Is using a nested set structure a recommended approach for representing questionnaires with conditional logic in PHP?
Using a nested set structure can be a recommended approach for representing questionnaires with conditional logic in PHP as it allows for efficient querying of nested data and handling of conditional logic. By structuring the questionnaire data in a nested set model, you can easily traverse the hierarchy of questions and apply conditional logic based on the user's responses.
// Example of implementing nested set structure for questionnaire with conditional logic in PHP
// Define a class for representing the questionnaire node
class QuestionnaireNode {
public $id;
public $parent_id;
public $left;
public $right;
public $question;
public $conditional_logic;
public function __construct($id, $parent_id, $left, $right, $question, $conditional_logic) {
$this->id = $id;
$this->parent_id = $parent_id;
$this->left = $left;
$this->right = $right;
$this->question = $question;
$this->conditional_logic = $conditional_logic;
}
}
// Create an array of questionnaire nodes representing the nested set structure
$questionnaire = [
new QuestionnaireNode(1, null, 1, 12, 'Question 1', null),
new QuestionnaireNode(2, 1, 2, 3, 'Question 2', 'if answer to Question 1 is Yes'),
new QuestionnaireNode(3, 1, 4, 11, 'Question 3', 'if answer to Question 1 is No'),
new QuestionnaireNode(4, 3, 5, 6, 'Question 4', null),
new QuestionnaireNode(5, 4, 7, 8, 'Question 5', 'if answer to Question 4 is Yes'),
new QuestionnaireNode(6, 4, 9, 10, 'Question 6', 'if answer to Question 4 is No'),
];
// Traverse the nested set structure and apply conditional logic based on user responses
foreach ($questionnaire as $node) {
if ($node->conditional_logic) {
// Check the user's response to the question referenced in the conditional logic
// Apply the conditional logic based on the response
// For example, show or hide the question based on the response
}
}