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Nota: Se está a trabalhar num computador/tablet/outro dispositivo em que não pode criar ficheiros, pode experimentar os examplos de código (a maioria) num programa de desenvolvimento online, tal como JSBin ou Thimble.
- Making decisions in your code — conditionals
- Looping code
- Functions — reusable blocks of code
- Another essential concept in coding is functions. Functions allow you to store a piece of code that does a single task inside a defined block, and then call that code whenever you need it using a single short command — rather than having to type out the same code multiple times. In this article we'll explore fundamental concepts behind functions such as basic syntax, how to invoke and define functions, scope, and parameters.
- Build your own function
- With most of the essential theory dealt with previously, this article provides a practical experience. Here you'll get some practice with building up your own custom function. Along the way, we'll also explain some further useful details of dealing with functions.
- Function return values
- The last essential concept you must know about a function is return values. Some functions don't return a significant value after completion, but others do. It's important to understand what their values are, how to make use of them in your code, and how to make your own custom functions return useful values.
- Introduction to events
- Events are actions or occurrences that happen in the system you are programming, which the system tells you about so you can respond to them in some way if desired. For example if the user clicks a button on a webpage, you might want to respond to that action by displaying an information box. In this final article we will discuss some important concepts surrounding events, and look at how they work in browsers.
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