


PHP: Detailed explanation of usage differences of unset and array_splice with examples
Deleting array elements in php is very simple, but sometimes deleting an array requires some sorting of the index. We will use the relevant functions , here we will introduce the difference between using unset,array_spliceDelete elements in an array
If you want to delete an element in an array, you can directly Use unset, 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 the missing elements be filled and the array re-indexed? Woolen cloth? 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 specific elements in the array<?php
$arr2 = array(1,3, 5,7,8);
foreach ($arr2 as $key=>$value){
if ($value === 3)
unset($arr2[$key]);
}
var_dump($arr2);
?>
Supplementary deletion of empty array
Example:<?php
$array = ('a' => "abc", 'b' => "bcd",'c' =>"cde",'d' =>"def",'e'=>"");
array_filter($array);
echo "<pre class="brush:php;toolbar:false">";
print_r($array);
?>
Array (
[a] => abc
[b] => bcd
## [c] => cde[d] => def
)
Summary
If the array_splice() function is deleted, the index value of the array will also change.
If the unset() function is deleted, the index value of the array will not change.
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