Help with Regex

There is some tags with missing quote.

<img src=file.jpg border="0" alt=text goes here title=this is a title />

replace to:

<img src="file.jpg" border="0" alt="text goes here" title="this is a title" />

How can that be done?

 

$str = preg_replace('`([a-z])=([^"]*?)\s+(?=[a-z]+=|/)`', '\1="\2" ', $str);

Code (markup):

Note that it's a fragile regex due to the fundamentally ambiguous nature of your inputs. Things like slashes and equal signs in the attribute values can mess it up.