How to delete multiple elements from an array using PHP

In PHP, sometimes you need to delete multiple elements from an array. This may confuse some PHP beginners because they don't know how to manipulate arrays. In this article, we will discuss how to delete multiple elements from an array using PHP.

First method: Use the unset() function to delete elements

In PHP, we can use the unset() function to delete elements in the array. The syntax of this function is as follows:

unset($array[key1], $array[key2], ..., $array[keyn]);

Among them, $array is the array to be operated on, key1, key2,..., keyn are the key names of the elements to be deleted.

The following is a sample code:

$array = array('apple', 'banana', 'cherry', 'durian');
unset($array[1], $array[3]);
print_r($array);

The output result is:

Array
(
    [0] => apple
    [2] => cherry
)

Here, we use the unset() function to delete the second element in the array (i.e.' banana') and the fourth element (i.e. 'durian'), and the deleted array is output.

It should be noted that when using the unset() function to delete array elements, the key names are not consecutive. Therefore, we need to use the print_r() function to observe the key names in the array when outputting the array.

Second method: Use the array_splice() function to delete elements

Another way to delete array elements is to use the array_splice() function. The syntax of this function is as follows:

array_splice($array, $offset, $length, $replacement);

Among them, $array is the array to be operated on, $offset is the position of the element to be deleted, $length is the number of elements to be deleted, and $replacement is the element to be inserted (can be select).

The following is a sample code:

$array = array('apple', 'banana', 'cherry', 'durian');
array_splice($array, 1, 2);
print_r($array);

The output result is:

Array
(
    [0] => apple
    [2] => durian
)

Here, we use the array_splice() function to delete the second element in the array (i.e. ' banana') and the third element (i.e. 'cherry'), and the deleted array is output. It should be noted that when using this function to delete elements, the key names will be consecutive.

Third method: Use the array_diff() function to delete elements

In addition to using the unset() function and array_splice() function, you can also use the array_diff() function to delete array elements. The syntax of this function is as follows:

array_diff($array, $values);

where $array is the array to be operated on, and $values ​​is the array of values ​​of the elements to be deleted.

The following is a sample code:

$array = array('apple', 'banana', 'cherry', 'durian');
$values = array('banana', 'durian');
$array = array_diff($array, $values);
print_r($array);

The output result is:

Array
(
    [0] => apple
    [1] => cherry
)

Here, we put the value of the element to be deleted in an array $values, and then use The array_diff() function deletes it from the array $array and outputs the deleted array.

It should be noted that when using the array_diff() function to delete elements, the key names will remain intact.

Conclusion

The above three methods can be used to delete multiple elements in the PHP array. When using these methods, you need to choose the most suitable method based on actual needs. For example, when deleting consecutive elements in an array, it is best to use the array_splice() function; when deleting discontinuous elements in an array, it is best to use the unset() function or array_diff() function.

No matter which method we choose, we should pay attention to the continuity of the array key names and the consistency of the array values. Only in this way can we get the correct results and maintain the integrity of the array.

The above is the detailed content of How to delete multiple elements from an array using PHP. For more information, please follow other related articles on the PHP Chinese website!