What function can be used in PHP to sort an array alphabetically without regard to case?

When sorting an array alphabetically in PHP, the `sort()` function can be used. However, this function is case-sensitive, meaning that uppercase letters will be sorted before lowercase letters. To sort an array alphabetically without regard to case, the `natcasesort()` function can be used instead. This function will sort the array in a natural order, ignoring case differences.

// Sample array
$fruits = array("Apple", "banana", "Orange", "cherry");

// Sort the array alphabetically without regard to case
natcasesort($fruits);

// Output the sorted array
print_r($fruits);