XPATH DomDocument检索div元素的第一个节点

Question

Here is my HTML:

<div class="content">
    <div class="post">
        <img class="img" src="getme"/> (<~~ retrieve this one)
        <img class="img" src="notme"/>
        <img class="img" src="notme"/>
    </div>
    <div class="post">
        <img class="img" src="getme"/> (<~~ retrieve this one)
        <img class="img" src="notme"/>
        <img class="img" src="notme"/>
    </div>      
</div>

Here is the XPATH's I've used:

     //div[@class="content"]//div[@class="post"]//@src[1]
     (//div[@class="content"]//div[@class="post"]//@src)[1]

What I'm trying to accomplish is retrieving only the ones I explicitly stated as to retrieve. When I use the second Xpath ( (//div[@class="content"]//div[@class="post"]//@src)[1] ) one it only provides the first img src and thats it (not the first one for every div post element)

Answer 1

Use the following xpath query:

//div[@class="post"]/img[1]/@src

Example:

$html = <<<EOF
<div class="content">
    <div class="post">
        <img class="img" src="getme"/> (<~~ retrieve this one)
        <img class="img" src="notme"/>
        <img class="img" src="notme"/>
    </div>
    <div class="post">
        <img class="img" src="getme"/> (<~~ retrieve this one)
        <img class="img" src="notme"/>
        <img class="img" src="notme"/>
    </div>    
</div>
EOF;

$doc = new DOMDocument();
@$doc->loadHTML($html);

$selector = new DOMXPath($doc);

foreach($selector->query('//div[@class="post"]/img[1]/@src') as $node) {
    var_dump($node->nodeValue);
}

Output:

string(5) "getme"
string(5) "getme"