How to remove an element from an array in php

In PHP, operating arrays is one of the frequently occurring requirements. When we need to remove an element from an array, PHP provides several different methods. In this article, we will discuss these methods to help readers find their favorite method.

Method 1: unset() function

The unset() function is one of the most basic methods to remove specified elements from an array. It takes two parameters, the first parameter is an array and the second parameter is the key of the element to be deleted, for example:

$birds = array('crow', 'pigeon', 'sparrow');
unset($birds[1]);

In this example, we create an array with three elements$ birds. Then, we used the unset() function to delete the element "pigeon" with index 1 (i.e. the second). Now, the $birds array contains only two elements: 'crow' and 'sparrow'.

Method 2: array_splice() function

The array_splice() function can be used to delete or replace one or more elements from an array. It takes three arguments: the first is the array to be modified, the second is the index of the first element to be removed or replaced, and the third is the number of elements to be removed or replaced. If we only want to delete one element, then the number should be 1. For example:

$birds = array('crow', 'pigeon', 'sparrow');
array_splice($birds, 1, 1);

In this example, we used the array_splice() function to remove the second element from the $birds array. The first parameter is the array to be modified, and the second parameter is the position where the deletion starts, here it is index 1. The third parameter is the number of elements to remove, here it is 1. Now, the $birds array contains only two elements: 'crow' and 'sparrow'.

Method 3: array_diff() function

The array_diff() function can be used to delete specified elements from an array. It takes two parameters, the first is the array to operate on, and the second is the element to be deleted. For example:

$birds = array('crow', 'pigeon', 'sparrow');
$remove = array('pigeon');
$birds = array_diff($birds, $remove);

In this example, we first create an array $birds containing three elements, and then create an array $remove containing the element 'pigeon' to be deleted. Next, we use the array_diff() function to remove all elements contained in the $remove array from the $birds array. Now, the $birds array contains only two elements: 'crow' and 'sparrow'.

Method 4: unset() array_values() function

If we use the unset() function to delete an element, an empty element will be left in the array. In some cases we may want to not keep empty elements after removing them. To do this, we can use a combination of the unset() function and the array_values() function, for example:

$birds = array('crow', 'pigeon', 'sparrow');
unset($birds[1]);
$birds = array_values($birds);

In this example, we first use the unset() function to delete the element 'pigeon' with index 1, The array is then reindexed using the array_values() function, thus removing empty elements. Now, the $birds array contains only two elements: 'crow' and 'sparrow'.

Conclusion

The above are several different ways to remove an element from an array in PHP. Each method has its advantages and disadvantages. Readers can choose the method that suits them best and use it in their own code. Either way, we can easily solve this problem.

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