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How to determine if an array is empty in php
- PHPzOriginal
- 2023-04-19 11:37:591317browse
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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