C# 我正试图从网站下载图像，但图像的url'；s不工作为什么？

代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;
using System.Text.RegularExpressions;
using System.IO;
using unfreez_wrapper;
using Shell32;


namespace DownloadImages
{
    public partial class Form1 : Form
    {
        string f;
        string UrlsPath;
        int counter;
        UnFreezWrapper uf;
        string localFilename;

        public Form1()
        {
            InitializeComponent();

            uf = new UnFreezWrapper();
            counter = 0;
            localFilename = @"d:\localpath\";
            UrlsPath = @"d:\localpath\Urls\";

                using (WebClient client = new WebClient())
                {
                    client.DownloadFile("http://www.sat24.com/foreloop.aspx?type=1&continent=europa#",localFilename + "test.html");
                    client.DownloadFile("http://www.sat24.com/en/eu?ir=true", localFilename + "test1.html");
                }

                f = File.ReadAllText(localFilename + "test1.html");
                test("image2.ashx", "ir=true");
        }

        private void test(string firstTag, string lastTag)
        {
            List<string> imagesUrls = new List<string>();
            int startIndex = 0;
            int endIndex = 0;
            int position = 0;

            string startTag = firstTag;//"http://www.niederschlagsradar.de/images.aspx";
            string endTag = lastTag;//"cultuur=en-GB&continent=europa";

            startIndex = f.IndexOf(startTag);

            while (startIndex > 0)
            {

                endIndex = f.IndexOf(endTag,startIndex);
                if (endIndex == -1)
                {
                    break;
                }
                string t = f.Substring(startIndex, endIndex - startIndex + endTag.Length);
                imagesUrls.Add(t);
                position = endIndex + endTag.Length;
                startIndex = f.IndexOf(startTag,position);
            }
            string item = imagesUrls[imagesUrls.Count - 1];
            imagesUrls.Remove(item);
            for (int i = 0; i < imagesUrls.Count; i++)
            {
                using (WebClient client = new WebClient())
                {
                    client.DownloadFile(imagesUrls[i], UrlsPath + "Image" + counter.ToString("D6"));
                }
                counter++;
            }
            List<string> files = Directory.GetFiles(UrlsPath).ToList();
            uf.MakeGIF(files, localFilename + "weather", 80, true);
        }

在列表中：imagesUrls我看到这9个URL：

例如，这在索引0中：image2.ashx？region=eu&time=201309162345&ir=true 我试过不用image2.ashx？ 但在这两种情况下，我都会遇到一个错误：

client.DownloadFile(imagesUrls[i], UrlsPath + "Image" + counter.ToString("D6"));

论据例外 路径中的非法字符

在此之前，当我使用test.html和另外两个标记start和end时，它工作起来没有任何问题

但是现在我使用test1.html和这两个标签：test（“image2.ashx”，“ir=true”）； 但是得到了例外

当我以一个图像url为例：image2.ashx？region=eu&time=201309170015&ir=true 并试图在chrome上冲浪，但没有收到任何结果，它试图在谷歌上搜索

它甚至不是一个url

这是完整的异常错误：

System.ArgumentException was unhandled
  HResult=-2147024809
  Message=Illegal characters in path.
  Source=mscorlib
  StackTrace:
       at System.IO.Path.CheckInvalidPathChars(String path, Boolean checkAdditional)
       at System.Security.Permissions.FileIOPermission.CheckIllegalCharacters(String[] str)
       at System.Security.Permissions.FileIOPermission.AddPathList(FileIOPermissionAccess access, AccessControlActions control, String[] pathListOrig, Boolean checkForDuplicates, Boolean needFullPath, Boolean copyPathList)
       at System.Security.Permissions.FileIOPermission..ctor(FileIOPermissionAccess access, String[] pathList, Boolean checkForDuplicates, Boolean needFullPath)
       at System.IO.Path.GetFullPath(String path)
       at System.Net.WebClient.GetUri(String path)
       at System.Net.WebClient.DownloadFile(String address, String fileName)
       at DownloadImages.Form1.test(String firstTag, String lastTag) in d:\C-Sharp\DownloadImages\DownloadImages\DownloadImages\Form1.cs:line 79
       at DownloadImages.Form1..ctor() in d:\C-Sharp\DownloadImages\DownloadImages\DownloadImages\Form1.cs:line 45
       at DownloadImages.Program.Main() in d:\C-Sharp\DownloadImages\DownloadImages\DownloadImages\Program.cs:line 19
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: 

那么我如何从这个url一个接一个地下载图片呢

当我使用test.html和startTag“：和endTag:“cultuur=en-GB&containment=europa”时 它工作得很好

---

但是现在使用test1.html和两个不同的标签是不起作用的。

在异常点，imagesUrls[i]中到底是什么

你是说它类似于

image2.ashx？region=eu&time=201309162345&ir=true

如果是这样，您需要预先添加协议和服务器，即预先添加

http://www.sat24.com/

给出

http://www.sat24.com/image2.ashx?region=eu&time=201309162345&ir=true

但是，另一个问题是，您正在搜索

image2.ashx

作为开始标记，然后搜索

ir=true

作为结束标记。查看该页面的源代码，有许多

image2.ashx

URI没有以

ir=true

结尾

e、 g.

http://www.sat24.com/image2.ashx?button=af260x160

---

当您在该URI中找到开始标记时，您将在找到结束标记之前获得大量HTML。

问题在于图像url不是真实的url。因此，如何在该动画中找到每个图像url？

System.ArgumentException was unhandled
  HResult=-2147024809
  Message=Illegal characters in path.
  Source=mscorlib
  StackTrace:
       at System.IO.Path.CheckInvalidPathChars(String path, Boolean checkAdditional)
       at System.Security.Permissions.FileIOPermission.CheckIllegalCharacters(String[] str)
       at System.Security.Permissions.FileIOPermission.AddPathList(FileIOPermissionAccess access, AccessControlActions control, String[] pathListOrig, Boolean checkForDuplicates, Boolean needFullPath, Boolean copyPathList)
       at System.Security.Permissions.FileIOPermission..ctor(FileIOPermissionAccess access, String[] pathList, Boolean checkForDuplicates, Boolean needFullPath)
       at System.IO.Path.GetFullPath(String path)
       at System.Net.WebClient.GetUri(String path)
       at System.Net.WebClient.DownloadFile(String address, String fileName)
       at DownloadImages.Form1.test(String firstTag, String lastTag) in d:\C-Sharp\DownloadImages\DownloadImages\DownloadImages\Form1.cs:line 79
       at DownloadImages.Form1..ctor() in d:\C-Sharp\DownloadImages\DownloadImages\DownloadImages\Form1.cs:line 45
       at DownloadImages.Program.Main() in d:\C-Sharp\DownloadImages\DownloadImages\DownloadImages\Program.cs:line 19
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: