RegEx不支持预测！

Question

Hey guys, I am trying to match "address" in this page -

http://www.bbb.org/norfolk/business-reviews/tax-return-preparation/liberty-tax-service-in-virginia-beach-va-48000604

The source of address part has this HTML

<tr>
    <td align="right" class="generalinfo_left">Address:</td>
    <td class="generalinfo_right">1 S Main St Ste 1430<br /></td>
</tr>
<tr>
    <td align="right" class="generalinfo_left"></td>
    <td class="generalinfo_right">Dayton, OH 45402</td>
</tr>

So, I tried the following RegEx in PHP.

"%Address:</td>(.*?)(?!<br />)</td>%s"

where "s" is the modifier for "." to match new lines too. But it is not working. It doesnt matches the "Dayton, OH 45402" part. Can anyone tell me why?

Answer 1

It's pretty normal: If you look at your sample text, you will see that between Address and Dayton, OH 45402, you have <br />. (?!<br />) specifically states that it should not match if <br /> is found.

You should use parser for HTML.

That said, assuming that all your files are exactly like this sample, this ugly regex should work:

%(Address:)(.*?generalinfo_right">)(.*?)((<br />)|(</td>))(.*?generalinfo_right">)(.*?)((<br />)|(</td>))%s

Groups 1, 3 and 8 contain the address.

However, since most likely your documents are not all exactly like that, a much better solution will be to parse HTML with a proper parser.