How can I only get the alt attribute of the a p tag in PHP?

问题

I'm working on a script that echo's only the price. If I do:

$alttag = $oNode['p'];
echo $alttag;

It will echo everything in . So it will echo:

roodmerk of cafeïnevrij pak 500 gram

2 pakken

prijs per kilo 1,99

199

from the website, so you can see it echo´s 199, that´s the price but first I ONLY need 199 in the  and I want . or , between 199 so it will show 1,99 or 1.99.

If I do:

$alttag = $oNode['p sup'];
echo $alttag;

It will only echo 99 out of  If I do:

$alttag = $oNode['p sup'];
$maintag = $oNode['p']->attr('alt');
echo $maintag . $alttag;

Well... This does nothing How can I only get the 1 and 99 and place a . or , between it so it will look like 1,99 or 1.99?

 <div class="item-prijs">
        <p>
            <cufon class="cufon cufon-canvas" alt="1" style="width: 27px; height: 42px; ">
                <canvas width="47" height="43" style="width: 47px; height: 43px; top: -1px; left: -2px; "></canvas>
                <cufontext>1</cufontext>
            </cufon>
            <sup>
                <cufon class="cufon cufon-canvas" alt="99" style="width: 24px; height: 20px; ">
                    <canvas width="35" height="21" style="width: 35px; height: 21px; top: -1px; left: -1px; ">
                    </canvas><cufontext>99</cufontext>
                </cufon>
            </sup>
        </p>
    </div>

Complete code: without the includes php functions and datbase connection.

// Extracts offers from html and return in array
function extractSparOffers($url)
{
    loadPqUrl($url);
    //Test $dates  = extractDateRange(pq('.contentdatagrid td:first'));
    $oNodes = pq('.item');
    if($oNodes->count() == 0) throw new Exception('No offers were found.');

    foreach($oNodes as $oNode) {

        $oNode = pq($oNode);
        //Test $titleDescCell = $oNode['input#a']->parent();
        //Test $titleDescCell['img, input']->remove();
        $priceCell = $oNode['span.price1']->parent()->parent();

        // Get title and description
        $data['title']                          = $oNode['.item-content h3'];
        $data['description']                    = $oNode['.item-content p'];
        // Get prices (page may contain price ranges)


        $alttag = $oNode['p sup'];
        $maintag = $oNode['p']->attr('alt');
        echo $maintag;

        //echo $alttag;

        //$alttags=preg_match_all('/<img[^>]*alt="([^"]*)"/i', $html, $matches);
        $none = "0.00";
        $data['priceBefore']                    = $none;
        $data['priceAfter']                     = $alttag;
        //                                        $oNode['item-prijs p.sup.cufon cufon-canvas']->attr('alt') ;
        // Get image  
        $imgNode = $oNode['img:only-child'];
        if(count($imgNode) > 0)
            $img = getimg('http://www.spar.nl/' . $oNode['img:only-child']->
                          attr('src'));
        else $img = '';                                     
        $data['image']                          = $img;

    //Test  $data['dateStart']                      = $dates['start'];
    //Test  $data['dateEnd']                        = $dates['end'];
    $date                    =date('Y-m-d');
    $data['dateStart']  = date('Y-m-d',  strtotime("yesterday"));
    $data['dateEnd']                    = date('Y-m-d', strtotime("tomorrow"));
        $data = formatOfferStrings($data);

        $odTotal[] = $data;
    }

    return $odTotal;
}

spiderInit();
$offerData = extractSparOffers('http://www.spar.nl/aanbiedingen/');
//Test processNewOffers('Spar', $offerData, $offerData[0]['dateStart']);
processNewOffers('Spar', $offerData, $dates['start']);


?>

回答1:

So is this basically a web crawler for prices? I would suggest you look into using PHP's DOMDocument library to parse XML (Which XHTML practically is). You could then do something like:

//create a new DOMDocument object
$xmlDoc = new DOMDocument();  
//load your html for parsing
$xmlDoc->loadHTML("<html><body>Your HTML Code<br></body></html>");
//select the element that you want the attribute from...you may need to use $xmlDoc->getElementsByTagName('p');
$p_element = $xmlDoc->getElementById('yourtag');
//get the attribute alt of the selected element
$alt = $p_element->getAttribute('alt');
//show alt attribute value
echo $alt;

This is just pseudo code and will not solve your problem, however it seems to be a better solution than the parser you are trying to use. Look at these links for more information (I hope this helps):

http://www.php.net/manual/en/domdocument.construct.php

http://php.net/manual/en/domelement.getattribute.php

http://www.php.net/manual/en/domdocument.getelementsbytagname.php

http://www.php.net/manual/en/domdocument.getelementbyid.php

来源：https://stackoverflow.com/questions/8256189/how-can-i-only-get-the-alt-attribute-of-the-a-p-tag-in-php

标签

php

parsing