Delphi开发中ERP系统实现文件的上传下载查看删除功能

1、首先，需要数据控件做基本的配置

数据控件：

a.配置好数据控件的SQLupdate属性：

b.书写更新操作

UPDATE SRE_MSTR
SET
  SRE_NBR = :SRE_NBR, SRE_DATE = :SRE_DATE, SRE_VEND = :SRE_VEND, SRE_TYPE = :SRE_TYPE, SRE_RMKS = :SRE_RMKS, SRE_FILENAME = :SRE_FILENAME, 
  SRE_FILE_TYPE = :SRE_FILE_TYPE, SRE_REALNAME = :SRE_REALNAME, SRE_AUD_DESC = :SRE_AUD_DESC, SRE_PUR = :SRE_PUR, SRE_PUR_BY = :SRE_PUR_BY, 
  SRE_PUR_DATE = :SRE_PUR_DATE, SRE_QC = :SRE_QC, SRE_QC_BY = :SRE_QC_BY, SRE_QC_DATE = :SRE_QC_DATE, SRE_ENG = :SRE_ENG, SRE_ENG_BY = :SRE_ENG_BY, 
  SRE_ENG_DATE = :SRE_ENG_DATE, SRE_COM_ASS = :SRE_COM_ASS, SRE_PUR1 = :SRE_PUR1, SRE_PUR1_BY = :SRE_PUR1_BY, SRE_PUR1_DATE = :SRE_PUR1_DATE, SRE_QC1 = :SRE_QC1, 
  SRE_QC1_BY = :SRE_QC1_BY, SRE_QC1_DATE = :SRE_QC1_DATE, SRE_ENG1 = :SRE_ENG1, SRE_ENG1_BY = :SRE_ENG1_BY, SRE_ENG1_DATE = :SRE_ENG1_DATE, SRE_SUP_SCO = :SRE_SUP_SCO, 
  SRE_SUP_TYPE = :SRE_SUP_TYPE, SRE_CON = :SRE_CON, SRE_APRV = :SRE_APRV, SRE_APRV_BY = :SRE_APRV_BY, SRE_APRV_DATE = :SRE_APRV_DATE, SRE_VAL = :SRE_VAL, 
  SRE_INVAL = :SRE_INVAL, SRE_INVAL_BY = :SRE_INVAL_BY, SRE_INVAL_DATE = :SRE_INVAL_DATE, SRE_SITE = :SRE_SITE, SRE_WF_STATUS = :SRE_WF_STATUS, SRE_PROG_CODE = :SRE_PROG_CODE, 
  SRE_DOC_CODE = :SRE_DOC_CODE, SRE_CRT_BY = :SRE_CRT_BY, SRE_CRT_DATE = :SRE_CRT_DATE, SRE_MOD_TIMES = :SRE_MOD_TIMES, SRE_MOD_BY = :SRE_MOD_BY, SRE_MOD_DATE = :SRE_MOD_DATE, 
  SRE_PST = :SRE_PST, SRE_PST_BY = :SRE_PST_BY, SRE_PST_DATE = :SRE_PST_DATE, SRE_CHAR1 = :SRE_CHAR1, SRE_CHAR2 = :SRE_CHAR2, SRE_CHAR3 = :SRE_CHAR3, SRE_CHAR4 = :SRE_CHAR4, 
  SRE_CHAR5 = :SRE_CHAR5, SRE_CHAR6 = :SRE_CHAR6, SRE_QTY1 = :SRE_QTY1, SRE_QTY2 = :SRE_QTY2,
  SRE_FILE = EMPTY_BLOB(),SRE_FILE1 = EMPTY_BLOB(),SRE_FILENAME1=:SRE_FILENAME1
WHERE
  SRE_NBR = :Old_SRE_NBR
RETURNING
  SRE_FILE,SRE_FILE1
INTO 
  :SRE_FILE,:SRE_FILE1；

c.若采用流数据字段BLOB/CLOB来存储文件，则还应设置字段属性，如下：

至此，配置结束。

2、实现ERP系统中文件上传

procedure Tfrm_SLSUMT01.btn_UploadClick(Sender: TObject);
begin
  inherited;
  if sre_mstr.IsEmpty then exit;
  SaveRecord;
  sre_mstr.Edit;
 // sre_mstr.Cancel;

