写一个sap文件从服务器上传下载的

SAP系统中的文件上传和下载可以通过SAP内置的函数模块 `GUI_UPLOAD` 和 `GUI_DOWNLOAD` 来实现。下面是一个SAP文件上传下载的示例：

文件上传：

REPORT z_upload_file.

DATA: lv_file TYPE string VALUE 'C:\temp\test.txt',
      lt_data TYPE STANDARD TABLE OF soli WITH HEADER LINE.

* 读取本地文件数据
CALL FUNCTION 'GUI_UPLOAD'
  EXPORTING
    filename                    = lv_file
  TABLES
    data_tab                    = lt_data
  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
    header_not_allowed          = 8
    separator_not_allowed       = 9
    filesize_not_allowed        = 10
    header_too_long             = 11
    dp_error_create             = 12
    dp_error_send               = 13
    dp_error_write              = 14
    unknown_dp_error            = 15
    access_denied               = 16
    dp_out_of_memory            = 17
    disk_full                   = 18
    dp_timeout                  = 19
    file_not_found              = 20
    dataprovider_exception      = 21
    control_flush_error         = 22
    OTHERS                      = 23.

IF sy-subrc EQ 0.
  MESSAGE '文件上传成功' TYPE 'S'.
ELSE.
  MESSAGE '文件上传失败' TYPE 'E'.
ENDIF.

文件下载：

REPORT z_download_file.

DATA: lv_file TYPE string VALUE 'C:\temp\test.txt',
      lt_data TYPE STANDARD TABLE OF soli WITH HEADER LINE.

* 读取服务器文件数据
CALL FUNCTION 'GUI_DOWNLOAD'
  EXPORTING
    filename                    = lv_file
  TABLES
    data_tab                    = lt_data
  EXCEPTIONS
    file_write_error            = 1
    no_batch                    = 2
    gui_refuse_filetransfer      = 3
    invalid_type                = 4
    no_authority                = 5
    unknown_error               = 6
    header_not_allowed          = 7
    separator_not_allowed       = 8
    filesize_not_allowed        = 9
    header_too_long             = 10
    dp_error_create             = 11
    dp_error_send               = 12
    dp_error_write              = 13
    unknown_dp_error            = 14
    access_denied               = 15
    dp_out_of_memory            = 16
    disk_full                   = 17
    dp_timeout                  = 18
    file_not_found              = 19
    dataprovider_exception      = 20
    control_flush_error         = 21
    OTHERS                      = 22.

IF sy-subrc EQ 0.
  MESSAGE '文件下载成功' TYPE 'S'.
ELSE.
  MESSAGE '文件下载失败' TYPE 'E'.
ENDIF.

请根据实际需要，修改文件路径和文件名等参数。同时，需要注意的是，这种方式只适用于小文件的上传和下载。对于大文件，需要采用其他的方式，例如使用SAP数据传输工具（SAP Data Transfer Workbench）或者FTP等方式。