Modify DataTable : DataTable « ADO.Net « C# / CSharp Tutorial

1. C# / CSharp Tutorial
2. ADO.Net
3. DataTable

using System;
using System.Data;
using System.Data.SqlClient;

    class ModifyDataTable
    {
        static void Main(string[] args)
        {
            string connString = @"server = .\sqlexpress;integrated security = true;database = northwind";
            string sql = @"select * from employees where country = 'UK'";
            SqlConnection conn = new SqlConnection(connString);
            try
            {
                SqlDataAdapter da = new SqlDataAdapter();
                da.SelectCommand = new SqlCommand(sql, conn);
                DataSet ds = new DataSet();
                da.Fill(ds, "employees");
                DataTable dt = ds.Tables["employees"];
                dt.Columns["firstname"].AllowDBNull = true;
                dt.Rows[0]["city"] = "Wilmington";
                DataRow newRow = dt.NewRow();
                newRow["firstname"] = "Roy";
                newRow["lastname"] = "Beatty";
                newRow["titleofcourtesy"] = "Sir";
                newRow["city"] = "Birmingham";
                newRow["country"] = "UK";
                dt.Rows.Add(newRow);
                foreach (DataRow row in dt.Rows)
                {
                    Console.WriteLine(row["firstname"]);
                    Console.WriteLine(row["lastname"]);
                    Console.WriteLine(row["city"]);
                }
            }
            catch (Exception e)
            {
                Console.WriteLine("Error: " + e);
            }
            finally
            {
                conn.Close();
            }
        }
    }