Creating basic PHP programs and scripts begins with basic output. There are two commands to accomplish this in PHP: echo and print. In both cases, if you are creating a web page, the output should be a web page that will validate at the W3C validator. This means one should include the HTML DocType and other required tags as shown in the example below.
Example: Simple PHP Output with Hyperlink
Example: Simple PHP Output with Hyperlink
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>PHP Example</title>
</head>
<body>
<?php
echo "<p>Welcome</p>";
echo "<p>This is an example</p>";
echo "<p><a href=\"http://www.google.com/\">Google</a></p>";
echo '<p><a href="http://www.google.com/">Google</a></p>';
?>
</body>
</html>
Example: Single vs. Double Quotes
There is a difference between the use of double quotes versus single quotes in an echo statement. Single quotes will not print the output of a variable or function as evident in the example below.
<?php
$y = 5 * 2;
echo "<p>$y</p>";
echo '<p>$y</p>';
?>
Example: The Importance of HTML Tags
The importance of including HTML tags in the echo or print can be seen in this next example. The output of this program is:
55
Versus 5 on one line and 5 on the next line.
<?php
$x = 2;
$y = 3;
echo $x + $y;
print $x + $y;
?>
</code>
Example: echo vs. print
The PHP print and echo commands only differ in that print is a function and thus has a return value and thus can be used in expressions. Echo can take multiple parameters and can be faster. The example below demonstrates these differences as well as the use of a PHP comment/remark.
<?php
echo "<p>Hello. ", "How are you today?</p>"
// next line would produce an error so it's commented out
// print "<p>Hello.", "How are you today?</p>"
$a ? print "true" : print "false"; // print used in an expression
print "<p>$a</p>";
?>
Example: Multi-line Echo
<?php
echo "<ul>
<li>Apples
<li>Oranges
<li>Grapes
</ul>";
?>