在程序中压缩sql server2000的数据库备份文件的代码
怎样压缩sql server2000的数据库备份文件,像rar一样?小弟有一7m的sql server2000
数据库备份文件,在程序中怎样压缩啊?
复制代码 代码如下:
procedure TForm1.Button2Click(Sender: TObject); var SHExecInfo: SHELLEXECUTEINFO; begin SHExecInfo.cbSize := sizeof(SHELLEXECUTEINFO); SHExecInfo.fMask := SEE_MASK_NOCLOSEPROCESS; SHExecInfo.Wnd := Handle; SHExecInfo.lpVerb := nil; SHExecInfo.lpFile := 'WinRAR.exe'; SHExecInfo.lpParameters := 'a e:\qwqw.rar e:\qwqw'; SHExecInfo.lpDirectory := nil; SHExecInfo.nShow := SW_SHOW; SHExecInfo.hInstApp := Handle; ShellExecuteEx(@SHExecInfo); WaitForSingleObject(SHExecInfo.hProcess, INFINITE); CloseHandle(SHExecInfo.hProcess); ShellExecute(application.MainForm.Handle,'open','winrar.exe',PChar('a e:\zqzq.rar e:\zqzq'),'',SW_show); ShowMessage('压缩完毕!'); }
这是一段压缩图片的代码,压缩文件原理相同,只需稍做改动即可。
复制代码 代码如下:
var mss: TMemoryStream; zip: TDeCompressionStream; zip1: TCompressionStream; fs : TFileStream; fBuf: Array[0..16383] of Byte; flen: Integer; //从数据库中取出图片 //...写出SQL语句以取得有图片的记录,此处从略 mss := TMemoryStream.Create; fs := TFileStream.Create('filename.jpg',fmCreate or fmOpenWrite); try TBlobField(Que.FieldByName('pic')).SaveToStream(mss); zip := TDeCompressionStream.Create(fs); try flen := zip.Read(fbuf, SizeOf(fBuf)); while flen > 0 do begin fs.Write(fbuf, flen); flen := zip.Read(fbuf, SizeOf(fBuf)); end; finally FreeAndNil(zip); end; finally mss.Free; fs.Free; end; //将文件filename.jpg中的图片保存到数据库 //...写出SQL语句,打开Que,并定位到要保存图片的记录,此处从略 fs := TFileStream.Create('filename.jpg',fmOpenRead); mss := TMemoryStream.Create; try zip1 := TCompressionStream.Create(clDefault,mss); try flen := fs.Read(fbuf, SizeOf(fBuf)); while flen > 0 do begin zip1.Write(fbuf, flen); flen := fs.Read(fbuf, SizeOf(fBuf)); end; //保存到数据库 TBlobField(Que.FieldByName('pic')).LoadFromStream(mss); Que.UpdateBatch(); //... finally zip1.Free; end; finally fs.Free; mss.Free; end;