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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
<h1>JavaScript Comments</h1>
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<p class="intro">JavaScript comments can be used to make the code more readable.</p>
<hr />
<h2>JavaScript Comments</h2>
<p>Comments can be added to explain the JavaScript, or to make it more readable.
</p>
<p>Single line comments start with //.</p>
<p>This example uses single line comments to explain the code:</p>
<table width="100%" border="1" class="ex" cellspacing="0" id="table2">
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<pre><script type="text/javascript">
// This will write a header:
document.write("<h1>This is a header</h1>");
// This will write two paragraphs:
document.write("<p>This is a paragraph</p>");
document.write("<p>This is another paragraph</p>");
</script></pre>
</td></tr>
</table>
<p><a target="_blank" href="tryit.asp@filename=tryjs_comments1">Try it yourself.</a></p>
<hr />
<h2>JavaScript Multi-Line Comments</h2>
<p>Multi line comments start with /* and end with */.</p>
<p>This example uses a multi line comment to explain the code:</p>
<table width="100%" border="1" class="ex" cellspacing="0" id="table3">
<tr><td>
<pre><script type="text/javascript">
/*
The code below will write
one header and two paragraphs
*/
document.write("<h1>This is a header</h1>");
document.write("<p>This is a paragraph</p>");
document.write("<p>This is another paragraph</p>");
</script></pre>
</td></tr>
</table>
<p><a target="_blank" href="tryit.asp@filename=tryjs_comments2">Try it yourself.</a></p>
<hr />
<h2>Using Comments to Prevent Execution</h2>
<p>In this example the comment is used to prevent the execution of a single code line:</p>
<table width="100%" border="1" class="ex" cellspacing="0" id="table4">
<tr><td>
<pre><script type="text/javascript">
document.write("<h1>This is a header</h1>");
document.write("<p>This is a paragraph</p>");
//document.write("<p>This is another paragraph</p>");
</script></pre>
</td></tr>
</table>
<p><a target="_blank" href="tryit.asp@filename=tryjs_comments3">Try it yourself.</a></p>
<p>In this example the comments is used to prevent the execution of multiple code lines:</p>
<table width="100%" border="1" class="ex" cellspacing="0" id="table5">
<tr><td>
<pre><script type="text/javascript">
/*
document.write("<h1>This is a header</h1>");
document.write("<p>This is a paragraph</p>");
document.write("<p>This is another paragraph</p>");
*/
</script></pre>
</td></tr>
</table>
<p><a target="_blank" href="tryit.asp@filename=tryjs_comments4">Try it yourself.</a> </p>
<hr />
<h2>Using Comments at the End of a Line</h2>
<p>In this example the comment is placed at the end of a line:</p>
<table width="100%" border="1" class="ex" cellspacing="0" id="table6">
<tr><td>
<pre><script type="text/javascript">
document.write("Hello"); // This will write "Hello"
document.write("Dolly"); // This will write "Dolly"
</script></pre>
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
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