How to determine if an array is empty in php

In PHP, to determine whether an array is empty, you can use the following method.

Method 1: Use the empty() function

The empty() function can detect whether a variable is empty. If the variable is undefined, null, false, 0 or an empty string, it will return true. Therefore, you can use the empty() function to detect whether an array is empty.

Sample code:

$arr = array();

if (empty($arr)) {
    echo '数组为空';
} else {
    echo '数组不为空';
}

Output result:

数组为空

Method 2: Use the count() function

The count() function can return the elements in an array number, if the array is empty, 0 is returned. Therefore, you can use the count() function to determine whether the array is empty.

Sample code:

$arr = array();

if (count($arr) == 0) {
    echo '数组为空';
} else {
    echo '数组不为空';
}

Output result:

数组为空

Method 3: Use isset() function

isset() function can detect whether a variable has been defined and not null. If a variable is undefined or null, the isset() function returns false. Therefore, you can use the isset() function to detect whether the array is empty.

Sample code:

$arr = array();

if (!isset($arr[0])) {
    echo '数组为空';
} else {
    echo '数组不为空';
}

Output result:

数组为空

In summary, the above three methods can be used to determine whether an array is empty. The most commonly used method is to use empty() function.

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