procedure RollbackPageObjectEditTransaction;
RollbackPageObjectEditTransaction 會還原 BeginPageObjectEditTransaction 擷取的快照,捨棄所有已記錄的編輯,並關閉交易
在 CommitPageObjectEditTransaction 失敗之後,或當呼叫端決定該編輯群組不應生效時使用
if not Pdf1.CommitPageObjectEditTransaction then
Pdf1.RollbackPageObjectEditTransaction;