Object-Oriented JavaScript

Pre-defined Functions

There are a number of functions that are built into the JavaScript engine and available for you to use. Let's take a look at them. While doing so, you'll have a chance to experiment with functions, their parameters and return values , and become comfortable in working with them. The list of the built-in functions is:

• parseInt()
• parseFloat()
• isNaN()
• isFinite()
• encodeURI()
• decodeURI()
• encodeURIComponent()
• decodeURIComponent()
• eval()

Tip

The Black Box Function

Often, when you invoke functions, your program doesn't need to know how these functions work internally. You can think of a function as a black box: you give it some values (as input parameters) and then you take the output result it returns. This is true for any function—one ...