Book Image

Opa Application Development

By : Li Wenbo
Book Image

Opa Application Development

By: Li Wenbo

Overview of this book

Opa is a full-stack Open Source web development framework for JavaScript that lets you write secure and scalable web applications. It generates standard Node.js/MongoDB applications, natively supports HTML5 and CSS and automates many aspects of modern web application programming. It handles all aspects of web programming written in one consistent language and compiled to web standards.Opa Application Development is a practical,hands-on guide that provides you with a number of step-by-step exercises. It covers almost all aspects of developing a web application with Opa, which will help you take advantage of the real power of Opa, as well as building a secure, powerful web application rapidly.Opa Application Development dives into all concepts and components required to build a web application with Opa. The first half of this book shows you all of the basic building blocks that you will need to develop an Opa application, including the syntax of Opa, web development aspects, client and server communication and slicing, plugin, database, and so on. By the end of the book you will have yourself created a complete web application along with a game: Pacman!
Table of Contents (18 chapters)
Opa Application Development
About the Author
About the Reviewers

Manipulating DOMs

The Document Object Model (DOM) is a platform and language neutral interface that allows programs and scripts to dynamically access and update the content, structure, and style of documents.

At times, we may want to change the content of a page dynamically. To accomplish this, we will often need to interact with the DOM. Opa provides the module Dom for the purpose of manipulating the contents of the page currently being displayed by the browser. You can use it to add and remove elements to and from the page, to get the contents of a form, or to apply styles or special effects.

DOM selection

The first step that is necessary, in order to use DOMs, is to select the one that you want to work with. Opa provides many ways of selecting elements. You can find all the available selection functions in the module Dom. The most commonly used ones are:

Dom.select_id("id")          //select element with a given id
Dom.select_document()        //select the complete document