What common error message might occur when using the in_array() function in PHP, and how can it be resolved?

When using the in_array() function in PHP, a common error message that might occur is "Warning: in_array() expects parameter 2 to be array." This error happens when the second parameter provided to the in_array() function is not an array. To resolve this issue, ensure that the second parameter is indeed an array before using the in_array() function.

// Example code snippet to resolve the "Warning: in_array() expects parameter 2 to be array" error
$my_array = [1, 2, 3, 4, 5];
$value_to_check = 3;

if (is_array($my_array)) {
    if (in_array($value_to_check, $my_array)) {
        echo "Value found in array!";
    } else {
        echo "Value not found in array.";
    }
} else {
    echo "Second parameter is not an array.";
}