNCCloudItems;
  const ARequestResult: TTMSFNCCloudBaseRequestResult);
var
  i: Integer;
begin
  if not ARequestResult.Success then
  begin
    ShowMessage('Box error: ' + ARequestResult.ResultString);
    Exit;
  end;

  ListBox1.Clear;
  for i := 0 to AFolderList.Count - 1 do
    ListBox1.Items.Add(AFolderList[i].FileName);
end;

For a recursive tree, GetFolderListHierarchical walks subfolders and reports completion through OnGetFolderListComplete. GetFileByID resolves a single item when you already hold its Box ID.

Reading item metadata

GetFileInfo (and GetFolderInfo) request metadata for one item by name or path; the result arrives in OnGetFileInfo as a TTMSFNCCloudBoxItem.

procedure TForm1.ShowFileInfo;
begin
  TMSFNCCloudBox1.OnGetFileInfo := BoxFileInfo;
  TMSFNCCloudBox1.GetFileInfo('/Reports/Q4.pdf');
end;

procedure TForm1.BoxFileInfo(Sender: TObject; const AFile: TTMSFNCCloudBoxItem;
  const ARequestResult: TTMSFNCCloudBaseRequestResult);
begin
  if ARequestResult.Success then
    Memo1.Lines.Add(Format('%s — %d bytes, id %s',
      [AFile.FileName, AFile.Size, AFile.ID]));
end;

Combining a listing with a follow-up request

Because each step is event-driven, you chain operations by starting the next one from the previous completion event. This lists the root, then requests info for the first item once the listing arrives:

procedure TForm1.BrowseAndInspect;
begin
  TMSFNCCloudBox1.OnGetFolderList := ListThenInspect;
  TMSFNCCloudBox1.OnGetFileInfo := BoxFileInfo;
  TMSFNCCloudBox1.GetFolderList;   // root
end;

procedure TForm1.ListThenInspect(Sender: TObject;
  const AFolderList: TTMSFNCCloudItems;
  const ARequestResult: TTMSFNCCloudBaseRequestResult);
begin
  if not ARequestResult.Success then
    Exit;

  // Drill into the first returned item once the listing arrives.
  if AFolderList.Count > 0 then
    TMSFNCCloudBox1.GetFileInfo(AFolderList[0].FileName);
end;

procedure TForm1.BoxFileInfo(Sender: TObject; const AFile: TTMSFNCCloudBoxItem;
  const ARequestResult: TTMSFNCCloudBaseRequestResult);
begin
  if ARequestResult.Success then
    Memo1.Lines.Add(AFile.FileName + ' — ' + IntToStr(AFile.Size) + ' bytes');
end;

Common mistakes

  • Reading results outside the event. A method returns before the network call completes — use the On... event, not the method's return value, for the data.
  • Ignoring ARequestResult.Success. A failed request still fires the event; always check Success before using the payload.
  • TTMSFNCCloudBox — GetFolderList, GetFolderListHierarchical, GetFileInfo, GetFileByID, FileLimit, OnGetFolderList

See also