要使用PHP的is_array()函數檢查一個變量是否為數組，只需將該變量作為參數傳遞給函數
<?php
$variable1 = array("apple", "banana", "cherry");
$variable2 = "This is a string";
if (is_array($variable1)) {
echo "Variable 1 is an array.";
} else {
echo "Variable 1 is not an array.";
}
if (is_array($variable2)) {
echo "Variable 2 is an array.";
} else {
echo "Variable 2 is not an array.";
}
?>
在這個例子中，$variable1是一個數組，所以輸出結果是"Variable 1 is an array.“。而$variable2是一個字符串，所以輸出結果是"Variable 2 is not an array.”。
