How to clear string array elements in php

In PHP, sometimes we need to clear all elements in a string array in order to reuse the array. At this time, you can use PHP's built-in array operation function. The specific implementation method is as follows.

Methods to clear string arrays

Method 1: Use the unset keyword

The unset keyword can be used to delete specified array elements. Therefore, we can iterate through the entire array and use unset each time to delete elements in the array to clear the array.

Sample code:

<?php 
$strings = array("hello", "world", "you", "are", "amazing");

for ($i = 0; $i < count($strings); $i++) {
    unset($strings[$i]);
}

print_r($strings);
?>

Output result:

Array()

Method 2: Use the array_splice function

array_splice function can delete the specified element in the array and return An array containing the deleted elements.

Sample code:

<?php
$strings = array("hello", "world", "you", "are", "amazing");

array_splice($strings, 0, count($strings));

print_r($strings);
?>

Output result:

Array()

Method 3: Use array_filter function

array_filter function can filter the elements in the array and return a A new array containing unfiltered elements. If the callback function is not specified, array_filter will remove elements with a value of FALSE.

Sample code:

<?php
$strings = array("hello", "world", "you", "are", "amazing");

$strings = array_filter($strings);

print_r($strings);
?>

Output result:

Array()

Notes

When using the unset keyword and array_splice function, you need to pay attention to whether the subscript of the array is continuous. If the subscripts of the array are not consecutive, some unexpected problems may occur.

When using the array_filter function, you need to pay attention to the return value of the callback function. If there is a problem with the return value of the callback function, it may also cause some unexpected problems.

Conclusion

Among the above three methods, it is recommended to use the array_filter function to clear the array, because this method is relatively simple and easy to understand, and it can also ensure the continuity of the array subscript. However, if the array has consecutive subscripts, using the unset keyword and the array_splice function is also a viable option.

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