Resume Support for File Downloads

using System;
using System.Collections.Generic;
using System.Text;

namespace DownloaderBase
{
    class Program
    {
        static System.Collections.Specialized.NameValueCollection q;
        static void Main(string[] args)
        {
            if (args != null)
            {
                if (args.Length > 0)
                {
                    q = new System.Collections.Specialized.NameValueCollection();
                    try
                    {
                        //Console.WriteLine(args[0]);
                        //Console.ReadKey();
                        //return;

                        SetArguments(args[0]);
                        DownloadFile();
                        Console.ReadKey();
                        return;
                    }
                    catch (Exception eXc)
                    {
                        Console.WriteLine("Error :" + eXc.Message);
                        Console.WriteLine("Stack :" + eXc.StackTrace);
                    }
                    
                }
            }
            StringBuilder sb = new StringBuilder();
            sb.AppendLine("Call with Arguments");
            sb.AppendLine("");
            sb.AppendLine("");
            sb.AppendLine("srcUrl: Source URL Path");
            sb.AppendLine("");
            sb.AppendLine("");
            sb.AppendLine("DestPath: Destination File Path Where it to Save");
            Console.WriteLine(sb.ToString());
            Console.ReadKey();
        }
        static void SetArguments(string sArguments)
        {
            string[] sArgs = sArguments.Split(new string[] { "/:" }, StringSplitOptions.RemoveEmptyEntries);
            int iDx = 0;
            foreach (string ss in sArgs)
            {
                iDx++;
                string[] sVl = ss.Split('=');
                q.Add(sVl[0], sVl[1]);                
            }
        }
        static void DownloadFile()
        {
            
            string sDest= q["DestPath"];
            string sUrl = q["srcUrl"];
            Console.WriteLine("Destination Path :" + sDest);
            Console.WriteLine("Source File Path :" + sUrl);

            DownloadFile(sUrl, sDest);

        }
        
        static void DownloadFile(string sSourceURL, string sDestinationPath)
        {
            long iFileSize = 0;
            int iBufferSize = 1024;
            iBufferSize *= 1000;
            long iExistLen = 0;
            System.IO.FileStream saveFileStream;
            if (System.IO.File.Exists(sDestinationPath))
            {
                System.IO.FileInfo fINfo = new System.IO.FileInfo(sDestinationPath);
                iExistLen = fINfo.Length;
            }
            if (iExistLen > 0)
                saveFileStream = new System.IO.FileStream(sDestinationPath, System.IO.FileMode.Append, System.IO.FileAccess.Write, System.IO.FileShare.ReadWrite);
            else
                saveFileStream = new System.IO.FileStream(sDestinationPath, System.IO.FileMode.Create, System.IO.FileAccess.Write, System.IO.FileShare.ReadWrite);



            System.Net.HttpWebRequest hwRq;
            System.Net.HttpWebResponse hwRes;
            hwRq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(sSourceURL);
            hwRq.AddRange((int)iExistLen);
            System.IO.Stream smRespStream;
            hwRes = (System.Net.HttpWebResponse)hwRq.GetResponse();
            smRespStream = hwRes.GetResponseStream();

            iFileSize = hwRes.ContentLength;

            int iByteSize;
            byte[] downBuffer = new byte[iBufferSize];

            while ((iByteSize = smRespStream.Read(downBuffer, 0, downBuffer.Length)) > 0)
            {
                saveFileStream.Write(downBuffer, 0, iByteSize);
            }



        }

    }
}