cpdf_set_keywords
(PHP 3 >= 3.0.8, PHP 4, PHP 5 <= 5.0.4)
cpdf_set_keywords -- Sets the keywords field of the pdf documentDescription
bool cpdf_set_keywords ( int pdf_document, string keywords )The cpdf_set_keywords() function sets the keywords of a pdf document. 如果成功则返回 TRUE，失败则返回 FALSE。
See also cpdf_set_title(), cpdf_set_creator() and cpdf_set_subject().