急问:如何用TDBImage控件显示图片? 我用SQL Server2000建的数据表,里面有个字段用来存储图片数据(是不是image类型?),现在我不知道怎么把一张图片存到我的数据表中去,而且怎么显示存储在数据表中的图片?应该是用TDBImage控件吧,具体怎么用,望赐教啊! 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 TDBImage 有属性的设置下就可以了。这个下面是不用TDBImage的方法,....function TDbBlobField.LoadFromFile(FileName: String): boolean;var MemSize :integer; Buffer :pchar; FileStream :TFileStream; BlobSteam :TBlobStream;begin try FileStream := TFileStream.Create(FileName,fmOpenRead); with FOwnerTable do begin BlobSteam := TBlobStream.Create(FBindField as TBlobField,bmWrite); MemSize := FileStream.Size ; inc(MemSize); Buffer := AllocMem(MemSize); try BlobSteam.Seek(0,soFromBeginning); FileStream.Read(Buffer^,MemSize); BlobSteam.Write(Buffer^,MemSize); finally BlobSteam.Free ; FileStream.Free ; end; end; Result := True; except Result := False; end;end;... 代码不全,仅参考。 设置DBImage的Datacource属性为DataSource1DataSource1的DataSet指定为Table1DBImage的DataField属性设置成你的那个字段名比如"TuPian"然后Table1.Append;//加载图片Table1.Post;打完收工 uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialog*, **tCtrls, 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; use jpeg就可以使用JPG图片了。 其实有一个很简单的方法存取图象(仅限BMP和JPEG)到数据库字段中,不需要使用流,我初学还不会流。 这是我的一个代码:unit Unitpic;interfaceuses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, DBCtrls, StdCtrls, DB, Grids, DBGrids, ADODB, Mask;type TForm1 = class(TForm) ADOTable1: TADOTable; DataSource1: TDataSource; DBGrid1: TDBGrid; ADOTable1DSDesigner: TWideStringField; ADOTable1DSDesigner2: TWideStringField; ADOTable1DSDesigner3: TBlobField; Button1: TButton; Button2: TButton; Button3: TButton; Button4: TButton; DBImage1: TDBImage; OpenDialog1: TOpenDialog; DBEdit1: TDBEdit; DBComboBox1: TDBComboBox; procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure Button4Click(Sender: TObject); procedure DBImage1Click(Sender: TObject); private { Private declarations } public { Public declarations } end;var Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);begin if not adotable1.Bof then adotable1.Prior;end;procedure TForm1.Button2Click(Sender: TObject);begin if not adotable1.Eof then adotable1.Next;end;procedure TForm1.Button3Click(Sender: TObject);begin adotable1.Insert;end;procedure TForm1.Button4Click(Sender: TObject);begin adotable1.Delete; if adotable1.Eof then showmessage('没有数据了!');end;procedure TForm1.DBImage1Click(Sender: TObject);begin if opendialog1.Execute then begin adotable1.Edit; ADOTable1DSDesigner3.LoadFromFile(opendialog1.FileName); end;end;end. 如果简单的用EDIT POST方式,将DBIMAGE属性连到某个字段,这样只能存bmp文件,如果用流方式连接文件,其他方式也可以存吧。。:) 还有一个问题:图片存在SQL Server2000数据表中,字段数值表现的是什么? 我的都还是<Binary> 如何通过类名和对象名获取对象实例 ★★哈哈哈哈!终于升星啦!散分散分★★ 有关考勤处理的问题? 制作动画片问题 请各位给个动态加载TreeView的例子。 如何实现 var1 := form1.Background; 请问:怎样实现将一放大镜放在图片上,点击image就放大一倍,点击两次再放大一倍??在线等待 什么控件可以像Excel那样下拉批量赋值 请问用QuickReport能自定义报表尺寸大小吗? Adoquery怎么赋值给Clientdataset 請教一個三層架構外網連接的原理問題? 如何取第3个'|'在字符串中出现的位置?有相关函数吗?
....
function TDbBlobField.LoadFromFile(FileName: String): boolean;
var MemSize :integer; Buffer :pchar;
FileStream :TFileStream;
BlobSteam :TBlobStream;
begin
try
FileStream := TFileStream.Create(FileName,fmOpenRead);
with FOwnerTable do
begin
BlobSteam := TBlobStream.Create(FBindField as TBlobField,bmWrite);
MemSize := FileStream.Size ;
inc(MemSize);
Buffer := AllocMem(MemSize);
try
BlobSteam.Seek(0,soFromBeginning);
FileStream.Read(Buffer^,MemSize);
BlobSteam.Write(Buffer^,MemSize);
finally
BlobSteam.Free ;
FileStream.Free ;
end;
end;
Result := True;
except
Result := False;
end;
end;...
代码不全,仅参考。
DataSource1的DataSet指定为Table1
DBImage的DataField属性设置成你的那个字段名比如"TuPian"
然后
Table1.Append;
//加载图片
Table1.Post;打完收工
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialog*,
**tCtrls, 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;
就可以使用JPG图片了。
其实有一个很简单的方法存取图象(仅限BMP和JPEG)到数据库字段中,不需要使用流,我初学还不会流。
这是我的一个代码:unit Unitpic;interfaceuses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, DBCtrls, StdCtrls, DB, Grids, DBGrids, ADODB, Mask;type
TForm1 = class(TForm)
ADOTable1: TADOTable;
DataSource1: TDataSource;
DBGrid1: TDBGrid;
ADOTable1DSDesigner: TWideStringField;
ADOTable1DSDesigner2: TWideStringField;
ADOTable1DSDesigner3: TBlobField;
Button1: TButton;
Button2: TButton;
Button3: TButton;
Button4: TButton;
DBImage1: TDBImage;
OpenDialog1: TOpenDialog;
DBEdit1: TDBEdit;
DBComboBox1: TDBComboBox;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure Button4Click(Sender: TObject);
procedure DBImage1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;var
Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
begin
if not adotable1.Bof then
adotable1.Prior;
end;procedure TForm1.Button2Click(Sender: TObject);
begin
if not adotable1.Eof then
adotable1.Next;
end;procedure TForm1.Button3Click(Sender: TObject);
begin
adotable1.Insert;
end;procedure TForm1.Button4Click(Sender: TObject);
begin
adotable1.Delete;
if adotable1.Eof then
showmessage('没有数据了!');
end;procedure TForm1.DBImage1Click(Sender: TObject);
begin
if opendialog1.Execute then
begin
adotable1.Edit;
ADOTable1DSDesigner3.LoadFromFile(opendialog1.FileName);
end;
end;end.