PHP Method to delete the last element of an array
When using a PHP array, sometimes you need to delete the last element. This can be achieved in different ways, and this article will describe these methods, along with their pros and cons.
Method 1: Use array_pop()
The array_pop() function is used in PHP to pop the last element of the array. The syntax of this method is as follows:
<code>mixed array_pop ( array &$array )</code>
Not only does this method remove and return the last element of the array, but it also modifies the passed array itself. Therefore, we can use it in the following way:
<code>$arr = array("apple", "banana", "orange", "grape"); $last_element = array_pop($arr); print_r($arr);</code>
Output result: Array ( [0] => apple [1] => banana [2] => orange )
We can see that the last element "grape" is removed and returned through the $last_element variable. But the $arr array has been modified, removing "grape".
Method 2: Use unset() and array_key_last()
After PHP version 7.3, the array_key_last() function was introduced, which returns the last array key. We can use this in conjunction with the unset() function to delete the last element of the array. The following is an example of using this method:
<code>$arr = array("apple", "banana", "orange", "grape"); unset($arr[array_key_last($arr)]); print_r($arr);</code>
Output result: Array ([0] => apple [1] => banana [2] => orange )
This kind The benefit of the method is that it does not return the deleted element, but deletes it directly in the original array. However, if the array is empty, the array_key_last() function will return null, which may cause an error.
Method 3: Use array_slice()
We can also use array_slice() to delete the last element. Using this method, we can copy the entire array, excluding the last element, thereby removing that element. The following is an example of using this method:
<code>$arr = array("apple", "banana", "orange", "grape"); $arr = array_slice($arr,0,-1); print_r($arr);</code>
Output result: Array ([0] => apple [1] => banana [2] => orange )
This kind The benefit of the method is that we can keep the original elements in the original array without losing data. However, this approach requires copying the entire contents in the array, which can consume a lot of memory if the array is large.
Summary
This article introduces three methods to delete the last element of a PHP array:
Although each method has its own advantages and disadvantages, you can choose according to your needs and code . At the same time, we also need to pay attention to the existence of variables when using the unset() method and array keys.
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