MyConnection = new System.Data.OleDb.OleDbConnection("provider=Microsoft.Jet.OLEDB.4.0; Data Source=FILE EXCEL;Extended Properties=Excel 8.0;");
            MyCommand = new System.Data.OleDb.OleDbDataAdapter("SELECT * FROM [Foglio1$]", MyConnection);

            
            DtSet = new System.Data.DataSet();

            MyCommand.Fill(DtSet);

                      

            //connessione a DB
            SqlConnection conn = new SqlConnection("Data Source=NOMESERVER; Integrated Security=SSPI; Initial Catalog=NOMEDATABASE");

            String sql = "SELECT * FROM nometabellaDB";
            SqlDataAdapter adapter = new SqlDataAdapter(sql, conn);

                  
           adapter.Update(DtSet.Tables[0]);