string mystring = "provider   =   microsoft.jet.oledb.4.0   ;   data   source   =   " + path + ";extended   properties=excel   8.0 ";
        OleDbConnection cnnxls = new OleDbConnection(mystring);
        OleDbDataAdapter myda = new OleDbDataAdapter("select   *   from   [Sheet1$] ", cnnxls);
        DataSet myds = new DataSet();
        myda.Fill(myds);//就是这句话出现了问题