Developing Interactive Sites with JavaScript

Functions are first-class members of the Javascript language and this means that they can be used in ways which are not possible in other programming languages. In this 8-video course, learners explore the use of functions as arguments to other functions, as return values of functions, and also how functions can be linked with specific objects when invoked. Key concepts covered in this course include how to assign a function to a variable and pass a function as an argument to another function; how to define and invoke a function which returns a nested function; and learning what data types in Javascript are passed by value and what types are passed by reference. Learn how to create a function from a string using the new keyword; how to use function callbacks to ensure the sequential execution of functions; and how to use the call, apply, and bind methods in order to link a function call to a specific object.

Explore different features available in Javascript to manipulate elements of a web page by using its Document Object Model (DOM) structure and how Javascript interacts with a browser by using the Browser Object Model (BOM). In this 13-video course, key concepts covered include how to use the document object to retrieve individual elements of a web page and access their values and properties; how to alter web page contents by modifying a DOM; and how to retrieve children of elements of a web page as an array. Begin by observing how to write a function to generate an animation; how to define event listeners and handlers for clicks on web page buttons; and how to create handlers for events of users by clicking on buttons. Next, learners observe how to use handlers for mouse events on web page elements; how to use the screen, window, and navigator objects of BOM to get information about the end-user's environment; and how to use the window object to interact with the end-user's browser.

Form validation is a common use case for Javascript. Learners will explore basic steps involved in this process, including an overview of asynchronous programming and the use of promises to handle such code, in this 10-video course. Key concepts covered here include how to define simple registration forms with text, numerical input fields, radio buttons, check boxes and drop-down menu; how to access individual form elements and their data contents from Javascript; and learning when variables are destroyed by Javascript when a form submission navigates users to a different web page. Begin by observing a variety of form validations for different input fields; learning operations which run asynchronously in your Javascript application; and learning how to use promises to chain the execution of two functions where one depends on the results returned by the other. Next, learn a function making multiple asynchronous function calls by using async/await syntax. Finally, observe how to use the fetch function to asynchronously retrieve an image file and relate it to the XMLHttpRequest of AJAX.

HTML5, CSS3 and JavaScript provide advanced features for creating highly interactive and responsive web pages. Discover how to use JavaScript to create timers and marquees, access and validate form data, and manipulate forms with CSS3.