使用PHP Simple HTML DOM Parser提取指定div内容遇阻，求解决方案

Hey there! Let's break down why your code isn't entering the foreach loop and how to extract that (+2.28%) value properly.

The Root Cause of Your Issue #

Your current selector div[n_changetext] is looking for <div> elements that have an attribute named n_changetext — but your target element has an id attribute set to b_changetext. That mismatch means the parser can't find any matching elements, so the loop never runs.

Step 1: Fix the Selector to Enter the Loop #

To target the correct <div>, use the id selector (since ids are unique, you can even skip the loop and grab the element directly):

// Option 1: Using id selector with foreach (though loop is unnecessary for unique id)
foreach($html->find('div#b_changetext') as $e){ 
    echo $e->innertext . '<br>'; 
    echo "wwwwww"; // This will now show up!
}

// Option 2: Grab the element directly (better for unique ids)
$targetDiv = $html->find('div#b_changetext', 0);
if ($targetDiv) {
    echo $targetDiv->innertext . '<br>';
    echo "wwwwww";
}

Step 2: Extract the (+2.28%) Value #

The innertext includes the <span> content too, so we need to isolate just the percentage text. Here are two reliable methods:

Method 1: Use Plain Text + Regular Expression

Grab the plain text of the div and match the parenthesized percentage:

$targetDiv = $html->find('div#b_changetext', 0);
if ($targetDiv) {
    $fullText = $targetDiv->plaintext;
    // Match any text inside parentheses
    preg_match('/\([^)]+\)/', $fullText, $matches);
    if (!empty($matches)) {
        echo $matches[0]; // Outputs: (+2.28%)
    }
}

Method 2: Target the Text Node Directly

The percentage is a direct text child of the div. We can loop through the div's nodes to find the text node:

$targetDiv = $html->find('div#b_changetext', 0);
if ($targetDiv) {
    foreach ($targetDiv->nodes as $node) {
        // Node type 3 = text node
        if ($node->nodetype === 3) {
            $percentage = trim($node->text);
            echo $percentage; // Outputs: (+2.28%)
            break; // Stop after finding the first text node
        }
    }
}

Key Takeaway #

Always double-check your selectors: use #id for id attributes, .class for classes, and [attribute="value"] only when targeting custom or non-id/class attributes.

内容的提问来源于stack exchange，提问作者kiranshiv