delphi DBTreeview与数据库连接的数据存取

//操作：
procedure TForm1.act_GetListExecute(Sender: TObject);
begin
FieldList := TStringList.create;
TreeView1.items.BeginUpdate;
Table1.Close;   // 关键！这样才能在插入、更新、删除表数据后实现实时更新
Table1.Open;    // 关键！
Table1.first;
while not Table1.eof do
begin
TreeAddItem(TreeView1, GetFieldList, Table1.getBookmark, false);
Table1.next;
end;
FieldList.clear;

TreeView1.Alphasort;
TreeView1.items.Endupdate;
TreeView1.Refresh;
TreeView1.FullExpand;     // 全部展开
end;

//GetFieldList函数：
function TForm1.GetFieldList: TStringList;
begin
FieldList.clear;
FieldList.add(Table1.fieldbyname('Level1').AsString);
FieldList.add(Table1.fieldbyname('Level2').AsString);
FieldList.add(Table1.fieldbyname('Level3').Asstring);
Result := FieldList;
end;