下载多个文件WebClient

Question

我正在尝试下载多个文件,但它没有像我希望的那样工作.有人可以告诉我这个剧本有什么问题,因为我已经尝试了很多东西而且真的不知道该怎么做了.

public static void DownloadFile(string url)
        {
            WebClient client = new WebClient();
            var name = url.Substring(url.LastIndexOf('/')).Remove(0, 1);
            foreach (var item in urls)
            {
                client.DownloadFile(item, "C:\\" + name);
            }
        }

        private void btnGo_Click(object sender, EventArgs e)
        {
            urls.Add("url1");
            urls.Add("url2");
            urls.Add("url3");
            Parallel.ForEach(urls,
               new ParallelOptions { MaxDegreeOfParallelism = 10 }, 
               DownloadFile);
        }

---

using (var sr = new StreamReader(HttpWebRequest.Create(url).GetResponse().GetResponseStream()))
            {
                using (var sw = new StreamWriter(url.Substring(url.LastIndexOf('/'))))
                {
                    sw.Write(sr.ReadToEnd());
                }
            }

Answer 1

我会System.Net.HttpWebRequest改用.

这就是代码的样子:

private List<string> urls = new List<string>();

private void btnGo_Click(object sender, EventArgs e)
{
    urls.Add("http://199.91.152.106/ua0p3fbc5nlg/gg2w2fq4ljc1nnd/MicroCraft_Beta.zip");
    Parallel.ForEach(urls, new ParallelOptions { MaxDegreeOfParallelism = 10 }, DownloadFile);
}

public static void DownloadFile(string url)
{
    var req = (HttpWebRequest)WebRequest.Create(url);
    var name = url.Substring(url.LastIndexOf('/') + 1);
    using (var res = (HttpWebResponse)req.GetResponse())
    using (var resStream = res.GetResponseStream())
    using (var fs = new FileStream("C:\\" + name, FileMode.Create, FileAccess.Write, FileShare.None))
    {
        // Save to file
        var buffer = new byte[8 * 1024]; // 8 KB buffer
        int len; // Read count
        while ((len = resStream.Read(buffer, 0, buffer.Length)) > 0)
            fs.Write(buffer, 0, buffer.Length);
    }
}

因为您在评论中告诉我的URL没有使用HTTP协议的正确实现.您必须将其添加到您的配置文件才能使其工作(App.config或Web.config,具体取决于它是ASP.Net站点还是脱机应用程序):

<system.net>
    <settings>
        <httpWebRequest useUnsafeHeaderParsing="true" />
    </settings>
</system.net>

至于你在评论中提到的名字冲突问题,应该通过将你var name = url.Substring(url.LastIndexOf('/')).Remove(0, 1);改成别的东西来解决.

如果您想拥有增量文件名,可以使用:

// Inside your class:
private static int counter = 0;

// In your method:
var name = "file" + System.Threading.Interlocked.Increment(ref counter) + ".html";