php delete specified array

PHP is a widely used server-side scripting language commonly used to develop web applications. In PHP, array is a very common data type that can be used to store large amounts of data, such as text, numbers, and objects. However, sometimes, we need to remove specific elements from the array. This article will introduce how to delete specified elements in a PHP array.

Use the unset() function to delete specified array elements

PHP has a built-in function called unset(), which can be used to delete specified variables. In PHP, an array element is actually just a variable, so we can use the unset() function to delete a specific array element.

Here is a simple example showing how to delete elements from a PHP array:

<?php

$fruits = array('apple', 'banana', 'cherry', 'dates', 'elderberry');

// 删除第2个元素
unset($fruits[1]);

// 打印数组
print_r($fruits);

?>

In this example, we have created an array called $fruits that contains 5 elements . We used the unset() function to delete the 2nd element (i.e. "banana"). Finally, we printed the array using the print_r() function so we can view the results.

You can run this example in the console or browser to see its output. You will find that the second element in the array has been deleted, and the printed result only contains 4 elements (ie "apple", "cherry", "dates" and "elderberry").

Use the array_diff() function to delete multiple specified elements

If you want to delete multiple specified array elements, you can use the PHP built-in function array_diff(). This function finds the difference between two arrays, i.e. returns only the elements that are present in the first array.

Here is a simple example showing how to use the array_diff() function to delete multiple elements in a PHP array:

<?php

$fruits = array('apple', 'banana', 'cherry', 'dates', 'elderberry');

// 要删除的元素
$to_remove = array('banana', 'dates');

// 使用array_diff()函数删除指定元素
$fruits = array_diff($fruits, $to_remove);

// 打印数组
print_r($fruits);

?>

In this example, we first create an object called $fruits An array containing 5 elements. We then create another array, $to_remove, which contains the elements we want to remove (i.e. "banana" and "dates"). Finally, we use the array_diff() function to remove these elements and assign the result to the $fruits array. Finally, we print the result using the print_r() function again so we can see the elements in the array.

You can run this example in the console or browser to see its output. You will find that the "banana" and "dates" elements in the array have been deleted, and only 3 elements (i.e. "apple", "cherry" and "elderberry") are left in the printed result.

Use the array_splice() function to delete the specified element and keep the array key value

If you want to delete the specified element in the array and keep the key values ​​of other elements unchanged, you need to use array_splice ()function.

Here is a simple example that shows how to use the array_splice() function to delete specified elements in a PHP array and keep the key value:

<?php

$fruits = array('a' => 'apple', 'b' => 'banana', 'c' => 'cherry', 'd' => 'dates', 'e' => 'elderberry');

// 删除b，c两个元素
$removed = array_splice($fruits, 1, 2);

// 打印原数组和删除的元素
print_r($fruits);
print_r($removed);

?>

In this example, we create an array named $fruits array, which contains 5 elements, each element has a key name. We used the array_splice() function to delete the two elements with keys "b" and "c". This function returns a new array containing the deleted elements (i.e. "banana" and "cherry"). Finally, we use the print_r() function to print the array and the deleted elements.

You can run this example in the console or browser to see its output. You will find that the two specified elements in the array have been deleted, and only 3 elements (ie "a", "d" and "e") are left in the printed result. At the same time, we can see that the deleted elements are returned in a new array.

Conclusion

In PHP, various methods can be used to delete specified array elements. You can use the unset() function to delete one element, the array_diff() function to delete multiple elements, or the array_splice() function to delete a specified element and keep the keys of other elements unchanged. You can choose a method that suits you based on your specific needs to delete specified elements from the array.

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