Question

我在curl和xpath上有点新鲜，所以仍然在学习in's和out's。我写了一个刮刀但是当我试图通过一个阵列显示刮削数据时，没有任何东西出现。那我的代码有什么问题？

<?php

ini_set("display_errors", "1");
error_reporting(-1);
error_reporting(E_ERROR);
libxml_use_internal_errors(true);

//Basic Function
function get_url_contents($url, $timeout = 10, $userAgent = 'Mozilla/5.0(Macintosh; U; Intel Mac OS X 10_5_8; en-US)AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.215 Safari/534.10'){
    $rawhtml = curl_init();//handler
    curl_setopt($rawhtml, CURLOPT_URL,$url);//url
    curl_setopt($rawhtml, CURLOPT_RETURNTRANSFER, 1);//return result as string rahter than direct output
    curl_setopt($rawhtml, CURLOPT_CONNECTTIMEOUT,$timeout);//set timeout
    curl_setopt($rawhtml, CURLOPT_USERAGENT,$userAgent);//set user agent
    $output = curl_exec($rawhtml);//execute curl call
    curl_close($rawhtml);//close connection

    if(!$output){
        return -1;//if nothing obtained, return -1
    }
    return $output;
}

//get raw html
$html_string = get_url_contents("http://www.beursgorilla.nl/fonds-informatie.asp?naam=Aegon&cat=koersen&subcat=1&instrumentcode=955000020");//url here
//load HTML into DOM object
//ref http://www.php.net/manual/en/domdocument.loadhtml.php
//note html does not have to be well fpr,ed with this function

$dom_object = new DOMDocument();
@$dom_object->loadHTML($html_string);

//perform Xpath queries on DOM
//ref http://www.php.net/manual/en/domxpath.query.php

$xpath = new DOMXPath($dom_object);

//perform Xpath query
//use any specfic property to narrow focus

$nodes = $xpath->query("//table[@class='maintable']/tbody/tr[4]/td[2]/table[@class='koersen_tabel']/tbody/tr[2]/td[@class='koersen_tabel_midden']");

//setup some basic variables

$i = -1; //$i = counter

//when process nodes as below, cycling trough
//but not grabbing data from the header row of the table

$result = array();

//preform xpath subqueries to get numbers

foreach($nodes as $node){
    $i++;
    //using each 'node' as the limit for the new xpath to search within
    //make queries relative by starting them with a dot (e.g. ".//...")

    $details = $xpath->query("//table[3]/tbody/tr/td[1]/table[@class='fonds_info_koersen_links']/tbody/tr[1]/td[2]", $node);
    foreach($details as $detail){
        $result[$i][''] = $detail->nodeValue;
    }

    $details = $xpath->query("//table[3]/tbody/tr/td[1]/table[@class='fonds_info_koersen_links']/tbody/tr[4]/td[2]", $node);
    foreach($details as $detail){
         $result[$i][''] = $detail->nodeValue;
    }

    if(curl_errno($rawhtml)){
        echo 'Curl error: ' . curl_error($rawhtml);

        print'<pre>';   
        print_r($result);
        print '</pre>';
    }
}

?>

我已经通过Chrome的元素检查器检查了xpath查询，它们似乎是正确的。我真的不知道代码有什么问题。

Answer 1

这行代码怎么样？

$result[$i][''] = $detail->nodeValue;

不应该看起来像这样：

$result[$i][] = $detail->nodeValue;

（看方括号）

Answer 2

我已经重写了我的抓取工具并使用了PHP Simple HTML DOM Parser。这解决了我的问题，现在一切正常：）。

Scraper返回空数组

2 个答案: