图片存入数据库的问题! 我用的数据库是SQLServer2000,想实现的是把图片存入数据库以及可以调用出来。具体应该怎么做呢?用什么控件来显示从数据库中取出来的图片呢?数据库中存的类型又是什么呢?各位看看能不能给个例子啊? 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 unit Unit1;interfaceuses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, ExtCtrls, DBCtrls, Grids, DBGrids, Db, ADODB,jpeg, StdCtrls,dbtables; {一定要USES JPEG单元,使能存储JPG文件格式}type TForm1 = class(TForm) DataSource1: TDataSource; ADOQuery1: TADOQuery; DBGrid1: TDBGrid; DBNavigator1: TDBNavigator; Image1: TImage; savebutton: TButton; showbutton: TButton; OpenDialog1: TOpenDialog; ADOQuery1id: TIntegerField; ADOQuery1pic: TBlobField; procedure savebuttonClick(Sender: TObject); procedure showbuttonClick(Sender: TObject); procedure DBNavigator1Click(Sender: TObject; Button: TNavigateBtn); private { Private declarations } public { Public declarations } end;var Form1: TForm1;implementation{$R *.DFM}function JpegStartsInBlob(PicField:TBlobField):integer; var ghy: TADOBlobstream; buffer:Word; hx: string; begin Result := -1; ghy := TADOBlobstream.Create(PicField, bmRead); try while (Result = -1) and (ghy.Position + 1 < ghy.Size) do begin ghy.ReadBuffer(buffer, 1); hx:=IntToHex(buffer, 2); if hx = ’FF’ then begin ghy.ReadBuffer(buffer, 1); hx:=IntToHex(buffer, 2); if hx = ’D8’ then Result := ghy.Position - 2 else if hx = ’FF’ then ghy.Position := ghy.Position-1; end; //if end; //while finally ghy.Free end; //try end;procedure TForm1.savebuttonClick(Sender: TObject);varpicstream:tadoblobstream;beginadoquery1.edit;picstream:=tadoblobstream.Create(tblobfield(adoquery1.fields[1]),bmWrite);if form1.opendialog1.execute thenbeginpicstream.LoadFromFile(opendialog1.filename);picstream.Position:=0;adoquery1.edit;tblobfield(adoquery1.Fields[1]).loadfromstream(picstream);adoquery1.post;end;end;procedure TForm1.showbuttonClick(Sender: TObject);varghy:TADOBlobstream;pic:tjpegimage;beginghy := TADOBlobstream.Create(Adoquery1pic, bmRead);try ghy.Seek(JpegStartsInBlob(Adoquery1pic),soFromBeginning); Pic:=TJpegImage.Create; try Pic.LoadFromStream(ghy); Image1.Picture.Graphic:=Pic; finally Pic.Free; end;finallyghy.Freeend;end;procedure TForm1.DBNavigator1Click(Sender: TObject; Button: TNavigateBtn);beginif button in [nbFirst, nbPrior, nbNext, nbLast] then showbutton.Click;end;end.如果数据库中要存储的是BMP文件,则在procedure TForm1.showbuttonClick(Sender: TObject);过程中代码更改如下即可存储显示BMP文件格式的操作。procedure TForm1.showbuttonClick(Sender: TObject);varghy:TADOBlobstream;pic:tbitmap;beginghy := TADOBlobstream.Create(Adoquery1pic, bmRead);try { ghy.Seek(JpegStartsInBlob(Adoquery1pic),soFromBeginning);} Pic:=Tbitmap.Create; try Pic.LoadFromStream(ghy); Image1.Picture.Graphic:=Pic; finally Pic.Free; end;finallyghy.Freeend;end; 到此用DELPHI存取JPEG文件到SQL Server数据库中的具体操作已经叙述完毕。 请教:delphi7 按F9运行报错. 请教老前辈,关于立体动画实现的算法,大分赠送。 关于fastreport的三个问题??? 如何得到delete后,所影响的记录数??? 为什么要学习数据结构? 关于Query的Datasource用法 熟悉TNMPOP3构件的,请进…… ADOQuery的问题 大侠们~~~~~可知Async Professional控件的安装码? 存储过程错误处理,(高手请进) 人事管理系统 如何保持文件打开状态?
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
ExtCtrls, DBCtrls, Grids, DBGrids, Db, ADODB,jpeg, StdCtrls,dbtables;
{一定要USES JPEG单元,使能存储JPG文件格式}
type
TForm1 = class(TForm)
DataSource1: TDataSource;
ADOQuery1: TADOQuery;
DBGrid1: TDBGrid;
DBNavigator1: TDBNavigator;
Image1: TImage;
savebutton: TButton;
showbutton: TButton;
OpenDialog1: TOpenDialog;
ADOQuery1id: TIntegerField;
ADOQuery1pic: TBlobField;
procedure savebuttonClick(Sender: TObject);
procedure showbuttonClick(Sender: TObject);
procedure DBNavigator1Click(Sender: TObject; Button: TNavigateBtn);
private
{ Private declarations }
public
{ Public declarations }
end;var
Form1: TForm1;implementation{$R *.DFM}function JpegStartsInBlob(PicField:TBlobField):integer;
var
ghy: TADOBlobstream;
buffer:Word;
hx: string;
begin
Result := -1;
ghy := TADOBlobstream.Create(PicField, bmRead);
try
while (Result = -1) and (ghy.Position + 1 < ghy.Size) do
begin
ghy.ReadBuffer(buffer, 1);
hx:=IntToHex(buffer, 2);
if hx = ’FF’ then begin
ghy.ReadBuffer(buffer, 1);
hx:=IntToHex(buffer, 2);
if hx = ’D8’ then Result := ghy.Position - 2
else if hx = ’FF’ then
ghy.Position := ghy.Position-1;
end; //if
end; //while
finally
ghy.Free
end; //try
end;
procedure TForm1.savebuttonClick(Sender: TObject);
var
picstream:tadoblobstream;
begin
adoquery1.edit;
picstream:=tadoblobstream.Create(tblobfield(adoquery1.fields[1]),bmWrite);
if form1.opendialog1.execute then
begin
picstream.LoadFromFile(opendialog1.filename);
picstream.Position:=0;
adoquery1.edit;
tblobfield(adoquery1.Fields[1]).loadfromstream(picstream);
adoquery1.post;
end;
end;procedure TForm1.showbuttonClick(Sender: TObject);
var
ghy:TADOBlobstream;
pic:tjpegimage;
begin
ghy := TADOBlobstream.Create(Adoquery1pic, bmRead);
try
ghy.Seek(JpegStartsInBlob(Adoquery1pic),soFromBeginning);
Pic:=TJpegImage.Create;
try
Pic.LoadFromStream(ghy);
Image1.Picture.Graphic:=Pic;
finally
Pic.Free;
end;
finally
ghy.Free
end;
end;procedure TForm1.DBNavigator1Click(Sender: TObject; Button: TNavigateBtn);
begin
if button in [nbFirst, nbPrior, nbNext, nbLast] then showbutton.Click;
end;end.如果数据库中要存储的是BMP文件,则在procedure TForm1.showbuttonClick(Sender: TObject);过程中代码更改如下即可存储显示BMP文件格式的操作。
procedure TForm1.showbuttonClick(Sender: TObject);
var
ghy:TADOBlobstream;
pic:tbitmap;
begin
ghy := TADOBlobstream.Create(Adoquery1pic, bmRead);
try
{ ghy.Seek(JpegStartsInBlob(Adoquery1pic),soFromBeginning);}
Pic:=Tbitmap.Create;
try
Pic.LoadFromStream(ghy);
Image1.Picture.Graphic:=Pic;
finally
Pic.Free;
end;
finally
ghy.Free
end;
end;
到此用DELPHI存取JPEG文件到SQL Server数据库中的具体操作已经叙述完毕。