User Interfaces: How Do I Input and Output Data?

JavaScript is the language of the web. So, it’s no wonder that inputting and outputting data is almost entirely about interacting with the web page on which your JavaScript program is running. In this chapter, we’ll discuss how to make your program interact with the web page in which it’s embedded, specifically how to read data from the user through forms and graphical user interface controls, and how to manipulate elements of the web page using the Document Object Model (DOM). In addition to discussing examples, you will also develop a small application yourself (with solution) as an exercise.