uasort

Synopsis

Returns

TRUE on success; FALSE on failure

Description

uasort() sorts array by the value of each element, using the specified user-defined function named by func . Key/value relationships are preserved. This function is useful if the values of an associative array must be in some specific non-regular order, such as when you want to do a non-case-sensitive sort with both uppercase and lowercase alphabets.

func should be written to accept two parameters, which it must compare with each other. If they're considered equivalent, 0 should be returned. If the first is considered to be greater, 1 should be returned. If the second is considered to be greater, -1 should be returned.

Version

PHP 3 since 3.0.4, PHP 4

See also

See also array_multisort() , arsort() , asort() , krsort() , ksort() , natsort() , natcasesort() , rsort() , sort() , uksort() , usort()

Example

function uasort_cmp($a, $b) { // Sort in ascending order
   if (strtolower($a) == strtolower($b)) return 0;
   return (strtolower($a) > strtolower($b)) ? 1 : -1;
}

$arr = array("tom" => "Apple", "janet" => "apple",
             "fred" => "Banana", "barney" => "banana",
             "bullwinkle "=> "Carrot", "rocky" => "carrot");
uasort($arr, "uasort_cmp");
while(list($k, $v) = each($arr)) {
   echo "$k => $v\n";
}

Output:
tom => Apple
janet => apple
fred => Banana
barney => banana
bullwinkle => Carrot
rocky => carrot