procedure Tform1.selectimageClick(Sender: TObject); //选择图像 begin if openpicturedialog1.Execute then image1.Picture.LoadFromFile(openpicturedialog1.FileName ); end; procedure Tform1.savetodbClick(Sender: TObject); //保存图像到数据库 var ext:string; begin if image1.picture.Graphic <> nil then //避免image1中无图像保存出错 begin adotable1.Edit ; adotable1.FieldByName(myimage).Assign(image1.Picture.Graphic); //以下记录保存到数据库的图像格式 ext:=extractfileext(openpicturedialog1.FileName ); //取出文件扩展名 if uppercase(ext) = .BMP THEN adotable1.FieldByName(isbmp).VALUE := 1 //BMP型图像数据 ELSE IF (UPPERCASE(EXT) = .JPEG) OR (UPPERCASE(EXT) = .JPG) THEN adotable1.FieldByName(isbmp).VALUE := 0; //JPEG型图像数据 ADOTABLE1.Post ; end; end;
2. 图像数据的读取及显示
procedure Tform1.ADOTable1AfterScroll(DataSet: TDataSet); //ADOTable1的AfterScroll事件方法程序 var jpegimage:tjpegimage; begin image1.Picture.Graphic :=nil; //下边BMP、JPEG两种图像数据必需分别处理 if adotable1.fieldbyname(isbmp).Asstring = 1 then //BMP型图像数据 image1.Picture.bitmap.Assign(adotable1.fieldbyname(myimage)) //上边语句中的bitmap不能为graphic,否则会出错 else if adotable1.fieldbyname(isbmp).asstring = 0 then //JPEG型图像数据 begin //begin2 jpegimage := tjpegimage.Create ; //通过jpegimage将图像显示在image1,否则会出错 try jpegimage.Assign(adotable1.fieldbyname(myimage)); image1.Picture.Graphic :=jpegimage; finally jpegimage.Free ; end; //end try end; //end begin2 end;
