PHP supports 'C', 'C++' and Unix shell-style (Perl style) comments. For example:
The "one-line" comment styles only comment to the end of
the line or the current block of PHP code, whichever comes first.
This means that HTML code after // ... ?>
or # ... ?> WILL be printed:
?> breaks out of PHP mode and returns to HTML mode, and
// or # cannot influence that.
If the asp_tags configuration directive
is enabled, it behaves the same with // %> and
# %>.
However, the </script> tag doesn't break out of PHP mode in
a one-line comment.
'C' style comments end at the first */ encountered.
Make sure you don't nest 'C' style comments. It is easy to make this
mistake if you are trying to comment out a large block of code.
