How to validate excel data before uploading to database using C#

/// <summary>
        /// Fetch Sheet As DataTable
        /// </summary>
        /// <param name="SheetName">SheetName</param>
        /// <returns>A DataTable</returns>
        public static System.Data.DataTable FetchSheet(string ExcelFilePath, string SheetName)
        {
            try
            {
                string sConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + ExcelFilePath + ";" + "Extended Properties='Excel 8.0;HDR=YES;'";
                OleDbConnection objConn = new OleDbConnection(sConnectionString);
                objConn.Open();
                OleDbCommand objCmdSelect = new OleDbCommand("SELECT * FROM [" + SheetName + "$]", objConn);
                OleDbDataAdapter objAdapter = new OleDbDataAdapter();
                objAdapter.SelectCommand = objCmdSelect;
                System.Data.DataTable dtReturned = new System.Data.DataTable();
                objAdapter.Fill(dtReturned);
                objConn.Close();
                return dtReturned;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return null;
            }
        }