JavaScript and JQuery: Interactive Front-End Web Development

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FUNCTIONS, METHODS & OBJECTS

Browsers require very detailed instructions about what we want them to do. Therefore, complex scripts can run to hundreds (even thousands) of lines. Programmers use functions, methods, and objects to organize their code. This chapter is divided into three sections that introduce:

FUNCTIONS & METHODS

Functions consist of a series of statements that have been grouped together because they perform a specific task. A method is the same as a function, except methods are created inside (and are part of) an object.

OBJECTS

In Chapter 1 you saw that programmers use objects to create models of the world using data, and that objects are made up of properties and methods. In this section, you learn how to create your own objects using JavaScript.

BUILT-IN OBJECTS

The browser comes with a set of objects that act like a toolkit for creating interactive web pages. This section introduces you to a number of built-in objects, which you will then see used throughout the rest of the book.

WHAT IS A FUNCTION?

Functions let you group a series of statements together to perform a specific task. If different parts of a script repeat the same task, you can reuse the function (rather than repeating the same set of statements).

Grouping together the statements that are required to answer a question or perform a task helps organize your code.

Furthermore, the statements in a ...