Proxy IP to realize C# website crawling: C# crawler configuration proxy IP program

Hands-on teaching you to use C to capture data when a proxy vest

Brothers who engage in data crawling know that the website anti-climbing mechanism is getting more and more refined. Recently, an e-commerce friend complained to me that the price monitoring program they wrote in C was always blocked by the target site IP, and they were anxious to jump straight to their feet. At this time, we have to sacrifice the proxy IP this magic weapon, to the crawler set a vest can continue to play happily.

How exactly do proxy IPs help C crawlers?

In a nutshell.Make the server think a different person is doing each requestIt's like when you go to the supermarket to buy cigarettes. Like you go to the supermarket to buy cigarettes, go three times in a row, the clerk must have remembered you, if each time to change different clothes and go again? Proxy IP is this dress-up technique.

Recommended hereipipgoThe proxy service, their family has a unique skill - dynamic residential IP. test down, with their proxy to catch an e-commerce platform, 200 consecutive requests have not triggered the blocking, more stable than the ordinary IP server room.

Three poses for configuring proxies in C

I've personally tripped over the pit with each of the following methods, and newbies are advised to look directly at the third one:

// Method 1: Traditional WebClient approach
var proxy = new WebProxy("proxy.ipipgo.io:8000");
proxy.Credentials = new NetworkCredential("Account", "Password"); var client = new WebClient { Proxy = proxy }; }
var client = new WebClient { Proxy = proxy };

// Method 2: Advanced play with HttpClient
var handler = new HttpClientHandler
var handler = new HttpClientHandler {
    Proxy = new WebProxy("http://proxy.ipipgo.io:8000"),
    UseProxy = true
}; var client = new HttpClientHandler { Proxy = new WebProxy("", UseProxy = true)
var client = new HttpClient(handler); var client = new HttpClient(handler); }

// Method 3: Switch proxies dynamically (recommended)
var proxyPool = new List { "ip1:port", "ip2:port", "ip3:port" }; // Pool of proxies from the ipipgo backend
var randomProxy = proxyPool[new Random().Next(proxyPool.Count)];
HttpClient.DefaultProxy = new WebProxy(randomProxy);

Guide to avoiding pitfalls: these details do not pay attention to is equal to a waste of engagement

Last week, I helped a customer debugging encountered a real case: obviously configured the proxy but still blocked. It was later found that the timeout time was not set, and the request got stuck, leading to IP exposure. Here are a few key points:

Practical QA: soul-crushing questions you might encounter

Q: Can't I just use a free proxy? Why do I need to buy ipipgo?
A: Last year, we tested the double 11, the average survival time of free agents less than 15 minutes, ipipgo agents survive 2 hours to start, the difference between the peak business is more obvious!

Q: What should I do if the proxy IP suddenly hangs?
A: Add a backup plan in the code to automatically call ipipgo's API to replace the IP pool when 3 consecutive requests fail

Q: How can I tell if a proxy is in effect?
A: Add a debug output in the code to print the actual IP used for each request, or directly access the live verification interface provided by ipipgo.

Upgrade Play: Intelligent Agent Scheduling System

Show the guys a program architecture we're using:

// Smart Proxy Scheduling Pseudo-Code
public string GetSmartProxy()
var availableProxies = GetFromIpipgoAPI()
    var availableProxies = GetFromIpipgoAPI(); // Get the latest proxies in real time.
    var location = GetTargetServerLocation(); // Select the proxy with the same location according to the target site
    return availableProxies.Where(p => p.Speed p.UsedCount).First();
}

This system with ipipgo's regional customized proxy can improve the collection efficiency by more than 40%. Especially when doing local life service data collection, using local IP can reduce the probability of being backcrawled.

Finally, the proxy IP is not a panacea, with a reasonable request frequency and Header camouflage. It is recommended to use ipipgo's pay-as-you-go package at the beginning, and run through the process first and then on the monthly service. If you have any specific questions, please feel free to come to our technical community to communicate with us, which is more practical than reading the documents.