No you can't, It has to be deal with outside of the SMARTFORMS.
There are several steps.
Before everything, your needs the following variables:
DATA:ls_control_param TYPE ssfctrlop.
DATA:ls_composer_param TYPE ssfcompop.
DATA:ls_job_output_info TYPE ssfcrescl.
DATA:lt_job_output_info TYPE TABLE OF ssfcrescl WITH HEADER LINE.
DATA: lt_pdf TYPE STANDARD TABLE OF tline.
DATA: lt_docs TYPE STANDARD TABLE OF docs.
DATA: l_file_size TYPE i.
1) SSF_FUNCTION_MODULE_NAME
To get the smartforms' function model
CALL FUNCTION 'SSF_FUNCTION_MODULE_NAME'
EXPORTING
formname = p_frm
IMPORTING
fm_name = fm_name
EXCEPTIONS
no_form = 1
no_function_module = 2
OTHERS = 3.
OPTIONAL STEP:
open the connection for pool
control_parameters-no_dialog = 'X'.
control_parameters-preview = 'X'.
control_parameters-getotf = 'X'.
control_parameters-no_open = 'X'.
control_parameters-no_close = 'X'.
CALL FUNCTION 'SSF_OPEN'
EXPORTING
control_parameters = control_parameters
" mail_appl_obj = appl_object_id
" mail_recipient = recipient_id
" mail_sender = sender_id
EXCEPTIONS
formatting_error = 1
internal_error = 2
send_error = 3
user_canceled = 4
OTHERS = 5.
2) call the function model via the first step.
CALL FUNCTION fm_name
EXPORTING
control_parameters = control_parameters
* output_options = ls_composer_param
* user_settings = ''
otry = ''
IMPORTING
* DOCUMENT_OUTPUT_INFO =
job_output_info = ls_job_output_info
TABLES
gt_likp = gt_likp[]
gt_lips = gt_lips[]
EXCEPTIONS
formatting_error = 1
internal_error = 2
send_error = 3
user_canceled = 4.
OPTIONAL STEP:
CALL FUNCTION 'SSF_CLOSE'
IMPORTING
job_output_info = ls_job_output_info
EXCEPTIONS
formatting_error = 1
internal_error = 2
send_error = 3
OTHERS = 4.
3) Get filename
CALL METHOD cl_gui_frontend_services=>file_open_dialog
EXPORTING
default_extension = 'PDF'
default_filename = '*.PDF'
file_filter = 'PDF Files (*.PDF)'
multiselection = ' '
CHANGING
file_table = l_it_filetable
rc = l_result.
4) Convert to pdf
CALL FUNCTION 'CONVERT_OTF_2_PDF'
EXPORTING
use_otf_mc_cmd = 'X'
IMPORTING
bin_filesize = l_file_size
TABLES
otf = ls_job_output_info-otfdata[]
doctab_archive = lt_docs[])
lines = lt_pdf[]
EXCEPTIONS
err_conv_not_possible = 1"PDF文件的具体内容（估计是二进制流）
err_otf_mc_noendmarker = 2
OTHERS = 3.
5) save file
CALL FUNCTION 'GUI_DOWNLOAD'
EXPORTING
bin_filesize = l_file_size
filename = filename
filetype = c_bin
TABLES
data_tab = lt_pdf.
