How can the PHP class for generating HTML code be structured to ensure flexibility in customizing the editor's appearance?

To ensure flexibility in customizing the editor's appearance using a PHP class for generating HTML code, we can structure the class with methods for setting different attributes such as font size, color, alignment, etc. This allows users to easily customize the appearance of the editor by calling these methods with their desired settings.

class HTMLEditor {
    protected $content;

    public function __construct($content) {
        $this->content = $content;
    }

    public function setContent($content) {
        $this->content = $content;
    }

    public function setFontSize($size) {
        return "<span style='font-size: $size;'>$this->content</span>";
    }

    public function setFontColor($color) {
        return "<span style='color: $color;'>$this->content</span>";
    }

    public function setAlignment($alignment) {
        return "<div style='text-align: $alignment;'>$this->content</div>";
    }
}

// Example usage
$editor = new HTMLEditor("Hello, world!");
echo $editor->setFontSize("20px");
echo $editor->setFontColor("red");
echo $editor->setAlignment("center");