if(!IsPostBack)
{
string strCon="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" Server.MapPath("../xls_bang/bang.xls") ";Extended Properties='Excel 8.0;HDR=YES;IMEX=1'";
OleDbConnection oleCon=new OleDbConnection(strCon);
OleDbDataAdapter oleDA=new OleDbDataAdapter("select * from [Sheet1$]",oleCon);
DataSet ds=new DataSet();
oleDA.Fill(ds);
dgBang.DataSource=ds;
dgBang.DataBind();
}