What are the best practices for handling form data in PHP to avoid undefined errors?

When handling form data in PHP, it is crucial to check if the form fields are set before trying to access their values to avoid undefined errors. One common practice is to use the isset() function to check if the form field exists in the $_POST or $_GET superglobals before using it in your code. 

if(isset($_POST['field_name'])){
    $field_value = $_POST['field_name'];
    // Process the form data
}

Keywords

validation sanitization isset empty error handling

Related Questions