What This Book Covers

We'll begin by looking at exactly what JavaScript is and then take our first steps with the underlying language and syntax. You'll learn all the fundamental programming concepts, including data and data types, and structuring your code to make decisions in your programs or to loop over the same piece of code many times.

Once you're comfortable with the basics, we'll move on to one of the key ideas of JavaScript—the object. You'll learn how to take advantage of the objects that are native to the JavaScript language, such as Dates and Strings, and find out how these objects allow you to manage complex data and simplify your programs. Next, you'll see how we can use JavaScript to manipulate objects made available to us in the browser, such as forms, windows, and other controls. Using this knowledge, we can start to create truly professional-looking applications that allow us to interact with the user.

Long pieces of code are very hard to get right every time—even for the experienced programmer—and JavaScript code is no exception. We look at common syntax and logical errors, how we can spot them, and how to use the Microsoft Script Debugger to aid us with this task. Also, we need to examine how we handle the errors that slip through the net, and ensure that these do not detract from the experience of the end user of our application.

From here, we'll move on to more advanced topics, such as using cookies, jazzing up our web pages with Dynamic HTML, and introducing XML. Finally, we'll move away from manipulation of data and code on the client-side and discuss ASP, the environment that enables dynamic generation of web content using server-side scripting and back-end databases.

The appendices at the end of the book provide you with a comprehensive reference for the JavaScript language. They also include solutions to the exercises found at the end of each chapter.

All the new concepts that are introduced in this book are illustrated with practical examples, which allow you to experiment with JavaScript and build on the theory that you have just learned. Throughout the book, we'll also be building up a more complex sample application—an online trivia quiz—which will allow you to see how JavaScript is used in action in a real-world situation.