再次开帖,一个关于数据库压缩的问题，一个菜鸟在郁闷中！！

Question

原函数如下：
function ACompactDB(Afilename:string):boolean;
var
   db:OleVariant;
   TempFile:string;
begin
   Result:=false;
    try
       TempFile:=ExtractFilePath(Afilename)+'TempName'+'.mdb';
       db.CompactDatabase(Afilename,TempFile);
       DeleteFile(Afilename);
       RenameFile(TempFile,Afilename);
       Result:=true;
     except
       on E:EOleException do
         DisplayMessage('压缩没有成功，请检查文件后重新压缩！');
     end;
为什么执行到db.CompactDatabase(Afilename,TempFile);时就报错：Invalid variant operation.请教是什么原因？

Answer 1

try
       TempFile:=ExtractFilePath(Afilename)+'TempName'+'.mdb';
       db:=createoleobject('JRO.JetEngine');
       db.CompactDatabase('Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+afilename+'','Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+tempfile+'');
       DeleteFile(Afilename);
       RenameFile(TempFile,Afilename);
     except
       on E:EOleException do
         showMessage('压缩没有成功，请检查文件后重新压缩！');
     end;

Answer 2

晕哦，还是不行，这次报：authentication failed

Answer 3

Const
  SConnectionString       = 'Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%s;'
                                +'Jet OLEDB:Database Password=%s;';
//=============================================================================
// Procedure: CompactDatabase
// Author   : ysai
// Date     : 2003-01-27
// Arguments: AFileName,APassWord:string
// Result   : boolean
//=============================================================================
function CompactDatabase(AFileName,APassWord:string):boolean;
//压缩与修复数据库,覆盖源文件
var
  STempFileName:string;
  vJE:OleVariant;
begin
  STempFileName:=GetTempPathFileName;
  try
    vJE:=CreateOleObject('JRO.JetEngine');
    vJE.CompactDatabase(format(SConnectionString,[AFileName,APassWord]),
        format(SConnectionString,[STempFileName,APassWord]));
    result:=CopyFile(PChar(STempFileName),PChar(AFileName),false);
    DeleteFile(STempFileName);
  except
    result:=false;
  end;
end;
function GetTempPathFileName():string;
//取得临时文件名
var
  SPath,SFile:array [0..254] of char;
begin
  GetTempPath(254,SPath);
  GetTempFileName(SPath,'~SM',0,SFile);
  result:=SFile;
  DeleteFile(result);
end;