Question

IEnumerable<char> sequence = "abc".Concat("def");
foreach (var element in sequence)
{
   Console.WriteLine(element); // Prints a, then b, then c, then d, then e, then f
}

输出

sequence

regex *仅返回preg_match_all中的最后一个匹配匹配已发生但尚未返回到输出数组如何获取所有URL？

当我尝试使用两个preg_match_all获取

内容然后匹配所有图片但我想只使用一个

时，它有效

Answer 1

您可以使用DOMDocument：

$html = "<p class='images'>
<img src='URL1'>
<img src='URL2'>
<img src='URL3'>
<img src='URL4'>

</p>

<p><img src='ThisNot'></p>
";

$dom = new DOMDocument;
$dom->loadHTML($html);
$tags = $dom->getElementsByTagName('p');
$urls = array();
foreach($tags as $p){
    if($p->getAttribute('class') == "images"){
        $imgs = $p->getElementsByTagName('img');
        foreach($imgs as $img){
            $urls[] = $img->getAttribute('src');
        }
    }
}
print_r($urls);

<强>输出：

Array
(
    [0] => URL1
    [1] => URL2
    [2] => URL3
    [3] => URL4
)

preg_match_all循环匹配

1 个答案: