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






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();
            }
        }
    }








32.36.DataTable
32.36.1.Loop through DataTable by DataRow
32.36.2.Use DataTable to insert a Row
32.36.3.Add Row to DataTable
32.36.4.Accessing Data Values in a DataTable or DataSet
32.36.5.Adding Columns to DataTable
32.36.6.Adding Constraint to DataTable
32.36.7.Adding a Calculated Column to a DataTable
32.36.8.Adding a Column to a Child DataTable That Displays Data from the Parent Table
32.36.9.Adding a Column to a Parent DataTable That Aggregates a Child Table's Column Values
32.36.10.Creating a DataColumn and Adding It to a DataTable
32.36.11.Creating a DataTable and Adding It to a DataSet
32.36.12.Retrieving a Result Set Using a DataTable or a DataSet
32.36.13.Pop DataTable
32.36.14.Output Constraint Properties
32.36.15.Output the rows from the DataTable with foreach loop over DataRowCollection
32.36.16.Modify DataTable
32.36.17.Loop through the rows in DataTable
32.36.18.Creating Single- and Multi-Column Primary Keys
32.36.19.Creating a Unique Constraint
32.36.20.Append columns to DataTable
32.36.21.Accessing FirstName value in row 3 directly
32.36.22.Filter Sort
32.36.23.Retrieves a schema table for a query