######HTML Writing comments in HTML, XHTML, and XML. Simply surround the text you want commented out with
<!-- YOUR TEXT HERE -->
If you want to stop your JavaScript from executing when placed in a HTML_file add // before the end -->
<!-- YOUR SCRIPT HERE //-->
######CSS In CSS, it's a little different, using C code style comments.
/* YOUR TEXT HERE */
Same goes for multi-line comments.
/* This is
a multi-line
comment */
######JavaScript Single Line Comments in a Javascript file start with //
Any text between // and the end of a line, will be will not be executed
The example below is a single line comment in front of each line, to explain the code.
// Change heading:
document.getElementById("myH").innerHTML = "My First Page";
// Change paragraph:
document.getElementById("myP").innerHTML = "My first paragraph.";
Javascript comments can also be placed at the end of the line of code.
var x = 7; // Declare x, give it the value of 7
Using comments to prevent execution of code can be awesome for testing.
Adding // in front of a code line changes the code lines from an executable line to a comment.
The below example uses // to prevent execution of a single line of code.
var x = 5; // Declare x, give it the value of 5
You can also stop multiple lines from exciting by using /* at the start and */ at the end.
/*
document.getElementById("myH").innerHTML = "My First Page";
document.getElementById("myP").innerHTML = "My first paragraph.";
*/