PHP Crawl Website: Simple DOM Parsing Collection Example

First, why use a proxy IP to engage in web crawling?

The old iron who has engaged in data collection knows that many websites have installed theanti-crawler mechanismIt's like a neighborhood access control, where the same IP must be blocked from entering and exiting frequently. At this time it is necessary to change like a vest, with a different proxy IP toDecentralization of request pressureOur ipipgo service is specialized in solving this pain point. Our ipipgo service is specialized in solving this pain point, as if the crawler installed a "transient skills", each time you visit can change a new IP address.

Second, hand to teach you to use PHP to play around with DOM parsing

Let's start with the whole simple-to-cry example, let's use thegrocery shoppingto analogy: assuming that to capture the price of a site's goods, as in the market stall by stall to ask the price. Here we recommend using PHP comes with DOMDocument, do not have to install additional plug-ins, white people can also immediately get started.

loadHTML(file_get_contents($url, false, stream_context_create([
    'http' => ['proxy' => 'tcp://'.$proxy, 'timeout' => 30]
]))));

$prices = $dom->getElementsByTagName('span');
foreach ($prices as $node) {
    if ($node->getAttribute('class') === 'price') {
        echo $node->nodeValue."";
    }
}
? >

Third, the correct opening posture of the proxy IP

The point is coming! A lot of newbies plant themselves on proxy settings, so here's the kicker:

It is recommended to add aIP Pool Recycling MechanismIt's like this:

// Get 10 IPs from ipipgo and store them in an array
$ipPool = json_decode(file_get_contents('https://api.ipipgo.com/batch?count=10'));

IV. Practical guide to avoiding pitfalls

Ever been in one of these situations?

• Incomplete page load → check if JS rendering is triggered
• Data Misalignment → XPath instead of class selection
• Suddenly blocked IP → immediately switch ipipgoemergency standby channel

It is recommended that exception handling be added:

try {
    // Capture code
} catch (Exception $e) {
    $proxy = ipipgo::getNewProxy(); // Automatically change to the new IP
    retry(); }
}

V. Frequently Asked Questions QA

Q: Is it okay to use a free proxy?
A: Don't save this money! Free proxies are like public restrooms, anyone can use them, they are slow and insecure. ipipgoexclusive IP poolSupports millions of requests per day and stability hanging free proxies.

Q：When collecting, it always returns a blank page?
A: Ninety percent of the IP was blacked out, hurry to ipipgo backstageRefresh IP WhitelistIt is recommended to set the IP to change automatically every 50 requests.

Q: Do I need to simulate different regional IPs?
A: ipipgo supportCity-level positioningIf you want Beijing, Shanghai or Guangzhou IP, you can specify it by adding a location field to the API parameters.

VI. Why choose ipipgo?

Self-service must be blown out of the water! OurMedical-grade IP care systemThere are three masterpieces:

1. IP survival detection every 5 minutes
2. Automatic rejection of failed nodes
3. Support HTTP/HTTPS/SOCKS5 three protocols

A sneaky secret: use a coupon codePHP2024Can get 20% off, the official website price page directly lose it. Encounter technical problems directly to customer service, the response speed is faster than the delivery boy!