How does the use of isset() and empty() functions differ in PHP when checking for empty variables in a form submission?

When checking for empty variables in a form submission, the isset() function checks if a variable is set and not null, while the empty() function checks if a variable is empty (e.g., null, empty string, 0, or false). It's common to use isset() to ensure a variable exists before checking if it's empty using empty(). This approach helps to avoid errors when accessing non-existent variables. 

if(isset($_POST['submit'])){
    $name = isset($_POST['name']) ? $_POST['name'] : '';
    
    if(!empty($name)){
        // Process the form data
    } else {
        echo "Name field is empty";
    }
}

Keywords

isset empty functions PHP form submission

Related Questions