C# HttpClient Proxy Setup

C# HttpClient Proxy Integration

The .NET HttpClient supports proxies through HttpClientHandler and WebProxy. For production applications, IHttpClientFactory provides pooled, configurable clients with proxy support.

Basic Proxy Setup

using System.Net;

var proxy = new WebProxy("http://gate.hexproxies.com:8080")
{
    Credentials = new NetworkCredential("YOUR_USERNAME", "YOUR_PASSWORD")
};

var handler = new HttpClientHandler
{
    Proxy = proxy,
    UseProxy = true
};

var client = new HttpClient(handler)
{
    Timeout = TimeSpan.FromSeconds(30)
};

var response = await client.GetAsync("https://httpbin.org/ip");
var body = await response.Content.ReadAsStringAsync();
Console.WriteLine(
quot;Status: {response.StatusCode}");
Console.WriteLine(
quot;Body: {body}");

Sticky Sessions

var stickyProxy = new WebProxy("http://gate.hexproxies.com:8080")
{
    Credentials = new NetworkCredential(
        "YOUR_USERNAME-session-dotnet001",
        "YOUR_PASSWORD"
    )
};

IHttpClientFactory with Proxy (Dependency Injection)

// In Program.cs or Startup.cs
builder.Services.AddHttpClient("proxied", client =>
{
    client.Timeout = TimeSpan.FromSeconds(30);
})
.ConfigurePrimaryHttpMessageHandler(() =>
{
    var proxy = new WebProxy("http://gate.hexproxies.com:8080")
    {
        Credentials = new NetworkCredential(
            Environment.GetEnvironmentVariable("HEX_PROXY_USER"),
            Environment.GetEnvironmentVariable("HEX_PROXY_PASS")
        )
    };

    return new HttpClientHandler
    {
        Proxy = proxy,
        UseProxy = true
    };
});

// In a service class
public class ScrapingService
{
    private readonly HttpClient _client;

    public ScrapingService(IHttpClientFactory factory)
    {
        _client = factory.CreateClient("proxied");
    }

    public async Task<string> FetchAsync(string url)
    {
        var response = await _client.GetAsync(url);
        response.EnsureSuccessStatusCode();
        return await response.Content.ReadAsStringAsync();
    }
}

Retry with Polly

using Polly;
using Polly.Extensions.Http;

builder.Services.AddHttpClient("proxied")
    .ConfigurePrimaryHttpMessageHandler(() => new HttpClientHandler
    {
        Proxy = new WebProxy("http://gate.hexproxies.com:8080")
        {
            Credentials = new NetworkCredential("YOUR_USERNAME", "YOUR_PASSWORD")
        },
        UseProxy = true
    })
    .AddPolicyHandler(
        HttpPolicyExtensions
            .HandleTransientHttpError()
            .OrResult(r => r.StatusCode == (HttpStatusCode)429)
            .WaitAndRetryAsync(3, attempt => TimeSpan.FromSeconds(Math.Pow(2, attempt)))
    );

Concurrent Requests

var urls = new[]
{
    "https://httpbin.org/ip",
    "https://httpbin.org/headers",
    "https://httpbin.org/get"
};

var tasks = urls.Select(async url =>
{
    var resp = await client.GetAsync(url);
    var body = await resp.Content.ReadAsStringAsync();
    return (url, resp.StatusCode, body);
});

var results = await Task.WhenAll(tasks);
foreach (var (url, status, body) in results)
{
    Console.WriteLine(
quot;{url}: {status}");
}

SOCKS5 via SocketsHttpHandler (.NET 6+)

var handler = new SocketsHttpHandler
{
    Proxy = new WebProxy("socks5://gate.hexproxies.com:1080")
    {
        Credentials = new NetworkCredential("YOUR_USERNAME", "YOUR_PASSWORD")
    },
    UseProxy = true
};