#include <Array.au3>

Global $array[20]
$array[1] = "Test"
$array[3] = "Mull"
$array[4] = "Blub"
_ArrayDisplay($array)

For $i = UBound($array) - 1 To 0 Step -1
    If $array[$i] = "" Then _ArrayDelete($array, $i)
Next
_ArrayDisplay($array)