Wrap single line paragraphs in string

Make a headline from single lines

[PetNov]

Hi,
I have text (string) like this:

Blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah.

Blah blah blah blah

Blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah.

So, we have 3 paragraphs, made by returns and newlines (could be html <p> tags, doesnt matter, we can convert it anyway). Now, every single-line paragraph we want to wrap with <h2> and </h2> tags - make a heading from it.

How could this be done? Me - no idea.

Thank you for help.

[httpwebwitch]

split the text into an array with one line in each element.
loop through it.
if the length of the string is shorter than X (the length at which a "wrap" might occur),
$str .= "<h2>".$line."</h2>";
else,
$str .= "<p>".$line."</p>";

echo $str and you're done.

[PetNov]

Thanks, great!