(PHP 4 >= 4.3.0, PHP 5)
fdf_set_target_frame — Set target frame for form display
Sets the target frame to display a result PDF defined with fdf_save_file() in.
The FDF document handle, returned by fdf_create(), fdf_open() or fdf_open_string().
The frame name, as a string.
成功时返回 TRUE, 或者在失败时返回 FALSE.