Section 4.8. Comments

4.8. Comments

While in PHP mode, you can mark certain parts of your code as a comment that should not be executed. There are three ways of doing this: //, /* */, and #. // and # mean "Ignore the rest of this line," whereas /* means "Ignore everything until you see */." Some complications exist with /* and */ that make them less desirable to use.

     <?php             print "This is printed\n";             // print "This is not printed\n";             # print "This is not printed\n";             print "This is printed\n";             /* print "This is not printed\n";             print "This is not printed\n"; */     ?>

That chunk of code shows all three types of comments in action, but does not demonstrate the problem with the /* */ form of commenting. If you were to start a /* comment on line one, and end it on the line near the bottom where the other /* comment is started, you would find that the script would fail to work. The reason for this is that you cannot stack up, or "nest," /* */ comments, and attempting to do so will fail spectacularly.

It is generally best to stick to // for your commenting purposes, simply because it is easy to spot, easy to read, and easy to control.