isset PHP isset($_GET['something']) ? $_GET['something'] : ''

Question

I am looking to expand on my PHP knowledge, and I came across something I am not sure what it is or how to even search for it. I am looking at php.net isset code, and I see isset($_GET['something']) ? $_GET['something'] : ''

I understand normal isset operations, such as if(isset($_GET['something']){ If something is exists, then it is set and we will do something } but I don't understand the ?, repeating the get again, the : or the ''. Can someone help break this down for me or at least point me in the right direction?

Solution 1

It's commonly referred to as 'shorthand' or the Ternary Operator.

$test = isset($_GET['something']) ? $_GET['something'] : '';

means

if(isset($_GET['something'])) {
    $test = $_GET['something'];
} else {
    $test = '';
}

To break it down:

$test = ... // assign variable
isset(...) // test
? ... // if test is true, do ... (equivalent to if)
: ... // otherwise... (equivalent to else)

Or...

// test --v
if(isset(...)) { // if test is true, do ... (equivalent to ?)
    $test = // assign variable
} else { // otherwise... (equivalent to :)

Solution 2

In PHP 7 you can write it even shorter:

$age = $_GET['age'] ?? 27;

This means that the $age variable will be set to the age parameter if it is provided in the URL, or it will default to 27.

See all new features of PHP 7.

Solution 3

That's called a ternary operator and it's mainly used in place of an if-else statement.

In the example you gave it can be used to retrieve a value from an array given isset returns true

isset($_GET['something']) ? $_GET['something'] : ''

is equivalent to

if (isset($_GET['something'])) {
 echo "Your error message!";
} else {
 $test = $_GET['something'];
}

echo $test;

Of course it's not much use unless you assign it to something, and possibly even assign a default value for a user submitted value.

$username = isset($_GET['username']) ? $_GET['username'] : 'anonymous'

Solution 4

You have encountered the ternary operator. It's purpose is that of a basic if-else statement. The following pieces of code do the same thing.

Ternary:

$something = isset($_GET['something']) ? $_GET['something'] : "failed";

If-else:

if (isset($_GET['something'])) {
    $something = $_GET['something'];
} else {
    $something = "failed";
}

Solution 5

It is called the ternary operator. It is shorthand for an if-else block. See here for an example http://www.php.net/manual/en/language.operators.comparison.php#language.operators.comparison.ternary

View more solutions

Comments

[Bright umor]

This isn't really plain.