对于SQL中的image型字段,如何存入一个图片;
存入后如果想取出如何显示(并且显示在image控件中该如何操作),请大家给出代码.
谢谢大家!

解决方案 »

  1.   

    DELPHI存取JPEG文件到SQL Server数据库
                                          高红岩(ghyghost)
    近日笔者书写一个小型的学生管理系统时,需要用到ADO控件存取SQL Server数据库图片,查看资料发现基本都是针对BMP文件进行操作(巨增数据库大小),但发现了★eagletian★高手翻译的ADO英文技术文档,里面涉及到了数据库存取JPEG文件的关键技术,在win98+sql server桌面版中测试通过,运行良好,现于源码公开如下:
    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);
    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;
      到此用DELPHI存取JPEG文件到SQL Server数据库中的具体操作已经叙述完毕。
      

  2.   

    http://218.56.9.158/default.aspx
    下载基地->数据库图片存储;
    下载一下参考吧。
    用accsse做的,和sql server极为相似,
      

  3.   

    save
      TBlobField(Query1.FieldByName('myimage')).LoadfromFile(OpenDialog1.Filename);show
      Image1.Picture.Graphic.Assign(TBlobField(Query1.FieldByName('myimage')));
      如果上面不对试试下面的,忘了语法了(在网吧)
      Image1.Picture.TBlobField(Query1.FieldByName('myimage'))
      

  4.   

    procedure TBaseDocForm.Button2Click(Sender: TObject);
    var olestream: TMemoryStream;
    begin
    if OpenDialog1.Execute then
        begin
           olestream:=TMemoryStream.Create;
           olestream.LoadFromFile(OpenDialog1.FileName);
           DataModule2.CarBaseDocADOQuery.Edit ;
           (DataModule2.CarBaseDocADOQuery.FieldByName('照片') as TBlobField).LoadFromStream(olestream);
          // ADOQuery1.Post;
         // SeSkinMessage1.ShowMessage('添加成功!');
           olestream.Free ;
        end
    else
        SeSkinMessage1.ShowMessage('请重新添加!');
    end;
      

  5.   

    things(平) (枕流以洗耳,漱石以磨牙) 
    image
    show时出错.
      

  6.   

    ghyghost(╔☆→向菜文作者转形←☆╝) 方法好!!
      

  7.   

    ghyghost(╔☆→向菜文作者转形←☆╝) 
    tblobfield(adoquery1.Fields[1]).loadfromstream(picstream);图片格式必须是bmp,不能是JPG,JEPG?