引用ComObj這個單元

Type
  Conn: TADOConnection;
  qry: TADOQuery;
  .
  .
  .

var
  Excel: OLEVariant;
  ExcelVersion: string;
begin
   try
      Excel := CreateOLEObject('EXCEL.Application');
      ExcelVersion := Excel.version;
   finally
      Excel.Quit;
      Excel := UnAssigned;
   end;
  Conn.Close;

  if ExcelVersion = '11.0' then
    //Excel2003及早期的版本
     Conn.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+
                            filename+';Extended Properties=excel 8.0;'+
                            'Persist Security Info=false;'  
  else //Excel2007及以後的版本
     Conn.ConnectionString:='Provider=Microsoft.ACE.OLEDB.12.0;Data Source='+
                            filename+';Extended Properties=excel 12.0;'+
                             'Persist Security Info=True';//注意不能為false


    Conn.LoginPrompt:=false;
    Conn.Connected:=true;
    qry.Connection:=Conn;
    qry.close;
    qry.SQL.Clear;
    qry.SQL.add('select * from ['+sheet1+'$]');
    qry.Active:=true;
    ...
end;
 

附上各個EXCEL版本的版本號：

版本號  Excel名稱

2.0       Excel 2.0

3.0       Excel 3.0

4.0       Excel 4.0

5.0       Excel 5.0

7.0       Excel 95

8.0       Excel 97

9.0       Excel 2000

10.0     Excel XP

11.0     Excel 2003

12.0     Excel 2007

13.0     Excel 2010