如何修复System.Net.WebException：'文件名，目录名或卷标签语法不正确

Question

I am trying to create a bootstrapper for a program and the error "System.Net.WebException: 'The filename, directory name, or volume label syntax is incorrect " Keeps popping up.

I have been stuck on this problem and have been guessing how to solve the problem.

String pname = "Fredysploit_v2";
String dlink = "https://pastebin.com/V5NcE09n";
string title = @"Title ";
Console.Title = pname + " Bootstrapper";

Console.ForegroundColor = ConsoleColor.Blue;
Console.ForegroundColor = ConsoleColor.Cyan;
Console.WriteLine(title);
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine("Downloading new Files...");
WebClient wc = new WebClient();
string key = wc.DownloadString(dlink);
string path = @"Update\" + pname + ".exe";
System.Net.WebClient Dow = new WebClient();
string patch = (@"Update");
Directory.CreateDirectory(patch);
//My problem ↓
Dow.DownloadFile(key, path);
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine(pname + " Downloaded | Updated!");
Console.WriteLine($"Now open " + patch + " and Run " + pname + ".exe");
Console.ReadKey();

I expected the outcome to download the file off the text which is a link on pastebin but, the actual outcome was "System.Net.WebException: 'The filename, directory name, or volume label syntax is incorrect".

Answer 1

I think what's happening is that you try to download the entire website as a file and not downloading the file linked in your pastebin content ( proof here ).

Maybe there is a way to obtain the link, like: parsing the html of the website and reading the content from a specific html tag or, if existing, using the pastebin api (I will check on that one now. There is a pastebin api . Maybe take a look at this)

---

Since the api isn't helping you out very much, here is some code to parse HTML from a website: WebClient client = new WebClient(); String htmlCode = client.DownloadString(" https://pastebin.com/raw/dnfHuGAK "); WebClient client = new WebClient(); String htmlCode = client.DownloadString(" https://pastebin.com/raw/dnfHuGAK ");

This allows you to get the string inside the paste.

---

This will be your final change to your code and should fix your problem

    String pname = "Fredysploit_v2";
    String dlink = "https://pastebin.com/raw/dnfHuGAK"; 
    //^ changed the download link to the raw paste so you can extract your link
    string title = @"Title ";
    Console.Title = pname + " Bootstrapper";

    Console.ForegroundColor = ConsoleColor.Blue;
    Console.ForegroundColor = ConsoleColor.Cyan;
    Console.WriteLine(title);
    Console.ForegroundColor = ConsoleColor.Green;
    Console.WriteLine("Downloading new Files...");
    WebClient wc = new WebClient();
    string key = wc.DownloadString(dlink);
    string path = @"Update\" + pname + ".exe";
    System.Net.WebClient Dow = new WebClient();
    string patch = (@"Update");
    Directory.CreateDirectory(patch);
    Dow.DownloadFile(key, path);
    Console.ForegroundColor = ConsoleColor.Green;
    Console.WriteLine(pname + " Downloaded | Updated!");
    Console.WriteLine($"Now open { patch } and Run { pname }.exe");
    //^ since you are using String.Format(), make use of it :)
    Console.ReadKey();

Answer 2

The problem is you are getting the entire page of HTML form pastebin not the URL you are looking for. As @Jon Skeet mentioned in comments, try using https://pastebin.com/raw/V5NcE09n as dlink so it shows as follows:

String dlink = "https://pastebin.com/raw/V5NcE09n";

The updated code solution is below:

String pname = "Fredysploit_v2";
String dlink = "https://pastebin.com/raw/V5NcE09n";
string title = @"Title ";
Console.Title = pname + " Bootstrapper";

Console.ForegroundColor = ConsoleColor.Blue;
Console.ForegroundColor = ConsoleColor.Cyan;
Console.WriteLine(title);
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine("Downloading new Files...");
WebClient wc = new WebClient();
string key = wc.DownloadString(dlink);
string path = @"Update\" + pname + ".exe";
System.Net.WebClient Dow = new WebClient();
string patch = (@"Update");
Directory.CreateDirectory(patch);

Dow.DownloadFile(key, path);
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine(pname + " Downloaded | Updated!");
Console.WriteLine($"Now open " + patch + " and Run " + pname + ".exe");
Console.ReadKey();