Error when using the method cl_gui_frontend_services= file_open_dialog

Question

Hello Experts,
I am currently practicing BDC and I think the first step is to locate where my text file is. Now based on my code below, after selecting my text file nothing happens.
Also, what will be my next after getting the file from a specific location? Thanks guys!
REPORT  z_aris_practice_bdc_0
        NO STANDARD PAGE HEADING
        LINE-SIZE 255
        LINE-COUNT 64
        MESSAGE-ID zz.
*BDC Data
DATA: BEGIN OF bdc_tab OCCURS 0.
        INCLUDE STRUCTURE bdcdata.
DATA: END OF bdc_tab.
*Internal Table
DATA: BEGIN OF it_input OCCURS 0,
         user     TYPE usr02-bname,
         title    TYPE sza5_d0700-title_medi,
         lname    TYPE addr3_data-name_last,
         fname    TYPE addr3_data-name_first,
         initials TYPE addr3_data-initials,
         nickname TYPE addr3_data-nickname,
         function TYPE addr3_data-function,
      END OF it_input.
DATA: gt_lines TYPE sy-tabix,
      gt_file  TYPE filetable,
      wa_file  TYPE filetable,
      gt_subrc TYPE i.
*CONSTANTS
CONSTANTS: c_mask(60) TYPE c  VALUE ',..'.
*Selection Screen
SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE text-001.
PARAMETERS: p_input LIKE rlgrap-filename.
SELECTION-SCREEN END OF BLOCK b1.
AT SELECTION-SCREEN ON VALUE-REQUEST FOR p_input.
  CALL METHOD cl_gui_frontend_services=>file_open_dialog
    EXPORTING
   WINDOW_TITLE            =
   DEFAULT_EXTENSION       =
   DEFAULT_FILENAME        =
   FILE_FILTER             =
      initial_directory       = 'C:\Temp\'
      multiselection          = 'X'
    CHANGING
      file_table              = gt_file[]
      rc                      = gt_subrc
   USER_ACTION             =
    EXCEPTIONS
      file_open_dialog_failed = 1
      cntl_error              = 2
      error_no_gui            = 3
      OTHERS                  = 4.
  IF sy-subrc <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
           WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.
*START-OF-SELECTION
START-OF-SELECTION.
  PERFORM put_in_itab.
  PERFORM process_records.
*&      Form  get_files
      text
FORM put_in_itab.
  DATA: lv_file TYPE string.
  lv_file = p_input.
  CALL FUNCTION 'GUI_UPLOAD'
    EXPORTING
      filename                      = lv_file
    FILETYPE                      = 'ASC'
     has_field_separator           = 'X'
    HEADER_LENGTH                 = 0
    READ_BY_LINE                  = 'X'
    DAT_MODE                      = ' '
    CODEPAGE                      = ' '
    IGNORE_CERR                   = ABAP_TRUE
    REPLACEMENT                   = '#'
    CHECK_BOM                     = ' '
    VIRUS_SCAN_PROFILE            =
    NO_AUTH_CHECK                 = ' '
  IMPORTING
    FILELENGTH                    =
    HEADER                        =
    TABLES
      data_tab                      = it_input
   EXCEPTIONS
     file_open_error               = 1
     file_read_error               = 2
     no_batch                      = 3
     gui_refuse_filetransfer       = 4
     invalid_type                  = 5
     no_authority                  = 6
     unknown_error                 = 7
     bad_data_format               = 8
     header_not_allowed            = 9
     separator_not_allowed         = 10
     header_too_long               = 11
     unknown_dp_error              = 12
     access_denied                 = 13
     dp_out_of_memory              = 14
     disk_full                     = 15
     dp_timeout                    = 16
     OTHERS                        = 17
  IF sy-subrc <> 0.
    MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
            WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
  ELSE.
    DESCRIBE TABLE it_input LINES gt_lines.
  ENDIF.
ENDFORM.                    "get_files
*&      Form  process_records
      text
FORM process_records.
  LOOP AT it_input.
  ENDLOOP.
ENDFORM.                    "process_records

Answer 1

Hii viraylab,
go throgh this link..This sample code solves ur problem....
/people/milind.upasani/blog/2007/03/07/step-by-step-approach-to-ceate-simple-bdc-session-program-using-reusable-template
    U are new to BDC it seems...
    first u read the sap help ... then u will come know what to do after wards....
    http://help.sap.com/saphelp_47x200/helpdata/en/fa/097720543b11d1898e0000e8322d00/frameset.htm
Be familiar with the structure BDCDATA.
<b>Data transfers</b>  In this page..
Next u need to know about the <b>transaction RECORDER the tcode is SHDB.</b>
Nothing is difficult in this ..
For example When u r creating a data element in SE11 u go through some screens in a flow, by clicking some pushbuttons and by generating some function codes manually, and entering values manually...
But here u wont do it manually, these values will be populated from file into an internal table...
Before calling a transaction into which u r going to populate the data is to be filled into a table with structure <b>BDCDATA.</b>
<b>U need to use CALL TRANSACTION 'SE11' using BDCDATA or
the session method..</b>
Reward points for helpful answers...
sai ramesh