[英]DownloadFileAsync multiple files using webclient
Description 描述
Download multiple files using webclient's DownloadFileAsync and utilizing a text file for URL input for download. 使用webclient的DownloadFileAsync下载多个文件,并使用文本文件进行URL输入下载。
Problem 问题
The approach that I have used won't download files at all. 我使用的方法根本不会下载文件。 Just runs and does nothing.
只是跑步而且什么都不做。 It fills the list array then quits the program without downloading a single file.
它填充列表数组然后退出程序而不下载单个文件。 I have googled for solutions but come up shorthanded.
我已经google了解决方案,但缺乏信心。 Then attempted to search for a solution in the database here with same results.
然后尝试在此处搜索数据库中的解决方案,结果相同。 Any help is appreciated.
任何帮助表示赞赏。
Questions 问题
Code 码
DownloadClass.cs DownloadClass.cs
using System;
using System.ComponentModel;
using System.Collections.Generic;
using System.Net;
using System.Threading;
using System.Windows.Forms;
namespace ThreadTest
{
class DownloadClass
{
public struct download
{
public static string URL { get; set; }
public static string file { get; set; }
public static string[] link;
public static int downloadcount;
}
public static List<string> list = new List<string>();
public static WebClient wc = new WebClient();
public static void Download()
{
int count = 0;
download.URL = list[0];
Uri URI = new Uri(download.URL);
UriBuilder uri = new UriBuilder(URI);
download.link = uri.Path.ToLower().Split(new char[] { '/' });
count = 0;
// Find file
foreach (string abs in download.link)
{
count++;
if (abs.ToLower().Contains(".html") || abs.ToLower().Contains(".exe") || abs.ToLower().Contains(".txt"))
{
try
{
download.file = download.link[count];
wc.Proxy = null;
wc.DownloadFileCompleted += new AsyncCompletedEventHandler(wc_DownloadFileCompleted);
wc.DownloadFileAsync(URI, Application.StartupPath + "\\" + download.file);
break;
}
catch (Exception)
{ }
}
}
}
public static void BeginDownload()
{
new Thread(Download).Start();
}
public static void wc_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
{
int count = 0;
download.downloadcount++;
download.URL = list[0];
Uri URI = new Uri(download.URL);
UriBuilder uri = new UriBuilder(URI);
download.link = uri.Path.ToLower().Split(new char[] { '/' });
count = 0;
// Find file
foreach (string abs in download.link)
{
count++;
if (abs.ToLower().Contains(".html") || abs.ToLower().Contains(".exe") || abs.ToLower().Contains(".txt"))
{
try
{
download.file = download.link[count];
}
catch (Exception)
{ }
}
}
list.RemoveAt(0);
if (list.Count > 0)
{
wc.DownloadFileAsync(URI, list[download.downloadcount], Application.StartupPath + "\\" + download.file);
}
else
{
Console.WriteLine("Downloading is done.");
Environment.Exit(0);
}
}
}
}
Program.cs (Main Class) Program.cs(主类)
using System;
using System.IO;
using System.Collections.Generic;
using System.Windows.Forms;
namespace ThreadTest
{
class Program
{
static void Main(string[] args)
{
if (args.Length < 1)
{
Console.WriteLine("Usage: {0} <download txtfile>", Environment.GetCommandLineArgs()[0]);
Environment.Exit(0);
}
int counter = 0;
string line;
string format = string.Format("{0}\\{1}", Application.StartupPath, args[0]);
// Read the file line by line.
using(StreamReader file = new StreamReader(format))
{
while ((line = file.ReadLine())!= null)
{
// Store urls in a list.
DownloadClass.list.Add(line);
counter++;
}
}
DownloadClass.BeginDownload();
}
}
}
Besides being bad design there are lots of issues that lead to your code not (or nor correctly working). 除了糟糕的设计之外,还有许多问题会导致您的代码无法(或者无法正常工作)。
As long as you have no knowledge about multithreading I'd recommend you use the synchoneous methods to avoid all those problems. 只要您不了解多线程,我建议您使用同步方法来避免所有这些问题。
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