C#'s null coalescing operator (??) in PHP
Is there a ternary operator or the like in PHP that acts like ?? of C#?
?? in C# is clean and shorter, but in PHP you have to do something like:
// This is absolutely okay except that $_REQUEST['test'] is kind of redundant.
echo isset($_REQUEST['test'])? $_REQUEST['test'] : 'hi';
// This is perfect! Shorter and cleaner, but only in this situation.
echo null? : 'replacement if empty';
// This line gives error when $_REQUEST['test'] is NOT set.
echo $_REQUEST['test']?: 'hi';
PHP 7 adds the null coalesce operator:
// Fetches the value of $_GET['user'] and returns 'nobody'
// if it does not exist.
$username = $_GET['user'] ?? 'nobody';
// This is equivalent to:
$username = isset($_GET['user']) ? $_GET['user'] : 'nobody';
You could also look at short way of writing php's ternary operator ?: (php >=5.3 only)
// Example usage for: Short Ternary Operator
$action = $_POST['action'] ?: 'default';
// The above is identical to
$action = $_POST['action'] ? $_POST['action'] : 'default';
And your comparison to C# is not fair. "in PHP you have to do something like" - In C# you will also have a runtime error if you try to access a non-existent array/dictionary item.
The Null Coalesce Operator, ( ?? ) has been accepted and implemented in PHP 7. It differs from the short ternary operator ( ?: ) in that ?? will suppress the E_NOTICE that would otherwise occur when attempting to access an array where it doesn't have a key. The first example in the RFC gives:
$username = $_GET['user'] ?? 'nobody';
// equivalent to: $username = isset($_GET['user']) ? $_GET['user'] : 'nobody';
Notice that the ?? operator does not require the manual application of isset to prevent the E_NOTICE .
I use function. Obviously it is not operator, but seems cleaner than your approach:
function isset_or(&$check, $alternate = NULL)
{
return (isset($check)) ? $check : $alternate;
}
Usage:
isset_or($_REQUEST['test'],'hi');
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