Get value of variable when isset() is used in PHP ternary shorthand operator

Question

In using the shorter ternary operator:

$foo = isset($_GET['bar']) ?: 'hello';

If $_GET['bar'] is set, is it possible for $foo to return the value of $_GET['bar'] instead of true ?

Edit: I understand the old school ternary works eg,

$foo = isset($_GET['bar']) ? $_GET['bar'] : 'hello';

but I want to use the newschool ternary which is the even shorter version

Answer 1

It sounds like you are asking about the new (as of PHP 7) null coalesce operator . You can do something like:

$foo = $_GET['bar'] ?? 'hello';
echo $foo;

Which if $_GET['bar'] is null will set $foo to hello .

The first operand from left to right that exists and is not NULL. NULL if no values are defined and not NULL. Available as of PHP 7.

Functional demo: https://3v4l.org/0CfbE

$foo = $_GET['bar'] ?? 'hello';
echo $foo . "\n";
$_GET['bar'] = 'good bye';
$foo = $_GET['bar'] ?? 'hello';
echo $foo;

Output:

hello
good bye

Additional reading on it: http://www.lornajane.net/posts/2015/new-in-php-7-null-coalesce-operator

Answer 2

是的，你会这样做

$foo = isset($_GET['bar']) ? $_GET['bar'] : 'hello';

Answer 3

像这样的东西：

$foo = isset($_GET['bar']) ? $_GET['bar'] : 'hello';

Answer 4

I'm not sure I understand your question, but is it something like:

$foo = isset($_GET['bar']) ? true : 'hello';

This will give you one(true) if that variable is set or just hello if it's not.

Answer 5

The answer is no (in PHP5 at least, see chris's answer for PHP7 only). For this reason I tend to use a helper function eg

function isset_or(&$variable, $default = NULL)
{
    return isset($variable) ? $variable : $default;
}

$foo = isset_or($_GET['bar'], 'hello');