如何在PHP中按页面获取图像URL

Question

This is my code :

<form method="POST">
    <input name="link">
    <button type="submit">></button>
</form>
<title>GET IMAGE URL</title>
<?php 
if (!isset($_POST['link'])) exit();
$link = $_POST['link'];
$parse = explode('.html', $link);
echo '<div id="pin" style="float:center"><textarea class="text" cols="110" rows="50">';
for ($i = 1; $i <=5; $i++)
{
    if ($i > 1)
    $link = "$parse[0]-$i.html";
    $get = file_get_contents($link);
    if (preg_match_all('/src="(.*?)"/', $get, $matches))
    {
        foreach ($matches[1] as $content)
        echo $content."\r\n";
    }
}
echo '</textarea>';

The page I'm trying to get the img src has 10 to 15 page,so I want my code to get all the img url until the end of the page. How can I do that without the loop?

If I use:

for ($i = 1; $i <=5; $i++)

this will get only 5 page img urls, but I want to make it get until the end. Then I don't need to edit the loop everytime I submit another URL with a different number of pages.

Answer 1

From this

this will get only 5 page img urls, but I want to make it get until the end. Then I don't need to edit the loop everytime I submit another URL with a different number of pages.

I could understand that your problem is with dynamic number of pages.Your urls have a next page link at the bottom

下一页

Identify it and get your images in while loop

<?php

// Link given in form
$link = "http://www.xiumm.org/photos/XiuRen-17305.html";
$parse = explode('.html', $link);
$i=1;
// Intialize a boolean 
$nextPageFound = true;


while($nextPageFound) {
    // Construct URL Every time when nextPageFound
    if ($i == 1) {
        $url = "$parse[0].html";
        echo "First Page<br><br>";
     } else {
        $url = "$parse[0]-$i.html";
       }

    // Getting URL Contents
    $get = file_get_contents($url);
    if (preg_match_all('/src="(.*?)"/', $get, $matches))
    {
    // echoing contents
    foreach ($matches[1] as $content)
    echo $content."<br>";
    }
    // check nextPageBtn if available 
    if (strpos($get, '"nextPageBtn"') !== false) {
     $nextPageFound = true;
     // increment +1
     $i++;
    echo "<br>Page $i<br><br>";
    } else {
     $nextPageFound = false;
     echo "THE END";
    }

}
?>

Answer 2

You should use an HTML/XML parser, like DOMDocument , in combination with DOMXPath ( xpath is query language to query (X)HTML data structures):

// create DOMDocument
$doc = new DOMDocument();
// load remote HTML file
$doc->loadHTMLFile( $link );

// create DOMXPath
$xpath = new DOMXPath( $doc );
// fetch all IMG elements that have a src attribute
$nodes = $xpath->query( '//img[@src]' );

// loop trough found IMG elements and echo their src attribute values
for( $i = 0; $i < $nodes->length; $i++ ) {
  echo $nodes->item( $i )->getAttribute( 'src' ) . PHP_EOL;
}

---

Regarding the xpath query //div[contains(@class,'pic_box')]//@src , mentioned by @Enuma, in the comments:

The resulting DOMNodeList of that query will not contain DOMElement objects, but DOMAttr objects, because the query directly asks for attributes, not elements. Since DOMAttr represents an attribute and not an element, the method getAttribute() does not exist. To get the value of the attribute you have to use the property DOMAttr->value .

So, we have to slightly alter the relevant part of our example code from above to:

// loop trough found src attributes and echo their value
for( $i = 0; $i < $nodes->length; $i++ ) {
  echo $nodes->item( $i )->value . PHP_EOL;
}

Putting it all together, our example code then becomes:

// create DOMDocument
$doc = new DOMDocument();
// load remote HTML file
$doc->loadHTMLFile( $link );

// create DOMXPath
$xpath = new DOMXPath( $doc );
// fetch all src attributes that are descendants of div.pic_box 
$nodes = $xpath->query( '//div[contains(@class,'pic_box')]//@src' );

// loop trough found src attributes and echo their value
for( $i = 0; $i < $nodes->length; $i++ ) {
  echo $nodes->item( $i )->value . PHP_EOL;
}

---

^{PS.: In order for DOMDocument to be able to load remote files, I believe some php config setting may be required to be set, which I don't know off the top of my head, right now. But since it already appeared to be working for @Enuma, it's not actually relevant now. Perhaps I'll look them up later.}