PHP array removal null value Array_filter () method

Function name: Array_filter ()
Call mode: Array_filter ($array)
Parameter description: $array is the object of operation, we will delete the empty element

Instance:

The code is as follows	Copy Code
<?php $array = (' A ' => ' abc ', ' B ' => ' BCD ', ' C ' => ' CDE ', ' d ' => ' def ', ' e ' => '); Array_filter ($array); echo "<pre>"; Print_r ($array); ?> Results: Array ( [A] => ABC [b] => BCD [C] => CDE [d] => def )

foreach or while, using these two syntactic constructs to delete the empty elements in the array, the simple code is as follows:

The code is as follows	Copy Code
<?php foreach ($arr as $k =&gt; $v) { if (! $v) Unset ($arr [$k]); } >

And I feel very good, but this is not high efficiency has been tried, first $arr into objects, and then take advantage of the characteristics of the object to delete, because: foreach is the current operation of the array into

Line copy, each operation of foreach, is a copy of a variable, the page if there are too many foreach, will be a very large consumption.