CODEWITHSUNDEEP
c#windows-8http-headers
Norbert Pisz
Norbert Pisz

Reputation: 3440

HttpClient Request like browser

When I calling site www.livescore.com by HttpClient class I always getting error "500". Probably server blocked request from HttpClients.

1)There is any other method to get html from webpage?

2)How I can set the headers to get html content?

When I set headers like in browser I always get stange encoded content.

    http_client.DefaultRequestHeaders.TryAddWithoutValidation("Accept", "text/html,application/xhtml+xml,application/xml");
    http_client.DefaultRequestHeaders.TryAddWithoutValidation("Accept-Encoding", "gzip, deflate");
    http_client.DefaultRequestHeaders.TryAddWithoutValidation("User-Agent", "Mozilla/5.0 (Windows NT 6.2; WOW64; rv:19.0) Gecko/20100101 Firefox/19.0");
    http_client.DefaultRequestHeaders.TryAddWithoutValidation("Accept-Charset", "ISO-8859-1");

3) How I can slove this problem? Any suggestions?

I using Windows 8 Metro Style App in C# and HttpClientClass

Upvotes: 40

Views: 57448

Answers (4)

Jesse C. Slicer
Jesse C. Slicer

Reputation: 20157

Here you go - note you have to decompress the gzip encoded-result you get back as per mleroy:

private static readonly HttpClient _HttpClient = new();

private static async Task<string> GetResponse(string url, CancellationToken token = default)
{
    using var request = new HttpRequestMessage(HttpMethod.Get, new Uri(url));
    request.Headers.TryAddWithoutValidation("Accept", "text/html,application/xhtml+xml,application/xml");
    request.Headers.TryAddWithoutValidation("Accept-Encoding", "gzip, deflate");
    request.Headers.TryAddWithoutValidation("User-Agent", "Mozilla/5.0 (Windows NT 6.2; WOW64; rv:19.0) Gecko/20100101 Firefox/19.0");
    request.Headers.TryAddWithoutValidation("Accept-Charset", "ISO-8859-1");

    using var response = await _HttpClient.SendAsync(request, token).ConfigureAwait(false);
    response.EnsureSuccessStatusCode();
    await using var responseStream = await response.Content.ReadAsStreamAsync(token).ConfigureAwait(false);
    await using var decompressedStream = new GZipStream(responseStream, CompressionMode.Decompress);
    using var streamReader = new StreamReader(decompressedStream);
    return await streamReader.ReadToEndAsync(token).ConfigureAwait(false);
}

call such like:

var response = await GetResponse("http://www.livescore.com/").ConfigureAwait(false); // or var response = GetResponse("http://www.livescore.com/").Result;

Upvotes: 73

user3285954
user3285954

Reputation: 4729

Could try this as well to add compression support: 

var compressclient = new HttpClient(new HttpClientHandler() 
{ 
AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip 
});

This adds the headers too.

According to the same thread support is now in Windows Store framework: http://social.msdn.microsoft.com/Forums/windowsapps/en-US/429bb65c-5f6b-42e0-840b-1f1ea3626a42/httpclient-data-compression-and-caching?prof=required

Upvotes: 26

siger
siger

Reputation: 3162

Several things to take note of.

  1. That site requires you to provide a user agent, or it returns a 500 HTTP error.

  2. A GET request to livescore.com responds with a 302 to livescore.us. You need to handle the redirection or directly request livescore.us

  3. You need to decompress a gzip-compressed response

This code works using the .NET 4 Client Profile, I'll let you figure out if it fits a Windows Store app.

var request = (HttpWebRequest)HttpWebRequest.Create("http://www.livescore.com");
request.AllowAutoRedirect = true;
request.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.57 Safari/537.17";

string content;

using (var response = (HttpWebResponse)request.GetResponse())
using (var decompressedStream = new GZipStream(response.GetResponseStream(), CompressionMode.Decompress))
using (var streamReader = new StreamReader(decompressedStream))
{
    content = streamReader.ReadToEnd();
}

Upvotes: 5

markoo
markoo

Reputation: 738

I think you can be pretty certain that they have done everything to stop developers from screen-scraping.

If I try from a standard C# project using this code :

  var request = WebRequest.Create("http://www.livescore.com ");
  var response = request.GetResponse();

I get this response:

The remote server returned an error: (403) Forbidden.

Upvotes: 1

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