如何使用PHP开发简单的表单生成器功能

class FormBuilder {
    private $fields;

    public function __construct() {
        $this->fields = [];
    }

    public function addField($type, $name, $label) {
        $field = [
            'type'  => $type,
            'name'  => $name,
            'label' => $label
        ];

        $this->fields[] = $field;
    }

    public function generateForm() {
        $form = '<form>';

        foreach ($this->fields as $field) {
            $form .= '<div>';
            $form .= '<label>' . $field['label'] . '</label>';

            switch ($field['type']) {
                case 'text':
                    $form .= '<input type="text" name="' . $field['name'] . '">';
                    break;
                case 'email':
                    $form .= '<input type="email" name="' . $field['name'] . '">';
                    break;
                case 'password':
                    $form .= '<input type="password" name="' . $field['name'] . '">';
                    break;
                // 其他类型字段的处理...
            }

            $form .= '</div>';
        }

        $form .= '</form>';

        return $form;
    }
}

// 创建表单生成器实例
$formBuilder = new FormBuilder();

// 添加文本输入框字段
$formBuilder->addField('text', 'username', '用户名');
$formBuilder->addField('password', 'password', '密码');

// 生成表单HTML代码
$form = $formBuilder->generateForm();

// 输出表单
echo $form;