多线程下载文件问题
0
悬赏园豆：50
[已解决问题]
解决于 2010-03-27 22:00
多线程下载的时候为什么有线程偷懒，只有两个线程在工作，如图我开启了5个线程，却只有0和3在工作。
代码
1 using System;
2 using System.Collections.Generic;
3 using System.Text;
4 using System.Drawing;
5 using System.Net;
6 using System.IO;
7 using System.Threading;
8
9 namespace ConsoleApplication9
10 {
11 class Program
12 {
13 static void Main(string[] args)
14 {
15
16
17 Thread[] ts = new Thread[5];
18 for (int i = 0; i < ts.Length; i++)
19 {
20 ts[i] = new Thread(new ThreadStart(down));
21 ts[i].Name = "线程 " + i.ToString();
22 ts[i].Start();
23
24 }
25 }
26
27 static int ran = 0;
28 static void down()
29 {
30 using (FileStream fs = new FileStream(Thread.CurrentThread.Name, FileMode.Create))
31 {
32 string url = "http://dl_dir.qq.com/qqfile/qq/QQ2010/QQ2010Beta2.exe";
33 HttpWebRequest req = WebRequest.Create(url) as HttpWebRequest;
34 req.AddRange(ran, ran + 1024 * 1024 * 10);
35 Stream stream = req.GetResponse().GetResponseStream();
36 byte[] buffer = new byte[256];
37 int i = stream.Read(buffer, 0, 256);
38 while (i > 0)
39 {
40 i = stream.Read(buffer, 0, 256);
41 Console.WriteLine(Thread.CurrentThread.Name);
42 fs.Write(buffer, 0, i);
43 Thread.Sleep(500);
44 }
45 }
46
47 }
48
49
50 }
51 }
问题2，如果我把下载方法改成下面这样，线程都不工作了，似乎是死锁？
这段代码的第7行是添加下载范围，如果没这段似乎就不出现此问题了，难道是ms的基础类锁定有问题吗
1
2 static int ran = 0;
3 static void down()
4 {
5 string url = "http://dl_dir.qq.com/qqfile/qq/QQ2010/QQ2010Beta2.exe";
6 HttpWebRequest req = WebRequest.Create(url) as HttpWebRequest;
7 req.AddRange(1,500000);
8 Stream stream = req.GetResponse().GetResponseStream();
9 byte[] buffer = new byte[256];
10 int i = stream.Read(buffer, 0, 256);
11 while (i > 0)
12 {
13 i = stream.Read(buffer, 0, 256);
14 }
15 }
错误如图（把项目暂停时查看变量值才知道线程都已经停了，可它们还没工作呢）
请高手帮忙解决下啊
问题补充：
上面代码直接复制会连行号也复制过去，所以看下面代码
第一部分源码
-------------------------------------
using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Net;
using System.IO;
using System.Threading;
namespace ConsoleApplication9
{
class Program
{
static void Main(string[] args)
{
Thread[] ts = new Thread[5];
for (int i = 0; i < ts.Length; i++)
{
ts[i] = new Thread(new ThreadStart(down));
ts[i].Name = "线程 " + i.ToString();
ts[i].Start();
}
}
static int ran = 0;
static void down()
{
using (FileStream fs = new FileStream(Thread.CurrentThread.Name, FileMode.Create))
{
string url = "http://dl_dir.qq.com/qqfile/qq/QQ2010/QQ2010Beta2.exe";
HttpWebRequest req = WebRequest.Create(url) as HttpWebRequest;
req.AddRange(ran, ran + 1024 * 1024 * 10);
Stream stream = req.GetResponse().GetResponseStream();
byte[] buffer = new byte[256];
int i = stream.Read(buffer, 0, 256);
while (i > 0)
{
i = stream.Read(buffer, 0, 256);
Console.WriteLine(Thread.CurrentThread.Name);
fs.Write(buffer, 0, i);
Thread.Sleep(500);
}
}
}
}
}
最佳答案
0
webrequest好像有并发线程数量的限制问题，是可以修改的，你试着改一下看看：）
收获园豆：50
