Unset,array in PHP

It's very simple to delete an array element in PHP, but sometimes deleting an array requires some sort of index. We'll use the relevant function, and here we'll introduce the difference between using Unset,array_splice to remove elements from an array.

If you want to delete an element in an array, you can use the unset directly, but the index of the array does not rearrange:

　　

$arr = Array (' A ', ' B ', ' C ', ' d ');

Unset ($arr [1]);

Print_r ($arr);

?>

The result:

Array ([0] => a [2] => C [3] => D)

So how do you get the missing elements to be filled and the array will be indexed? The answer is Array_splice ():

　　

$arr = Array (' A ', ' B ', ' C ', ' d ');

Array_splice ($arr, 1, 1);

Print_r ($arr);

?>

The result:

Array ([0] => a [1] => C [2] => D)

Remove a specific element from an array

　　

$arr 2 = Array (1, 3, 5,7,8);

foreach ($arr 2 as $key => $value)

{

if ($value = = 3)

unset ($arr 2[$key]);

}

Var_dump ($arr 2);

?>

Supplemental Delete Empty Array

Instance:

　　

$array = (' A ' => ' abc ', ' B ' => ' BCD ', ' C ' => ' CDE ', ' d ' => ' def ', ' e ' => ');

Array_filter ($array);

echo "

";

Print_r ($array);
?>
Results:
Array (
[A] => ABC
[b] => BCD
[C] => CDE
[d] => def
)
Summarize
If the Array_splice () function is deleted, the index value of the array also changes.
If the unset () function is deleted, the index value of the array does not change.