Module 6: Advanced JavaScript Features
38 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary purpose of a PHP script in the context of AJAX?

  • To execute JavaScript code
  • To style web pages
  • To process requests and interact with the database (correct)
  • To display HTML content on the client-side

    • The Fetch API is used to make HTTP requests in a similar manner as XMLHttpRequest.

    True

    Name one example of a library that is used for data visualization.

    Chart.js

    The jQuery library is commonly used for ______ in web development.

    <p>DOM manipulation</p> Signup and view all the answers

    Match the following libraries with their primary functionality:

    <p>jQuery = DOM manipulation axios = HTTP requests React = UI creation Chart.js = Data visualization</p> Signup and view all the answers

    What is a key difference between libraries and frameworks?

    <p>You can plug code into a framework, but must plug frameworks into your code.</p> Signup and view all the answers

    All frameworks support both front-end and back-end development.

    <p>False</p> Signup and view all the answers

    Name one example of a CSS framework.

    <p>Bootstrap</p> Signup and view all the answers

    A framework provides a ______ for how the developer's code should be structured.

    <p>template</p> Signup and view all the answers

    Match the following programming languages with their corresponding back-end frameworks:

    <p>PHP = Laravel Java = Spring Python = Django Ruby = Ruby on Rails</p> Signup and view all the answers

    What is an important step to take when uploading files through PHP?

    <p>Check the file type being uploaded</p> Signup and view all the answers

    The $_SESSION superglobal array is used to store data that can be accessed across different user sessions.

    <p>False</p> Signup and view all the answers

    What is the purpose of using the enctype attribute in a file upload form?

    <p>To specify how the form data should be encoded when submitted.</p> Signup and view all the answers

    In PHP, session variables store data into a temporary file that is destroyed once the ________ is closed.

    <p>website</p> Signup and view all the answers

    Match the following PHP terms with their descriptions:

    <p>enctype = Specifies encoding type for form submission $_SESSION = Array storing session data file upload = Transferring files from client to server sql injection = A type of security vulnerability in queries</p> Signup and view all the answers

    Which of the following statements about functions in JavaScript is true?

    <p>Functions in JavaScript are first-class objects.</p> Signup and view all the answers

    A Promise in JavaScript is used to handle synchronous tasks.

    <p>False</p> Signup and view all the answers

    What method is used to handle a fulfilled or resolved promise in JavaScript?

    <p>.then()</p> Signup and view all the answers

    The syntax used to convert an object to a JSON string is ______.

    <p>JSON.stringify</p> Signup and view all the answers

    In JavaScript, anonymous functions can be expressed as:

    <p>Arrow functions.</p> Signup and view all the answers

    Functions in JavaScript can only be named and cannot be anonymous.

    <p>False</p> Signup and view all the answers

    What is the purpose of the resolve and reject arguments in a Promise?

    <p>To handle the completion or failure of an asynchronous task.</p> Signup and view all the answers

    What is the purpose of AJAX?

    <p>To enable data exchange without reloading the webpage</p> Signup and view all the answers

    The XMLHttpRequest object is a newer innovation than the Fetch API.

    <p>False</p> Signup and view all the answers

    What does the fetch() method return?

    <p>A Promise</p> Signup and view all the answers

    AJAX stands for Asynchronous JavaScript and ______.

    <p>XML</p> Signup and view all the answers

    What must occur to start a session for a user logging in?

    <p>User credentials must match those stored in a database</p> Signup and view all the answers

    Which method is used to initiate the request in XMLHttpRequest?

    <p>open()</p> Signup and view all the answers

    Match the AJAX features with their definitions:

    <p>asynchronous = Processes occur without interrupting user actions Promise object = Represents the completion of an asynchronous operation XMLHttpRequest = The original way to implement AJAX requests Fetch API = A modern method for making AJAX calls</p> Signup and view all the answers

    Session variables can only be used after calling session_start().

    <p>True</p> Signup and view all the answers

    What should be encoded if a user's login credentials do not match the database?

    <p>an error message</p> Signup and view all the answers

    The send() function can be called with an empty argument when using POST requests.

    <p>False</p> Signup and view all the answers

    Sessions are stored on the ______, while cookies are saved on the user's ______.

    <p>server-side, browser</p> Signup and view all the answers

    Name one method that can be used to extract the message body from a Response object after a fetch() call.

    <p>text() / json() / blob() / formData() / arrayBuffer()</p> Signup and view all the answers

    Match the session-related terms with their descriptions:

    <p>session_start() = Initiates or resumes a session session variables = Store user-specific data during a session logout.php = Script to destroy a user session HTTP cookies = Used for tracking or identifying returning users</p> Signup and view all the answers

    Which statement about using prepared statements in login forms is true?

