请问DELPHI中怎么处理BLOB字段？

shaw_jansin 2003-10-16 09:53:54

我想用QUERY控件insert tb1(blob) values(:para1),然后设置参数的方式添加带BLOB字段的记录，不知怎么处理比较合适，同时取出又该如何？
不想用TABLE控件（总是预取数据）！

...全文

280 5 打赏收藏转发到动态举报

写回复

用AI写文章

5 条回复

切换为时间正序

请发表友善的回复…

发表回复

shaw_jansin 2003-10-20

打赏
举报

soaringsouth 2003-10-16

打赏
举报

把数据库blob字段存到文件:
procedure TMainFrm.N4Click(Sender: TObject);
var
MStream:TStream;
MFileStream:TFileStream;
pImage: pointer;
FileName:string;
aFileName:String;
begin

SaveDialog1.FileName:=suiDBGrid2.DataSource.DataSet.FieldByName('filename').AsString;
SaveDialog1.Execute;
if not SaveDialog1.Execute then Exit ;
try
//从数据库读出文件信息
MStream:=suiDBGrid2.DataSource.DataSet.CreateBlobStream(suiDBGrid2.DataSource.DataSet.FieldbyName('Files'),bmRead);
FileName :=suiDBGrid2.DataSource.DataSet.FieldByName('FileName').asString ;
//组合文件名
aFileName := SaveDialog1.FileName;
MStream.Position:=0;
GetMem(pImage, MStream.Size);
//创建文件
MFileStream := TFileStream.Create(aFileName, fmCreate);
MStream.Read(pImage^,MStream.Size);
MFileStream.Write(pImage^ ,MStream.Size);
FreeMem(pImage);

MFileStream.Free ;
MStream.Free ;
except
if(MStream<>nil)then MStream:=nil ;
if(MFileStream<>nil)then MFileStream:=nil ;
exit;
end;
ShowMessage(SaveSuccess);
end;
再用ShellExecute打开

soaringsouth 2003-10-16

打赏
举报

//装载文件到流
MStream:=TMemoryStream.Create;
try
MStream.LoadFromFile(trim(edtfile.Text));
except
ShowMessage(OpenFileErr);
MStream.Free;
exit;
end;
.....

TBlobField(ADOTable1.FieldByName('files')).LoadFromStream(MStream);
try
ADOTable1.Post;

shaw_jansin 2003-10-16