Combine CSV Files using C#

The simple script below shows how to combine csv files without duplicating headings using C#. This technique assumes that all of the files have the same structure, and that all of them contain a header row.

using System.IO;
using System.Linq;

namespace CombineCsvFiles
{
    class Program
    {
        static void Main(string[] args)
        {
            var sourceFolder = @"C:\csv_files";
            var destinationFile = @"C:\csv_files\csv_files_combined.csv";

            // Wildcard search returns files with 1-2 digit suffix
            string[] filePaths = Directory.GetFiles(sourceFolder, "csv_file_??.csv");
            StreamWriter fileDest = new StreamWriter(destinationFile, true);

            int i;
            for (i = 0; i < filePaths.Length; i++)
            {
                var file = filePaths[i];
                string[] lines = File.ReadAllLines(file);

                // Skip header row for all but first file
                if (i > 0)
                {
                    lines = lines.Skip(1).ToArray();
                }

                foreach (var line in lines)
                {
                    fileDest.WriteLine(line);
                }
            }

            fileDest.Close();
        }
    }
}