实现FTP的文件上传与下载

在SAP的实际应用中，经常会需要将生成的文件上传到FTP，或从FTP下载相关文档数据。本例实现将本地指定文件上传到FTP，及从FTP下载文件到本地的功能。

从FTP复制文件共有两种方式，一种是直接复制文件，另一种方式是先从FTP读取文件数据到内表，拷贝再写入指定位置文件，不过该功能仅支持文本格式文件（*.TXT,*.DAT），一般不予推荐。

相关函数：

1）FTP_CONNECT：通过账号连接FTP。

2）FTP_COMMAND：执行FTP操作命令（注意，程序中所有命令必须为小写）。

1cd：指定本地文件夹路径；

cd：指定FTP文件夹路径；

put <filename>：上传文件；

get <filename>：下载文件；

3）FTP_SERVER_TO_R3：将FTP上的指定文本文件数据读取到内表。

4）FTP_DISCONNECT：关闭FTP连接。

REPORT ZR_EXAMPLE_07 .
DATA: KEY TYPE I VALUE 26101957,
TRFCDEST   LIKE RFCDES-RFCDEST,
THANDLE    TYPE I.

INCLUDE:<ICON>.
*定义输入界面
SELECTION-SCREEN:BEGIN OF BLOCK FTPLOGIN WITH FRAME TITLE TEXT-001.
PARAMETERS: P_USER(45) LOWER CASE OBLIGATORY MEMORY ID USR,
P_PWD(45) MODIF ID PWD LOWER CASE OBLIGATORY MEMORY ID PWD,
P_HOST(15) MEMORY ID HOS OBLIGATORY,
FTP_PATH(30) MEMORY ID FPOS OBLIGATORY.
SELECTION-SCREEN:END OF BLOCK FTPLOGIN.

SELECTION-SCREEN:BEGIN OF BLOCK UPLOAD WITH FRAME TITLE TEXT-002.
PARAMETERS: P_UPPATH(45),
P_FILE(20) .
SELECTION-SCREEN: BEGIN OF LINE.
SELECTION-SCREEN: PUSHBUTTON 1(20) PUBU USER-COMMAND UPLOAD.
SELECTION-SCREEN: END OF LINE.
SELECTION-SCREEN:END OF BLOCK UPLOAD.

SELECTION-SCREEN:BEGIN OF BLOCK DOWNLOAD WITH FRAME TITLE TEXT-003.
PARAMETERS: DL_PATH(45),
DL_FILE(20) .
SELECTION-SCREEN: BEGIN OF LINE.
SELECTION-SCREEN: PUSHBUTTON 1(20) GEBU USER-COMMAND DOWNLOAD.
SELECTION-SCREEN: PUSHBUTTON 24(30) SHBU USER-COMMAND ITAB_DL.
SELECTION-SCREEN: END OF LINE.
SELECTION-SCREEN:END OF BLOCK DOWNLOAD.

AT SELECTION-SCREEN OUTPUT.
* 对密码输入栏进行加密处理
PERFORM MASK_PWD.

* 给各按钮加入文本及图标
WRITE ICON_OUTGOING_OBJECT  AS ICON TO PUBU.
CONCATENATE PUBU 'Upload FTP' INTO PUBU SEPARATED BY SPACE.

WRITE ICON_INCOMING_OBJECT  AS ICON TO GEBU.
CONCATENATE GEBU 'FTP download' INTO GEBU SEPARATED BY SPACE.

WRITE ICON_WRITE_FILE  AS ICON TO SHBU.
CONCATENATE SHBU 'Internal table download' INTO SHBU SEPARATED BY
SPACE.

AT SELECTION-SCREEN.
PERFORM FTPCONNECT.
IF SY-SUBRC <> 0.
MESSAGE I001(00) WITH 'Can''t connect to FTP!'.
EXIT.
ENDIF.

MESSAGE S001(00) WITH 'FTP connect OK!'.
CASE SY-UCOMM.
WHEN 'ONLI'.
PERFORM FTPDISCONNECT.
EXIT.
ENDCASE.

*执行FTP功能
PERFORM FTP_EXECUTE.
*关闭FTP连接
PERFORM FTPDISCONNECT.
*-----------------------------------------------------------------------------*
*       改变密码输入框显示属性，实现密码保护        *
*-----------------------------------------------------------------------------*
FORM MASK_PWD.
LOOP AT SCREEN .
IF SCREEN-NAME = 'P_PWD'.
SCREEN-INVISIBLE = '1'.
MODIFY SCREEN .
CONTINUE.
ENDIF.
ENDLOOP.
ENDFORM.                    "

*-----------------------------------------------------------------------------*
*       通过IP、用户名、密码连接FTP服务器         *
*-----------------------------------------------------------------------------*
FORM FTPCONNECT.
DATA: THOSTS(45),TUSERS(45),TPWORD(45).
THOSTS = P_HOST.
TUSERS = P_USER.
TPWORD = P_PWD.
* 对密码数值进行加密解析处理
CALL 'AB_RFC_X_SCRAMBLE_STRING'     " System Function
ID 'SOURCE'      FIELD TPWORD
ID 'KEY'         FIELD KEY
ID 'SCR'         FIELD 'X'
ID 'DESTINATION' FIELD TPWORD
ID 'DSTLEN'      FIELD 64.

* 定义RFC连接目标，前后台执行时不同
IF SY-BATCH = 'X'.
TRFCDEST = 'SAPFTPA'.
ELSE.
TRFCDEST = 'SAPFTP'.
ENDIF.