    <p>They prevent SQL injection attacks.</p> Signup and view all the answers

    Cookies can be used to store data for general client-side purposes.

    <p>True</p> Signup and view all the answers

    What happens to a session when a user logs out?

    <p>the session is destroyed</p> Signup and view all the answers

    Study Notes

    Module 6: Additional Scripting Features

    • This module covers advanced JavaScript scripting, including first-class functions, asynchronous features, and object manipulation.

    Objectives

    • Discuss how functions are first-class objects in JavaScript.
    • Utilize functions as well as other relevant Javascript features (Promise, fetch, etc.) in web applications.
    • Apply techniques for asynchronous JavaScript and XML (AJAX).

    Functions in JS

    • Functions are first-class objects in JavaScript, allowing flexibility in coding.
    • Functions can be stored in variables.
    • Functions can be part of arrays.
    • Functions can be passed as arguments to other functions.
    • Functions can serve as the return value of a function.
    • Functions can be defined as expressions and assigned to variables.
    • Functions can be named or anonymous.
    • Anonymous functions can be expressed as arrow functions.

    User-defined Objects

    • JavaScript uses new Object() to create objects.
    • Objects are collections of properties and methods.
    • Properties store data, and methods are functions contained within the object.
    • Accessing properties: person.name or person['name'].
    • Object literals: var subject = {};
    • Object literals allow defining properties directly within the object.
    • Object constructors: function Student (idno, name, course, year)
      • Use the new keyword to create objects.
      • this keyword refers to the current object.
      • prototype.toString creates a method accessible on all object instances.

    JSON

    • JavaScript Object Notation (JSON) is a text syntax for storing and exchanging data among applications.
    • JavaScript allows converting JSON-formatted strings to objects, and vice-versa.
      • JSON.stringify(objecttype) converts a JavaScript object to a JSON string.
      • JSON.parse(stringtype) converts a JSON string to a JavaScript object.

    Promise

    • A Promise represents the eventual completion or failure of an asynchronous task (e.g. network request).
    • A promise contains a value which is made available to the user at a later time.
    • Promises are instantiated with a function that takes resolve and reject as arguments.
      • resolve is called when the operation succeeds.
      • reject is called when the operation fails.
      • .then() is used to handle a fulfilled (successful) promise.
      • .catch() is used to handle a rejected (failed) promise.

    AJAX

    • Asynchronous JavaScript and XML (AJAX) is a set of techniques that allow for interactions with a server without requiring a full page reload.
    • AJAX techniques typically use XMLHttpRequest or the Fetch API to make requests to a server and get updated or new data sent to the client-side.

    AJAX & PHP

    • Use Javascript's XMLHttpRequest or Fetch API to send asynchronous requests to a PHP script on the server.
    • The PHP script processes the request and returns a response back to the client (JavaScript).

    Libraries

    • A collection of utilities and functions.
    • Can be for specific needs.
    • Functions/modules in a library can be reused, which may save time.
      • Examples: jQuery, jQuery UI, React, Validator, Pristine, Chartist.js, and more.

    Frameworks

    • A framework provides a structure or template for building applications.
    • Developers plug their specific code into the framework.
    • Front-end frameworks use JavaScript and/or CSS to handle the client part of the application.
      • Examples: Angular, Vue.js, Ember.js, Semantic UI, Next.js
    • Back-end frameworks handle server logic, often using specific server-side languages.
      • Examples: Laravel, Symfony, CodeIgniter, Yii, Zend (PHP); Spring, Struts, Grails, DropWizard (Java); Express, DerbyJS, Koa, Meteor (Node.js); Django, Pyramid, Flask (Python); Ruby on Rails (Ruby)

    Handling File Uploads with PHP

    • Enable file uploads in your PHP configuration.
    • Use a form with enctype="multipart/form-data" to handle file uploads.
    • Retrieve the uploaded file data using $_FILES.
    • Ensure correct error handling for upload failures.
    • Manage file naming to avoid conflicts.
    • Move the uploaded file securely to a designated directory.

    Session Handling with PHP

    • Session handling in PHP allows you to manage user data across multiple requests within a single browser session.
    • Store data in the $_SESSION array to maintain state between requests.
    • The session starts with session_start();.
    • The session_unset() function clears all session variables for a specific user.
    • session_destroy() deletes the session.

    Cookies in PHP

    • Cookies in PHP are used to store data on the client's machine (browser).
    • Cookies provide a way to maintain information about a user across multiple visits to a website. -Use session_start().

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Module 6: Additional Scripting Features PDF

    Description

    This quiz focuses on advanced JavaScript concepts, including first-class functions, asynchronous programming, and object manipulation. Explore how these features enhance web applications and their practical applications. Test your understanding of concepts like Promises and AJAX in JavaScript.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser