OleDbConnection myOleDbConnection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source="+Server.MapPath(filepath)+";Extended Properties='Excel 8.0;IMEX=1'");
OleDbDataAdapter myOledbDataAdapter = new OleDbDataAdapter("SELECT * FROM [student$]",myOleDbConnection);
DataSet ds = new DataSet();
myOledbDataAdapter.Fill(ds);