在DELPHI中更简单的存取JPEG文件到SQLSERVER数据库

最近在CSDN上看到两篇关于《DELPHI中存取JPEG文件到SQLSERVER》中的文章之后,觉得其中讲述的方法虽然有可取之处,但颇费时,我这里有更简单的操作方法，而且安全可靠,不敢一人独享,愿发布出来与大家共享。在Delphi7.0+Win2000+SqlServer 2000中测试通过，运行良好，现将思路、源码公开如下：

解决思路：

1、 关键在于将打开的JPEG文件动态转换为Tbitmap对象并显示在Timage对象中；

2、 将显示的图片提交到数据库中。

本例中在SQLSERVER2000中建立了一个试例表：exam(xm char(10),photo image)；

程序源代码：

unit SavePic;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, ExtDlgs, ExtCtrls, DBCtrls, Grids, DBGrids, DB, ADODB, Buttons,

  StdCtrls,Jpeg;

type

  TForm1 = class(TForm)

    SpeedButton1: TSpeedButton;

    ADOConnection1: TADOConnection;

    Table1: TADOTable;

    DataSource1: TDataSource;

    DBGrid1: TDBGrid;

    DBImage1: TDBImage;

    Image1: TImage;

    SpeedButton2: TSpeedButton;

    OpenPictureDialog1: TOpenPictureDialog;

    Label1: TLabel;

    Label2: TLabel;

    Edit1: TEdit;

    SpeedButton3: TSpeedButton;

    procedure SpeedButton2Click(Sender: TObject);

    procedure SpeedButton1Click(Sender: TObject);

    procedure SpeedButton3Click(Sender: TObject);

  private

    { Private declarations }

  public

    { Public declarations }

  end;

var

  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.SpeedButton2Click(Sender: TObject);

var

  bmp1:TBitmap;

  jpg1:TJpegImage;

begin

  OpenPictureDialog1.DefaultExt:=GraphicExtension(TJpegimage);

  if OpenPictureDialog1.Execute then

     begin

     bmp1:=TBitmap.Create;

     jpg1:=TJpegImage.Create;

     try

     jpg1.LoadFromFile(OpenPictureDialog1.FileName);

     bmp1.Assign(jpg1);

     Image1.Picture.Bitmap.Assign(bmp1);

     finally

       jpg1.Free;

       bmp1.Free;

     end;

    end;

end;

procedure TForm1.SpeedButton1Click(Sender: TObject);

begin

  table1.Open;

  table1.insert;

  table1.fieldbyname('xm').asstring:=Edit1.Text;

  table1.FieldByName('photo').Assign(Image1.Picture);

  table1.post;

  table1.Refresh;

end;

end.