Difference between unset and array_splice in PHP deleting elements in array

If you want to delete 1 element in an array, you can use unset directly, but the index of the array will not be rearranged:

<?php 
$arr = array('a','b','c','d');
unset($arr[1]);
print_r($arr);
?>

The result is:

Array ( [0] = > a [2] = > c [3] = > d )

So how can we make sure that the missing elements are filled and the array is re-indexed? The answer is array_splice ():

<?php 
$arr = array('a','b','c','d'); 
array_splice($arr,1,1); 
print_r($arr); 
?>

The result is:

Array ( [0] = > a [1] = > c [2] = > d )

Delete a specific element from an array

<?php
$arr2 = array(1,3, 5,7,8);
foreach ($arr2 as $key=>$value)
{
  if ($value === 3)
    unset($arr2[$key]);
}
var_dump($arr2);
?> 

Supplement and delete empty arrays

Example:

<?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
)

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.