THPDFDocumentHandlerStatus Type
THPDFDocumentHandlerStatus = (
dhsNotRun, dhsSucceeded, dhsNoHandler, dhsInvalidOptions,
dhsInvalidSource, dhsUnsupportedContent, dhsBudgetExceeded,
dhsCancelled, dhsHandlerFailed, dhsDestinationFailed
);区分识别、验证、预算、取消、handler 和目标端各类结果，对预期内的失败无需借助异常