How to delete array elements and reindex in PHP

In PHP, you can first use unset() to delete elements from the array, and then use the array_values() function to automatically numerically index the array; or use the array_splice() function to delete elements in the array, and it will automatically index. The following article will give you a detailed introduction to the method of deleting array elements and re-indexing in PHP. I hope it will be helpful to you.

First of all, let’s take a look at the PHP functions needed to delete array elements and re-index.

1. unset()

unset() is often used. It is used to destroy specified variables.

Note: unset() is not actually a real function, it is a language structure; it cannot be called by function variables and has no return value. If you try to obtain its return value, an exception will occur.

Syntax:

void unset(mixed $var [, mixed $... ] )

2. array_values() function

array_values() function will return all the values ​​in the array and index the array numerically (starting from 0 and increments by 1).

Syntax:

array array_values(array $array)

3. array_splice() function

array_splice() function can delete the specified element from the array and replace it with a new element; then returns a new array.

Sentence pattern:

array_splice(array,start,length [, array... ])

Below we introduce the method of deleting array elements and re-indexing in PHP through simple code examples.

Example 1:

<?php  
header("content-type:text/html;charset=utf-8"); 
$arr1 = array( 
  
    &#39;php中文网&#39;, // [0] 
    &#39;网址：&#39;, // [1] 
    &#39;m.sbmmt.com&#39; // [2] 
  
); 
  
// 删除索引1处的“网址：”项
unset($arr1[1]);  
  
// 输出修改后的数组
var_dump($arr1); 
  
// 重新索引数组元素
$arr2 = array_values($arr1); 
  
// 输出重新索引的数组
var_dump($arr2); 

?>

Rendering:

<?php  
header("content-type:text/html;charset=utf-8"); 
$arr1 = array( 
  
    &#39;php中文网&#39;, // [0] 
    &#39;网址：&#39;, // [1] 
    &#39;m.sbmmt.com&#39; // [2] 
  
); 
// 输出数组
var_dump($arr1); 
echo "<br>";
// 删除索引1处的“网址：”项
array_splice($arr1, 1, 1);    
// 输出修改后的数组
var_dump($arr1); 
  

?>

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