(PHP 4 >= 4.3.0, PHP 5)
fdf_get_ap — Get the appearance of a field
Gets the appearance of a field (i.e. the value of the /AP key) and stores it in a file.
The FDF document handle, returned by fdf_create(), fdf_open() or fdf_open_string().
The possible values are FDFNormalAP, FDFRolloverAP and FDFDownAP.
The appearance will be stored in this parameter.
成功时返回 TRUE, 或者在失败时返回 FALSE.