请问怎样在Sql数据库中用Delphi存取图片？

Question

存取JPEG文件
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.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;　

Answer 1

楼主应该先看一下这个,(100分啊,好可惜^^_^^):
http://community.csdn.net/Expert/topic/3277/3277402.xml?temp=.1504633

Answer 2

http://www.yesky.com/SoftChannel/72342371928440832/20030929/1733136_1.shtml对你有帮助

Answer 3

我是存储的声音，和图片一样，给你个例子
//新增告警声音（相当于存储图片）
procedure TFrm_Alarm.B_SOKClick(Sender: TObject);
var
  ADOQ_SoundA:TADOQuery;
  s:TStream;
begin
  try
    s:=TFileStream.Create(cxButtonEdit1.Text,fmopenread);
  except
    s.Free;
    Application.MessageBox('声音文件不正确，请检查路径是否正确','成都超讯提醒您',mb_ok+MB_ICONWARNING);
    exit;
  end;  ADOQ_SoundA:=TADOQuery.Create(nil);
  ADOQ_SoundA.Connection:=DM_DATABASELINK.ADO_CDLINK;
  try
    Screen.Cursor:=crHourGlass;
    with ADOQ_SoundA do
    begin
      close;
      sql.Clear;
      sql.Add('insert into FM_ALAMR_SOUND (SOUND_FILE,SOUND_MEMO) VALUES (:sfi,:sme) ');      parameters.ParamByName('sfi').LoadFromStream(s,ftblob);       //强制转化为二进制流文件(路径)
      Parameters.ParamByName('sme').Value:=Trim(cxTextEdit1.Text);      try
        ExecSQL;
        WriteOperateLog(UserMessage.UserID,UserMessage.UserName,'增加','增加声音文件 '+cxTextEdit1.Text);
      except
        Application.MessageBox('新增出错，请检查新增内容是否正确！','成都超讯提醒您',MB_OK+MB_ICONWARNING);
        WriteOperateLog(UserMessage.UserID,UserMessage.UserName,'错误','增加声音文件 '+cxTextEdit1.Text+ '出错误');
        exit;
      end;
    end;
    CreateAlarmSound;                                  //创建告警声音    cxButtonEdit1.Text:='';
    cxTextEdit1.Text:='';
  finally
    s.Free;
    ADOQ_SoundA.Free;
    Screen.Cursor:=crDefault;
  end;
end;//试听告警声音（相当于读取图片）
procedure TFrm_Alarm.cxLV_SoundDblClick(Sender: TObject);
var
  ADOQSound:TADOQuery;
begin
  if cxLV_Sound.Selected=nil then exit;  ADOQSound:=TADOQuery.Create(nil);
  ADOQSound.Connection:=DM_DATABASELINK.ADO_CDLINK;
  try
    with ADOQSound do
    begin
      close;
      sql.Clear;
      sql.Add('select Sound_File from FM_ALAMR_SOUND');
      sql.Add(' where SOUND_ID=:SID');      Parameters.ParamByName('SID').Value:= StrToInt(Trim(cxLV_Sound.Selected.Caption));      open;
      if not eof then
      begin
        TBlobField(FieldByName('Sound_File')).SavetoFile('C:\TempSound01.wav');   //保存流文件        sndplaysound(pchar('C:\TempSound01.wav'),snd_async);       //播放
        DeleteFile('C:\TempSound01.wav');                          //删除文件
      end
      else
      begin
        Application.MessageBox('该记录没有声音文件','成都超讯提醒您',MB_OK+MB_ICONWARNING);
      end;
    end;
  finally
    ADOQSound.Free;
  end;
end;

