PHP - 从字符串中提取值

Question

我有几个字符串已从另一个网站使用cURL提取。该字符串包含整个页面的HTML结构，但每一个页面里面有概述如下段落：

<p>Displaying 1-15 of 15 items beginning with A</p>
<p>Displaying 1-20 of 33 items beginning with B</p>

我需要做的只是从这些字符串中提取的总价值（15在上述情况下为33）。

我不确定提取值的最佳方法是什么。

谢谢:)

Answer 1

蛮力方法：

http://php.net/manual/en/function.preg-match-all.php

preg_match_all('/<p>Displaying (\d+)-(\d+) of (\d+) items beginning with ([A-Z]+)</p>/', $subject, $matches); 

Answer 2

创建一个正则表达式;

$regex = "/Displaying 1-([0-9]+) of ([0-9]+) items begginning with/"; 
preg_match($regex,$resultfromcurl,$match); 

是这样的吗？

Answer 3

可能会迟到一天，但是这里是我的2美分：这将解析文件中的html，抓取段落，找到匹配，并将所有相关值放入数组中使用。

<?php 

// Open your document 
$doc = new DOMDocument(); 

// Parse the HTML 
$doc->loadHTMLFile("html_doc.html"); 

// Find the paragraphs and loop through them 
$paras = $doc->getElementsByTagName('p'); 

// Initialize value array 
$range = array(); 

// Extract the value and put them in a useful data structure 
for ($i = 0; $i < $paras->length; $i++) { 
    $subject = $paras->item($i)->nodeValue; 
    preg_match('/Displaying (\d+)-(\d+) of (\d+) items beginning with ([A-Z]+)/', $subject, $matches); 
    $range[$matches[4]] = array(
     'start' => $matches[1], 
     'stop' => $matches[2], 
     'total' => $matches[3] 
    ); 
} 

foreach ($range as $begin => $values) { 
    echo "\n$begin\n"; 
    echo "start: " . $values['start'] . "\n"; 
    echo "stop: " . $values['stop'] . "\n"; 
    echo "total: " . $values['total'] . "\n"; 
    echo "------\n"; 
}