c# - Copy top n lines from text file

Below code does the same job of head command in Unix which is widely used to get the top n lines from a text file.

namespace PartialFileCopier

{

    class Program

    {

        static void Main(string[] args)

        {

            String sLine = String.Empty;

            Int32 iLineCounter = 0;

            Int32 iLineCount = Int32.Parse(ConfigurationSettings.AppSettings["LINE_COUNT"]);

            

            try

            {

                using (StreamWriter writer = new StreamWriter(ConfigurationSettings.AppSettings["OUTPUT_FILE_NAME"]))

                {

                    using (StreamReader reader = new StreamReader(ConfigurationSettings.AppSettings["INPUT_FILE_NAME"]))

                    {

                        while (!reader.EndOfStream )

                        {

                            sLine = reader.ReadLine();

                            iLineCounter++;

                            Console.WriteLine(sLine);

                            writer.WriteLine(sLine);

                            if (iLineCounter == iLineCount)

                                break;

                        }

                    }

                }

            }

            catch (Exception ex)

            {

                Console.WriteLine(ex.Message);

            }

            Console.Read();

        }

     }

}

The configuration entries

<?xml version="1.0" encoding="utf-8" ?>

<configuration>

  <appSettings>

    <add key="INPUT_FILE_NAME" value="\\Servername\InputFileName.txt"/>

    <add key="OUTPUT_FILE_NAME" value="\\Servername\OutputFileName.txt"/>

    <add key="LINE_COUNT" value="1000"/>

  </appSettings>

</configuration>