How to clear subscripts and values ​​​​in an array in php

PHP is a widely used open source server-side scripting language, which is designed as a tool for quickly writing Web programs. In PHP, arrays are a common data type that are often used to store large amounts of data. The subscripts and values ​​in the array can help us better process and manage data, but sometimes we also need to clear the subscripts and values ​​in the array.

This article will introduce how to use PHP to clear subscripts and values ​​​​in arrays, including using unset() function, array_values() function and array_filter() function and other methods to help you better process and manage Array data.

Use the unset() function to delete elements in the array

PHP provides the unset() function, which can delete specified elements in the array, including the subscript and value of the element. For example, the following code can delete the element with the subscript "apple" in the array $fruit:

$fruit = array("apple"=>"red", "banana"=>"yellow", "orange"=>"orange");
unset($fruit["apple"]);

In the above code, the unset() function is used to delete the element with the subscript "apple" in the array $fruit. . You can view the result by printing the $fruit array:

print_r($fruit);

The output result is:

Array ( [banana] => yellow [orange] => orange )

You can see that the element with the subscript "apple" in the array $fruit has been successfully deleted .

Use the array_values() function to re-index the array

After using the unset() function to delete an array element, the subscripts of other elements will not change, so you can use the array_values() function to re-index the array. For example, the following code can delete the element with the index "apple" in the array $fruit and re-index the array using the array_values() function:

$fruit = array("apple"=>"red", "banana"=>"yellow", "orange"=>"orange");
unset($fruit["apple"]);
$fruit = array_values($fruit);

In the above code, the element with the index "apple" in the array $fruit is deleted elements of "apple" and reindexed the array using the array_values() function. You can view the result by printing the $fruit array:

print_r($fruit);

The output result is:

Array ( [0] => yellow [1] => orange )

It can be seen that the array $fruit is re-indexed successfully, and the subscripts are arranged starting from 0.

Use the array_filter() function to filter array elements

Another method is to use the array_filter() function to filter array elements. The array_filter() function is an array filter function in PHP. It can filter array elements according to the provided callback function to generate a new array.

For example, the following code can use the array_filter() function to filter the elements in the array $fruit and delete elements with a value of "yellow":

$fruit = array("apple"=>"red", "banana"=>"yellow", "orange"=>"orange");
$fruit = array_filter($fruit, function($value) {
    return $value != "yellow";
});

In the above code, use the array_filter() function The elements in the array $fruit are filtered, elements with the value "yellow" are removed, and a new array is returned. You can view the result by printing the $fruit array:

print_r($fruit);

The output result is:

Array ( [apple] => red [orange] => orange )

You can see that the element with the value "yellow" in the array $fruit has been successfully deleted.

Summary

In PHP, there are many ways to clear the subscripts and values ​​​​in an array, such as using the unset() function to delete elements, using the array_values() function to re-index the array, and Use the array_filter() function to filter elements and other methods. Which method to choose depends on the specific needs and situations. I hope this article can help you better process and manage PHP array data.

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