Sync/Parallel/Async file download

Downloads.cs

using System;
using System.Linq;
using System.Net;
using System.Threading.Tasks;

namespace Downloads {
    class Program {

        static void Main(string[] args) {
            var urls = new string[] {
                "https://www.aspnet.cz/",
                "https://www.rider.cz/",
                "https://www.vlcak.cz/",
                "https://www.wolfcult.cz/"
            };

            // Sync
            Console.WriteLine("Downloading synchronously:");
            var sw = new System.Diagnostics.Stopwatch();
            sw.Start();
            foreach (var url in urls) {
                DownloadUrl(url);
            }
            sw.Stop();
            Console.WriteLine($"Done in {sw.ElapsedMilliseconds} ms");

            // Parallel
            Console.WriteLine("Downloading parallel:");
            sw.Restart();
            Parallel.ForEach(urls, url => {
                DownloadUrl(url);
            });
            sw.Stop();
            Console.WriteLine($"Done in {sw.ElapsedMilliseconds} ms");

            // Async
            Console.WriteLine("Downloading async:");
            sw.Restart();
            var tasks = urls.Select(url => DownloadUrlAsync(url)).ToArray();
            Task.WaitAll(tasks);
            sw.Stop();
            Console.WriteLine($"Done in {sw.ElapsedMilliseconds} ms");
        }

        public static async Task DownloadUrlAsync(string url) {
            using (var wc = new WebClient()) {
                Console.WriteLine($"  Started {url}...");
                var s = await wc.DownloadDataTaskAsync(url);
                Console.WriteLine($"  Finished {url}, {s.Length} bytes...");
            }
        }

        public static void DownloadUrl(string url) {
            using (var wc = new WebClient()) {
                Console.WriteLine($"  Started {url}...");
                var s = wc.DownloadData(url);
                Console.WriteLine($"  Finished {url}, {s.Length} bytes...");
            }
        }

    }
}

How to handle completion?? I mean

wc->DownloadFile(url,path+"name.exe");