如何才能把一张图片直接存放到一张表中并从里面读取出来?
我的在表里定义了一个字段的类型为IMAGE型的。
是SQL SERVER中的表。
比如我的表的名称是SIMAGE
字段是 IMAGEFILED 类型是IMAGE
图片为A.JPG
我要怎么才能把一张图片存进去呢?
然后怎么才能读出来后并显示出来呢?
请给段代码谢谢...

解决方案 »

  1.   

    这是一个完整的例子(转贴,忘记原著名字)
    用adoquery,读写数据库的图片
    unit Unit1;interfaceuses
      Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,jpeg,
      ExtDlgs, Db, DBTables, StdCtrls, ExtCtrls, ADODB;type
      TForm1 = class(TForm)
        Button1: TButton;
        OpenPictureDialog1: TOpenPictureDialog;
        Button2: TButton;
        Image1: TImage;
        ADOQuery1: TADOQuery;
        ADOQuery2: TADOQuery;
        Edit1: TEdit;
        procedure Button1Click(Sender: TObject);
        procedure Button2Click(Sender: TObject);
      private
        { Private declarations }
      public
        { Public declarations }
        filename:string;
        procedure SetPicture(pos:string;TempQuery:TADOQuery);     /////往数据库中插入图片
        procedure GetPicture(pos:string;TempQuery:TADOQuery);      ////得到图片
      end;var
      Form1: TForm1;implementation{$R *.DFM}{ TForm1 }procedure TForm1.GetPicture(pos:string;TempQuery: TADOQuery);
    var
      MS_JpegStream:TMemoryStream;
    begin
      try
        MS_JpegStream:=TMemoryStream.Create;
        with tempQuery do
          begin
            close;
            sql.clear;
            //修改这个语句
            sql.Add('select picture from table where no=:pos');
            Parameters.ParamByName('pos').value:=pos;
            Open;
          end;
        if tempquery.FieldByName('image').isnull then
          begin
            image1.Picture.Graphic:=nil;
          end
        else
          begin
             (tempQuery.FieldByName('image') as tblobfield).savetostream(MS_JpegStream);
             image1.Picture.Graphic:=nil;
             image1.Picture.Graphic:=TJpegImage.Create;
             MS_JpegStream.Position:=0;
             image1.Picture.Graphic.LoadFromStream(MS_JpegStream);
          end;  finally
        MS_JpegStream.Free;
      end;end;procedure TForm1.SetPicture(pos:string; TempQuery: TADOQuery);
    var
      MS_JpegStream:TMemoryStream;
      M_BitMap:TBitMap;
      M_Jpeg:TJpegImage;
    begin
      try
        MS_JpegStream:=TMemoryStream.Create;
        M_BitMap:=TBitMap.Create;
        M_Jpeg:=TJpegImage.Create;
        if extractfileext(filename)='.bmp' then
          begin
            M_BitMap.LoadFromFile(filename);
            M_Jpeg.Compress;
            M_Jpeg.Assign(M_BitMap);
          end
        else if extractfileext(filename)='.jpg' then
          begin
            M_Jpeg.LoadFromFile(filename);
          end;
        M_Jpeg.SaveToStream(MS_JpegStream);
        with tempQuery do
          begin
            close;
            sql.clear;
    //修改这个语句
            sql.Add('insert into table (no,IMage) values (:pos,:image)');
            Parameters.ParamByName('pos').Value:=pos;
            Parameters.ParamByName('image').LoadFromStream(MS_JpegStream,ftblob);        ExecSQL;
          end;
      finally
        MS_JpegStream.Free;
        M_BitMap.Free;
        M_Jpeg.Free;
      end;
    end;procedure TForm1.Button1Click(Sender: TObject);//打开图片并写入数据库
    begin
      if openpicturedialog1.Execute then
      begin
       filename:=openpicturedialog1.FileName;
       SetPicture(edit1.text,ADOQuery1);
      end
    end;procedure TForm1.Button2Click(Sender: TObject);//显示图片
    begin
      getpicture(edit1.text,ADOQuery2);
    end;end.