正则表达式和大小写

Question

i'm using this

preg_match('/<meta\s+http-equiv="Content-Type" content="([^;]+)(?:;\s*charset=["]?([^"^\s]*))?"/i', $html, $match)

to get the charset but this will not work with this

<META http-equiv=Content-Type content="text/html; charset=windows-1256">

any ideas?

Answer 1

You have double quotes in preg_match() but not in html example.

Here: http-equiv=Content-Type

If You want to support preg_match() to work with and without quotes here, simple change code to this:

preg_match('/<meta\s+http-equiv=(")?Content-Type(")?\s+content="([^;]+)(?:;\s*charset=["]?([^"^\s]*))?"/i', $html, $match);

Better version that will work when attributes order change:

preg_match('/<meta.+?content="([^;]+)(?:;\s*charset=["]?([^"^\s]*))?"/i', $html, $match);

Answer 2

If you are only interested in getting the charset, why not using something simpler like:

preg_match('/charset=([^"]+)/i', $html, $match);

Of course, you can tweak it to meet your specific needs, but keep it simple and it'll be much easier to get it to work.