*该函数可以定义有网关时账户密码，一般公司内部访问时无此设置
CALL FUNCTION 'FTP_CONNECT'
EXPORTING
USER                 = TUSERS
PASSWORD             = TPWORD
HOST                 = THOSTS
RFC_DESTINATION      = TRFCDEST
IMPORTING
HANDLE                = THANDLE
EXCEPTIONS
NOT_CONNECTED     = 1
OTHERS                = 2.
ENDFORM.                " FTPCONNECT
*&---------------------------------------------------------------------
*&     设置结束时关闭SAP
*&---------------------------------------------------------------------
FORM FTPDISCONNECT.
CALL FUNCTION 'FTP_DISCONNECT'
EXPORTING
HANDLE = THANDLE.
ENDFORM.                    " FTPDISCONNECT
*&---------------------------------------------------------------------*
*&      通过SAP执行命令上传或下载FTP文件
*&---------------------------------------------------------------------*
FORM FTP_EXECUTE.
DATA:TSUBRC LIKE SY-SUBRC.
DATA:BEGIN OF COM OCCURS 0,
CMD(100) TYPE C,
END OF COM.
DATA:BEGIN OF RES OCCURS 0,
LINE(100) TYPE C,
END OF RES.

*指定FTP文件夹路径
IF NOT FTP_PATH IS INITIAL.
CONCATENATE 'cd' FTP_PATH INTO COM-CMD SEPARATED BY ' '.
APPEND COM.
ENDIF.

CASE SY-UCOMM.
WHEN 'UPLOAD'.
*指定上传文件夹路径及上传文件命令
CONCATENATE 'lcd' P_UPPATH INTO COM-CMD SEPARATED BY ' '.
APPEND COM.
CONCATENATE 'put' P_FILE INTO COM-CMD SEPARATED BY ' '.
APPEND COM.

WHEN 'DOWNLOAD'.
*指定下载文件夹路径及下载文件命令
CONCATENATE 'lcd' DL_PATH INTO COM-CMD SEPARATED BY ' '.
APPEND COM.
CONCATENATE 'get' DL_FILE INTO COM-CMD SEPARATED BY ' '.
APPEND COM.
ENDCASE.

LOOP AT COM FROM 1.
IF COM-CMD <> ''.
*执行FTP指令
CALL FUNCTION 'FTP_COMMAND'
EXPORTING
HANDLE        = THANDLE
COMCOMMAND       = COM-CMD
TABLES
DATA          = RES
EXCEPTIONS
TCPIP_ERROR   = 1
COMMAND_ERROR = 2
DATA_ERROR    = 3
OTHERS        = 4.

*当执行失败时回执数据并退出
IF SY-SUBRC <> 0.
CASE SY-UCOMM.
WHEN 'UPLOAD'.
MESSAGE E001(00) WITH 'FTP UPLOAD FAIL!'.
WHEN 'DOWNLOAD'.
MESSAGE E001(00) WITH 'FTP DOWNLOAD FAIL!'.
ENDCASE.
EXIT.
ELSE.

*根据不同按钮的功能码判断程序执行逻辑及回执信息，当选择从内表下载功能时转入子程序
CASE SY-UCOMM.
WHEN 'UPLOAD'.
MESSAGE S001(00) WITH 'FTP UPLOAD SUCCESS!'.
WHEN 'DOWNLOAD'.
MESSAGE S001(00) WITH 'FTP DOWNLOAD SUCCESS!'.
WHEN 'ITAB_DL'.
PERFORM DL_ITAB USING THANDLE DL_PATH DL_FILE.
ENDCASE.
ENDIF.
ENDIF.
ENDLOOP.

CLEAR:COM,RES,TSUBRC.
REFRESH:COM,RES.
ENDFORM.                    " FTPPUTFILE

*---------------------------------------------------------------------*
*      将FTP文本类型文件数据读取到内表       *
*---------------------------------------------------------------------*
FORM DL_ITAB USING THANDLE  TYPE I
VALUE(FILEPATH) TYPE C
FILENAME TYPE C.
DATA: BEGIN OF BLOB OCCURS 0,
LINE(255) TYPE C,
END OF BLOB.
*连接字符串定义本地文件具体路径
CONCATENATE FILEPATH FILENAME INTO FILEPATH.

*将FTP文本类型文件数据读取到内表
*若所读FTP文件为非文本文件（*.txt,*.dat）时将出现错误
CALL FUNCTION 'FTP_SERVER_TO_R3'
EXPORTING
HANDLE = THANDLE
FNAME  = FILENAME
TABLES
BLOBBLOB   = BLOB.

*读取文件失败时退出程序并回执错误
IF SY-SUBRC <> 0.
MESSAGE E001(00) WITH 'Read FTP File FAIL!'.
EXIT.
ENDIF.

*将内表数据下载到本地文件
CALL FUNCTION 'WS_DOWNLOAD'
EXPORTING
FILENAME            = FILEPATH
FILETYPE            = 'DAT'
TABLES
DATA_TAB            = BLOB
EXCEPTIONS
FILE_OPEN_ERROR     = 1
FILE_WRITE_ERROR    = 2
INVALID_FILESIZE    = 3
INVALID_TABLE_WIDTH = 4
INVALID_TYPE        = 5.

*将数据写入本地文件失败时回执错误
IF SY-SUBRC <> 0.
MESSAGE E001(00) WITH 'FTP Download By Internal table FAIL!'.
ELSE.
MESSAGE S001(00) WITH 'FTP Download By Internal table SUCCESS!'.
ENDIF.
ENDFORM.