FM WS_FILENAME_GET

  CALL FUNCTION 'WS_FILENAME_GET'
    EXPORTING
      def_path         = 'C:\'  
      mask             = ',Excel file,*.xls;*.xlsx;'  
      mode             = '0'
      title            = 'Choose input file'
    IMPORTING
      filename         = p_local
    EXCEPTIONS
      inv_winsys       = 1
      no_batch         = 2
      selection_cancel = 3
      selection_error  = 4
      OTHERS           = 5.