Book Image

HTML5 Web Application Development By Example : Beginner's guide

By : Jody Gustafson
Book Image

HTML5 Web Application Development By Example : Beginner's guide

By: Jody Gustafson

Overview of this book

HTML5's new features have made it a real application development platform with widespread adoption throughout the industry for this purpose. Being able to create one application that can run on virtually any device from phone to desktop has made it the first choice among developers. Although JavaScript has been around for a while now, it wasn't until the introduction of HTML5 that we have been able to create dynamic, feature-rich applications rivaling those written for the desktop. HTML5 Web Application Development By Example will give you the knowledge you need to build rich, interactive web applications from the ground up, incorporating the most popular HTML5 and CSS3 features available right now. This book is full of tips, tools, and example applications that will get you started writing your own applications today. HTML5 Web Application Development By Example shows you how to write web applications using the most popular HTML5 and CSS3 features. This book is a practical, hands-on guide with numerous real-world and relevant examples. You will learn how to use local storage to save an application's state and incorporate CSS3 to make it look great. You will also learn how to use custom data attributes to implement data binding. We'll use the new Canvas API to create a drawing application, then use the Audio API to create a virtual piano, before turning it all into a game. The time to start using HTML5 is now. And HTML5 Web Application Development by Example will give you the tips and know-how to get started.
Table of Contents (18 chapters)
HTML5 Web Application Development By Example Beginner's guide
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

The File API


We may not be able to save files directly to the user's filesystem, but we can access files using HTML5's File API. The File API allows you to get information about, and load the contents of, files that the user selects. The user can select files using an input element with a type of file. The process for loading a file works in the following way:

  1. The user selects one or more files using a <input type="file"> element.

  2. We get the list of files from the input element's files property. The list is a FileList object containing File objects.

  3. You can enumerate over the file list and access the files just like you would an array.

    The File object contains three fields.

    • name: This is the filename. It doesn't include path information.

    • size: This is the size of the file in bytes.

    • type: This is the MIME type, if it can be determined.

  4. Use a FileReader object to read the file's data. The file is loaded asynchronously. After the file has been read, it will call the onload event handler. FileReader...