string str = "provider=microsoft.jet.oledb.4.0;data source=e:/test.xls;extended properties=/"excel 8.0;hdr=yes;imex=1;/" ";
        dataset ds=new dataset();
        private void form1_load(object sender, eventargs e)
        ...{
            oledbconnection con;
            oledbdataadapter myadapter;
            con = new oledbconnection(str);
            try
            ...{
                con.open();
                myadapter = new oledbdataadapter("select * from [sheet1$]", con);
                myadapter.fill(ds, "ds");
                datagridview1.datasource = ds.tables["ds"];
            }
            catch (exception ex)
            ...{
                throw new exception(ex.message);
            }
            finally ...{
                con.close();
            }