Paradox 数据库中能否存储Jpeg格式的图片?请指点!

Question

BLOBFIELD.loadfromfile('jpgfile')
再用TJPEG类读取TBLOBSTREAM
...显示即可
或直接用JPEGIMG控件中的DBJPEGIMG。

Answer 1

procedure TForm1.Button2Click(Sender: TObject);
var
  MemSize: Integer;
  Buffer: PChar;
  MyFile: TFileStream;
  Stream: TBlobStream;
  filename:string;
begin
  OpenDialog1.Filter:='图形文件(*.jpg)|*.jpg';
  if OpenDialog1.Execute then
  begin
    filename:=OpenDialog1.FileName;
    MyFile:=TFileStream.Create(fileName,fmOpenRead);
    with table1 do
    begin
      Open;
      edit;
      Stream := TBlobStream.Create(FieldByName('PIC') as TBlobField, bmWrite);{‘Doc’为BLOB字段名}
      MemSize := MyFile.Size;
      Inc(MemSize);
      //增加的一字节给结尾的null
      Buffer := AllocMem(MemSize);
      try
        Stream.Seek(0, soFromBeginning);
       //流指针位置放到最前
        MyFile.Read(Buffer^,MemSize);
        Stream.Write(Buffer^,MemSize);
        FieldByName('Name').Asstring:=ExtractFileName(fileName);
        FieldByName('Size').Asstring:=inttostr(MemSize-1);
     finally
        MyFile.Free;
        Stream.Free;
     end;
       try
        table1.Post;
       except
         showmessage('保存失败！');
         halt;
       end;
     end;
   end;
end;

Answer 2

Procedure TForm1.Button1Click(Sender:TObject);
begin
Table1.Insert;
Table1Binary.LoadFromFile('C:\test.jpg');
Table1.post;
end;
Procedure TForm1.Button2Click(Sender:Tobject);
begin
Table1Binary.SaveToFile('c:\test1.jpg');
image1.Picture.LoadFromFile('c:\test1.jpg');
end;
**注：此处存放JPEG图片的字段为Binary类型的字段