Answer 4

郁闷，这个问题怎么在这里给了100分，我开始才回答了一个不过只有20分，好可惜哟unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, DB, ADODB;type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Image1: TImage;
    OpenDialog1: TOpenDialog;
    ADOConnection1: TADOConnection;
    Button3: TButton;
    ADOQuery1: TADOQuery;
    Button4: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure Button4Click(Sender: TObject);
  private
    FS: TFileStream;
    MS: TMemoryStream ;
    SM: TStream;
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
var
  chFilePath : string;
begin
  OpenDialog1.Filter := '图片|*.BMP';
  if OpenDialog1.Execute then
      chFilePath := OpenDialog1.FileName ;
  FS := TFileStream.Create(chFilePath,fmOpenRead);
  Image1.Picture.Bitmap.LoadFromStream(FS);
  FS.Free;
end;procedure TForm1.Button2Click(Sender: TObject);
//图片存放
begin
  MS := TMemoryStream.Create ;
  Image1.Picture.Bitmap.SaveToStream(MS);
  Ms.Position := 0;
  AdoQuery1.Append;
  TBlobField(AdoQuery1.FieldByName('Pic')).LoadFromStream(MS);
  AdoQuery1.Post;
  Ms.Free;
  ShowMessage('Success');end;procedure TForm1.Button3Click(Sender: TObject);
//图片读取
begin
  try
    try
      SM := AdoQuery1.CreateBlobStream(AdoQuery1.FieldByName('Pic'),bmRead );
      if SM.Size > 0 then
        ShowMessage('有位图')
      else
        ShowMessage('无位图');
      Image1.Picture.Bitmap.LoadFromStream(SM);
    except
      raise Exception.Create('位图存放错误！');
    end;
  finally
    SM.Free;
  end;
end;procedure TForm1.FormCreate(Sender: TObject);
begin
  ADoConnection1.Connected  := True;
  AdoQuery1.SQL.Text := 'Select * From Pic';
  AdoQuery1.Open;
end;procedure TForm1.Button4Click(Sender: TObject);
//图片清除
begin
  AdoQuery1.Edit;
  TBlobField(AdoQuery1.FieldByName('Pic')).Clear;
  AdoQuery1.Post;
  ShowMessage('清除成功');
end;end.

Answer 5

把jpg或bmp保存为jpg：
imInput为TImage类型  if Assigned(imInput.Picture.Graphic) then begin
    if SameText(ExtractFileExt(sFileName),'.jpg') then begin
      jpg := TJpegImage.Create;
      ms := TMemoryStream.Create;
      try
        jpg.LoadFromFile(sfileName);
        bmp.LoadFromClipboardFormat(cf_BitMap,ClipBoard.GetAsHandle(cf_Bitmap),0);
        jpg.SaveToStream(ms);
        (adoDataSet.FieldByName('PICTURE') as TBlobField).LoadFromStream(ms);
      finally
        ms.Free;
        jpg.Free;
      end;{try}
    end{if}
    else if ExtractFileExt(sFileName) = '.bmp' then begin
      jpg := TJpegImage.Create;
      bmp := TBitMap.Create;
      ms := TMemoryStream.Create;
      bmp.LoadFromClipboardFormat(cf_BitMap,ClipBoard.GetAsHandle(cf_BitMap),0);
      try
        jpg.Assign(bmp);
        jpg.SaveToStream(ms);
        (adoDataSet.FieldByName('PICTURE') as TBlobField).LoadFromStream(ms);
      finally
        ms.Free;
        bmp.Free;
        jpg.Free;
      end;{try}
    end;
  end;{if}
读取jpg：        m_blob := adoDataSet.CreateBlobStream(adoDataSet.FieldByName('Picture'),bmRead);
        m_jpeg:=TJpegImage.Create;
        try
          if m_blob.Size<>0 then begin
            try
              m_jpeg.LoadFromStream(m_blob);
              imInput.Picture.Assign(m_jpeg);
              ImInput.Refresh;
            except
            end;{try}
          end
          else
            imInput.Picture.Assign(nil);
        finally
          m_jpeg.Free;
          m_blob.Free;
        end;{try}
      end;{if}
    finally
      adoDataSet.Free;
    end;{try}从一个工程中copy的，给点分吧！