Uplaod file within SAP BSP application using HTML and ABAP coding

<%@page language="abap" %>
<%@extension name="htmlb" prefix="htmlb" %>
<form method="POST" enctype="multipart/form-data">
   Please enter your file name by using the browse button:
   <br><input size="40" type="file" name="filename">
   <br><input type=submit name="onInputProcessing(upload)" value="Upload">
</form>

* event handler for checking and processing user input and
* for defining navigation
* data declarations
data: ld_value           type string,
      ld_entity          type ref to if_http_entity,
      ld_data            type xstring,
      ld_datatmp         type xstring,
      ld_filename        type string,
      ld_type            type string,
      ld_length          type string,
      ld_lengthtmp       type string,
      ld_numparts        type i,
      wa_binary_content  type SDOKCNTBIN,
      it_binary_content  type O2_DATA_TABLE.
data: ld_datastring      type string.
data: it_stringtab       type standard table of string.
data: ld_contsize        type i.
types: begin of t_char,
   text(1022) type c,
  end of t_char.
data: it_chartab         type STANDARD TABLE OF t_char.
*Constants for file processing
constants: con_tab  type c value cl_abap_char_utilities=>HORIZONTAL_TAB,
           new_line type c value cl_abap_char_utilities=>NEWLINE,
           cf type c value cl_abap_char_utilities=>CR_LF.
*User action value
case event_id.
  when 'upload'.
* find number of multiparts of file
    ld_numparts  = request->num_multiparts( ).
    do ld_numparts  times.
      ld_entity = request->get_multipart( sy-index ).
      ld_value  = ld_entity->get_header_field( '~content_filename' ).
      if not ld_value is initial.
        ld_filename = ld_value.
        ld_type = ld_entity->get_header_field( 'Content-Type' ).
*       Get file content
        ld_data = ld_entity->get_data( ).
*       Get size of file
        ld_length = xstrlen( ld_data ).
*       Move BINARY data into itab 1022 characters at a time
        ld_datatmp = ld_data.
        ld_lengthtmp = ld_length.
        while ld_lengthtmp > 1022.
          wa_binary_content-line = ld_datatmp(1022).
          append wa_binary_content to it_binary_content.
          shift ld_datatmp by 1022 places in byte mode.
          ld_lengthtmp = xstrlen( ld_datatmp ).
        endwhile.
*       Move remainder of file into table
        wa_binary_content-line = ld_datatmp.
        append wa_binary_content to it_binary_content.
*       Convert binary data table into char table, retains line breaks and
*       put each line of file into new table row
        ld_contsize = ld_lengthtmp.
        CALL FUNCTION 'SCMS_BINARY_TO_TEXT'
          EXPORTING
            INPUT_LENGTH          = ld_contsize
*            FIRST_LINE            = 0
*            LAST_LINE             = 0
            APPEND_TO_TABLE       = 'X'
*            MIMETYPE              = ' '
*            WRAP_LINES            = ' '
*            ENCODING              =
*         IMPORTING
*           OUTPUT_LENGTH         =
          TABLES
            BINARY_TAB            = it_binary_content
            TEXT_TAB              = it_chartab
          EXCEPTIONS
            FAILED                = 1
            OTHERS                = 2.
*       Convert binary data table into string field
        CALL FUNCTION 'SCMS_BINARY_TO_STRING'
          EXPORTING
            INPUT_LENGTH  = ld_contsize
*           FIRST_LINE    = 0
*           LAST_LINE     = 0
*           MIMETYPE      = ' '
*           ENCODING      =
          IMPORTING
            TEXT_BUFFER   = ld_datastring
*           OUTPUT_LENGTH =
          TABLES
            BINARY_TAB    = it_binary_content
          EXCEPTIONS
            FAILED        = 1
            OTHERS        = 2.
*       Split string value at line breaks into rows of itab
        split ld_datastring AT new_line INTO TABLE it_stringtab.
      endif.
    enddo.
endcase.