正则提取的问题

Question

&nbsp; &bull;&nbsp;<a id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl02_lnkCategory" class="SearchResultsSubLevelCategory" itemprop="significantLink" href="../../Drivers/_/N-7zi3j/"><h2 class='seoh2'>驱动器</h2></a>
<span id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl02_lblstarting">(</span><span id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl02_lblRecordCount">4,449</span><span id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl02_lblclosing">)</span>
<br />&nbsp; &bull;&nbsp;<a id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl03_lnkCategory" class="SearchResultsSubLevelCategory" itemprop="significantLink" href="../../Fiber-Optic-Communications/_/N-6qrgd/"><h2 class='seoh2'>光纤通信</h2></a>
<span id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl03_lblstarting">(</span><span id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl03_lblRecordCount">6,512</span><span id="ctl00_ContentMain_uc4_listLeftCategories_ctl01_listSubCategories_ctl03_lblclosing">)</span>
<br />preg_match_all("/<a id=\"(.*?)\" class=\"SearchResultsSubLevelCategory\" itemprop=\"significantLink\" href=\"(.*?)\"><h2 class=\"seoh2\">(.*?)<\/h2><\/a>/is",$info,$arr);我想提取href=""的内容。以及<h2 class='seoh2'> 里面内容</h2></a>这里<2>标签里面内容。怎么没效果。

Answer 1

preg_match_all("/<a id=\"(.*?)\" class=\"SearchResultsSubLevelCategory\" itemprop=\"significantLink\" href=\"(.*?)\"><h2 class='seoh2'>(.*?)<\/h2><\/a>/is",$info,$arr);  h2 的class 是单引号