C# - How to Export Data from SQL Server Table or View to Text File in C Sharp

Scenario: Download Script

You are working as C# developer. You are asked to write a program that should read the data from a table, view or function and write the results to flat file. Each time you run the program it should get the data from table or view and create flat file with date-time.

The below program will create flat file on each execution with results extracted from a table or view.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.Data.SqlClient;
using System.Data;


namespace TechBrothersIT.com_CSharp_Tutorial
{
    class Program
    {
        static void Main(string[] args)
        {

            string datetime = DateTime.Now.ToString("yyyyMMddHHmmss");
            string LogFolder = @"C:\Log\";
            try
            {

                //Declare Variables and provide values
                string FileNamePart = "Customer";//Datetime will be added to it
                string DestinationFolder = @"C:\Destination\";
                string TableName = "Dbo.Customer";
                string FileDelimiter = ","; //You can provide comma or pipe or whatever you like
                string FileExtension = ".txt"; //Provide the extension you like such as .txt or .csv


                //Create Connection to SQL Server in which you like to load files
                SqlConnection SQLConnection = new SqlConnection();
                    SQLConnection.ConnectionString = "Data Source = (local); Initial Catalog =TechBrothersIT; "
                       + "Integrated Security=true;";

                //Read data from table or view to data table
                string query = "Select * From " + TableName;
                SqlCommand cmd = new SqlCommand(query, SQLConnection);
                SQLConnection.Open();
                DataTable d_table = new DataTable();
                d_table.Load(cmd.ExecuteReader());
                SQLConnection.Close();

                //Prepare the file path 
                string FileFullPath = DestinationFolder + "\\" + FileNamePart + "_" + datetime + FileExtension;

                StreamWriter sw = null;
                sw = new StreamWriter(FileFullPath, false);

                // Write the Header Row to File
                int ColumnCount = d_table.Columns.Count;
                for (int ic = 0; ic < ColumnCount; ic++)
                {
                    sw.Write(d_table.Columns[ic]);
                    if (ic < ColumnCount - 1)
                    {
                        sw.Write(FileDelimiter);
                    }
                }
                sw.Write(sw.NewLine);

                // Write All Rows to the File
                foreach (DataRow dr in d_table.Rows)
                {
                    for (int ir = 0; ir < ColumnCount; ir++)
                    {
                        if (!Convert.IsDBNull(dr[ir]))
                        {
                            sw.Write(dr[ir].ToString());
                        }
                        if (ir < ColumnCount - 1)
                        {
                            sw.Write(FileDelimiter);
                        }
                    }
                    sw.Write(sw.NewLine);

                }

                sw.Close();
             
            }
            catch (Exception exception)
            {
                // Create Log File for Errors
                using (StreamWriter sw = File.CreateText(LogFolder
                    + "\\" + "ErrorLog_" + datetime + ".log"))
                {
                    sw.WriteLine(exception.ToString());
                   
                }

            }

        }
    }
}

I executed the program couple of times and Customer file was created as shown below.

How to create Text file from SQL Server Table or View in C#