Quick Tip: Echo() Function for PHP

Oct 25th/2010

Comments and suggestions in here

Today we like to recommend something nice for programmers, echo() is not function properly but a language construct, so you won’t need to use parentheses with it; echo() does not present a function behavior, which means that it cannot always be used in a function’s context. If you want to pass more than one parameter to echo(), the parameters must not be contained within parentheses. This short syntax only works with the short_open_tag configuration setting enabled.

Here’s an example of how echo() works:

<?php
echo "Hello World";

echo "This spans
multiple lines. The newlines will be
output as well";

echo "This spansnmultiple lines. The newlines will benoutput as well.";

echo "Escaping characters is done "Like this".";

// You can use variables inside of an echo statement
$foo = "foobar";
$bar = "barbaz";

echo "foo is $foo"; // foo is foobar

// You can also use arrays
$baz = array("value" => "foo");

echo "this is {$baz['value']} !"; // this is foo !

// Using single quotes will print the variable name, not the value
echo 'foo is $foo'; // foo is $foo

// If you are not using any other characters, you can just echo variables
echo $foo;          // foobar
echo $foo,$bar;     // foobarbarbaz

// Some people prefer passing multiple parameters to echo over concatenation.
echo 'This ', 'string ', 'was ', 'made ', 'with multiple parameters.', chr(10);
echo 'This ' . 'string ' . 'was ' . 'made ' . 'with concatenation.' . "n";

echo <<<END
This uses the "here document" syntax to output
multiple lines with $variable interpolation. Note
that the here document terminator must appear on a
line with just a semicolon. no extra whitespace!
END;

// Because echo does not behave like a function, the following code is invalid.
($some_var) ? echo 'true' : echo 'false';

// However, the following examples will work:
($some_var) ? print 'true' : print 'false'; // print is also a construct, but
// it behaves like a function, so
// it may be used in this context.
echo $some_var ? 'true': 'false'; // changing the statement around
?>