  UploadFileToDB(sre_mstr, 'sre_filename', 'sre_file');
end;

procedure Tfrm_SLSFMT01.UploadFileToDB(qry: TyyQuery; FieldName1,
  FieldName2: String);
var
  FileName: String;
begin
  //保存文件到数据库
  if (not qry.Active) then exit; 

  if qry = sfsd4_det then
  begin
    if not dlg_Open4.Execute then exit;
    FileName := dlg_Open4.FileName;
    try
      BeginWait;
      qry.Append;
      qry.F(FieldName1).AsString := ExtractFileName(FileName);
      TBlobField(qry.F(FieldName2)).LoadFromFile(FileName);
      qry.Post;
    finally
      StopWait;
    end;
  end;

 if qry = sfs_mstr then
  begin
    if not dlg_Open.Execute then exit;
    FileName := dlg_Open.FileName;
    try
      BeginWait;
      qry.Edit;
      qry.F(FieldName1).AsString := ExtractFileName(FileName);
      TBlobField(qry.F(FieldName2)).LoadFromFile(FileName);
      qry.Post;
    finally
      StopWait;
    end;
  end;
end;

3、实现ERP系统中文件下载

procedure Tfrm_SLSUMT01.btn_downloadClick(Sender: TObject);
var
   filename  :String;
begin
  inherited;
  if sre_mstr.F('sre_filename').AsString = '' then exit;
  if Ask(priMsg.GetMsg('041')) = ID_NO then exit;     //041=确定要下载当前文件吗?

  //文件名
  dlg_download.FileName := sre_mstr.F('sre_nbr').AsString + '_' +  sre_mstr.F('sre_filename').AsString ;

  if dlg_download.Execute then
  begin
    filename := dlg_download.FileName;
    TBlobField(sre_mstr.F('sre_file')).SaveToFile(FileName);
  with Query do
    begin
        try
          if not DTM.Conn.InTransaction then
            DTM.Conn.StartTransaction;
            ExecSQL;
          DTM.Conn.Commit;
        except
           if DTM.Conn.InTransaction then
             DTM.Conn.Rollback;
           Raise;
        end;
      end;
      ShowMsg(Format(priMsg.GetMsg('042'), [filename]));  //042=文件下载完成! (%s)
  end;
end;

4、实现ERP系统中文件查看

procedure Tfrm_SLSUMT01.btn_viewClick(Sender: TObject);
begin
  inherited;
  //查看文件
  if (sre_mstr.F('sre_filename').AsString = '') then exit;
  OpenFile(sre_mstr, 'sre_filename', 'sre_file')
end;
procedure Tfrm_SLSUMT01.OpenFile(qry: TyyQuery; FieldName1,
  FieldName2: String);
var
  FileName: String;
  path: array [0..MAX_PATH] of Char;
begin
  //查看文件
  if qry.Active and (not qry.IsEmpty) then
  begin
    GetTempPath(MAX_PATH, path);
    TEMP_FILE_PATH := path;
    if TEMP_FILE_PATH = '' then
      TEMP_FILE_PATH := '.';
    FileName := TEMP_FILE_PATH + '' + qry.F(FieldName1).AsString;
    TBlobField(qry.F(FieldName2)).SaveToFile(FileName);
    if FileExists(FileName) then
      ShellExecute(Application.Handle, PChar('Open'), PChar(FileName), nil, nil, SW_SHOW);
  end;
end;

5、实现ERP系统中文件删除功能

procedure Tfrm_SLSUMT01.btn_delClick(Sender: TObject);
begin
  inherited;
  //删除该项
  SaveRecord;
  if sre_mstr.Active and (not sre_mstr.IsEmpty) then
    if Ask(priMsg.GetMsg('040')) = ID_YES then  //040=确认要删除该文件吗?
      sre_mstr.Edit;
      sre_mstr.F('sre_filename').AsString := '';
      sre_mstr.F('sre_file').AsString := '';
      sre_mstr.Post;
  priMsg.ShowMsg('043'); //043=删除完成！
end;