獲取alt屬性的正則表達式

Question

是否有任何正則表達式來獲取alt屬性？ 例如：<img src="http://static.adzerk.net/Advertisers/a61df59863ed44e59446d0b9bb805c56.jpg" title="" alt="blahblah" border="0" height="90" width="728">

我想從圖片標籤上面得到「blahblah」。

Answer 1

Don't use regexes for parsing HTML

未經測試Demo

$string = '<img src="http://static.adzerk.net/Advertisers/a61df59863ed44e59446d0b9bb805c56.jpg" title="" alt="blahblah" border="0" height="90" width="728">'; 
$dom = new DOMDocument(); 
@$dom->loadHTML($string); 
$anchor = $dom->getElementsByTagName('img')->item(0); 
echo $anchor->getAttribute('alt');