我正在尝试找到最简单的方法，使用 PHP 获取指定元素/类中第一个图像的 URL，插入到 Open Graph og:image 和 Twitter twitter:image
<figure class="pictures">
<img src="/pictures/1.jpg"> <!-- it would be this here -->
<img src="/pictures/2.jpg">
<img src="/pictures/3.jpg">
</figure>
<meta property="og:image" content="<?php echo $og_image; ?>"/>
还想知道我是否可以让它通过回显获取相对 URL 前面的域，而不是在元标记中的回显前面硬编码它。
试试这个：
function gsb($string, $start, $end)
{
$string = " " . $string;
$ini = strpos($string, $start);
if ($ini == 0)
return "";
$ini += strlen($start);
$len = strpos($string, $end, $ini) - $ini;
return substr($string, $ini, $len);
}
$pic=gsb($string,'src="','"');
我没有安装PHP，所以我实际上无法测试这段代码。但把它当作表达这个想法的伪代码。
<?php
echo "<figure class='pictures'>";
$URLS = array("/pictures/1.jpg","/pictures/2.jpg","/pictures/3.jpg");
for($i=0;$i<count($URLS);i++) {
echo "<img src='$URLS($i)'>";
}
echo "</figure>";
echo "<meta property='og:image' content='$URLS(0)' />";
?>
这将为您提供所需的结果，使添加/删除 img 更容易，并且如果您的代码朝该方向构建，则允许您通过算法生成 img 列表。
要获取服务器的域，请结帐$_SERVER['HTTP_HOST']并$_SERVER['SERVER_NAME']
with javascript like this BUT
**by using php FOLLOW THIS LINK**
[http://stackoverflow.com/questions/10130858/get-img-src-with-php][1]
//this is jquery code for finding the SRC of first imahe
<script>
//$( document ).ready(function() {//here we are playing with image so use
$( window ).load(function() {
var image_url = $( ".pictures img:first-child" ).attr("src");
//in variable image_url the url of the image
alert(image_url);
});
</script>
[1]: http://stackoverflow.com/questions/10130858/get-img-src-with-php
USING PHP:-
<?php
//i just copy that code from upper link and make small change
//if you are generating these image by loop then generate $html variable and use this code
$html = '<img src="/arrow_down.png"><img src="/arrow_down1.png"><img src="/arrow_down2.png">';
$doc = new DOMDocument();
$doc->loadHTML($html);
$xpath = new DOMXPath($doc);
echo $src = $xpath->evaluate("string(//img/@src)"); # "/images/image.jpg"
?>