怎样把一张jpeg格式的图片,先转换成二进制,然后再存入数据库的二进制子段 picture 怎样把一张jpeg格式的图片,先转换成二进制,然后再存入数据库的二进制子段 picture 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 它本身就是blob二进制的,直接存就可以了 procedure TForm1.RzButton4Click(Sender: TObject);var st: TStringStream; ft: Tfilestream; i : integer;begin query1.SQL.Clear; query1.SQL.Add('insert into rtuwav (picture) values(:picture)'); ft:=Tfilestream.Create('g:/123.jpeg',fmOpenRead ); st := tstringstream.Create(''); st.CopyFrom(ft,ft.Size); query1.ParamByName('picture').AsBlob:=st.DataString; query1.ExecSQL; freeandnil(ft); freeandnil(st);end; 那又如何转换回去呢这样我取出来了,又如何转换回去呢,因为我要在image中显示 源码如下: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. 发送的短信在手机不会自动换行 这个存储过程怎么改进?急! 晕,所有对话框系统都默认为ok,是不是盗版的问题? 大富翁論壇這幾天為何不能登陸,出什麼問題了? 可以登錄,可權限設置不了.為什麼?分不多,先謝過各位! 请问:怎样将图片(Bmp,Jpeg...)保存入数据库的ole字段中 dsf 请问大家在开发DELPHI三层结构时,是用MIDAS,还是MTS? 各位大哥指点一下:我该不该把我的这个程序里的BDE全干掉换成DBISM? 如何使用Windows本身的API来进行窗口的移动和大小调整 delphi里面支持正则吗?如果想实现类似正则的功能用什么好? ActiveX控件问题
var
st: TStringStream;
ft: Tfilestream;
i : integer;
begin
query1.SQL.Clear;
query1.SQL.Add('insert into rtuwav (picture) values(:picture)');
ft:=Tfilestream.Create('g:/123.jpeg',fmOpenRead );
st := tstringstream.Create('');
st.CopyFrom(ft,ft.Size);
query1.ParamByName('picture').AsBlob:=st.DataString;
query1.ExecSQL;
freeandnil(ft);
freeandnil(st);
end;
这样我取出来了,又如何转换回去呢,因为我要在image中显示
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);
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.