Set php array to empty

In PHP, an array can store multiple elements. But in some cases we may need to make an array empty. This article will introduce how to set an array to be empty in PHP.

In PHP, we can use the following method to empty the array:

1. Use the unset() function

The unset() function can delete the array When we use unset() to delete all elements of an element in the array, the array will be empty. The following is a sample code:

//定义数组
$array = array(1, 2, 3, 4, 5);

//使用unset()函数删除元素
foreach($array as $key => $value){
    unset($array[$key]);
}

//输出数组
print_r($array);

The output result is an empty array:

Array
(
)

It should be noted that the unset() function will only delete the values ​​and keys in the array, and the structure of the array itself Nothing will change.

2. Using the array() function

In PHP, you can use the array() function to create an empty array. An example is as follows:

//创建空数组
$array = array();

//输出数组
print_r($array);

The output result is an empty array:

Array
(
)

It should be noted that the array created using this method will not retain any elements, including previously existing elements.

3. Using assignment statements

We can use assignment statements to set an existing array to an empty array. An example is as follows:

//定义数组
$array = array(1, 2, 3, 4, 5);

//将数组置空
$array = array();

//输出数组
print_r($array);

The output result is an empty array:

Array
(
)

It should be noted that in this case, the original array will be completely overwritten. If other variables previously referenced the array, they will also be affected because the array reference has been changed.

To sum up, we can use the unset() function, array() function or assignment statement to empty a PHP array. Depending on the specific situation, we can choose different methods. Either way, be careful to consider array references and side effects.

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