Libro sobre php

THE EXPERT’S VOICE ® IN OPEN SOURCE

PHP Objects, Patterns, and Practice
Build powerful code by mastering PHP’s object-oriented enhancements, design patterns, and essential development tools

THIRD EDITION

Matt Zandstra

PHP Objects, Patterns, and Practice
Third Edition

■■■ Matt Zandstra

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PHP Objects, Patterns, and Practice, Third Edition Copyright © 2010 by MattZandstra All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher. ISBN-13 (pbk): 978-1-4302-2925-4 ISBN-13 (electronic): 978-1-4302-2926-1 Printed and bound in theUnited States of America 9 8 7 6 5 4 3 2 1 Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. President and Publisher: Paul Manning Lead Editor: Michelle Lowman, Matt Wade TechnicalReviewer: Wes Hunt Editorial Board: Clay Andres, Steve Anglin, Mark Beckner, Ewan Buckingham, Gary Cornell, Jonathan Gennick, Jonathan Hassell, Michelle Lowman, Matthew Moodie, Duncan Parkes, Jeffrey Pepper, Frank Pohlmann, Douglas Pundick, Ben Renow-Clarke, Dominic Shakeshaft, Matt Wade, Tom Welsh Coordinating Editor: Jim Markham Copy Editor: Tracy Brown Collins Compositor: MacPS, LLC Indexer: TomaMulligan Artist: April Milne Cover Designer: Anna Ischenko Distributed to the book trade worldwide by Springer-Verlag New York, Inc., 233 Spring Street, 6th Floor, New York, NY 10013. Phone 1-800-SPRINGER, fax 201-348-4505, e-mail orders-ny@springer-sbm.com, or visit www.springeronline.com. For information on translations, please e-mail info@apress.com, or visit www.apress.com. Apress and friendsof ED books may be purchased in bulk for academic, corporate, or promotional use. eBook versions and licenses are also available for most titles. For more information, reference our Special Bulk Sales–eBook Licensing web page at www.apress.com/info/bulksales. The information in this book is distributed on an “as is” basis, without warranty. Although every precaution has been taken in thepreparation of this work, neither the author(s) nor Apress shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this work. The source code for this book is available to readers at www.apress.com. You will need to answer questions pertaining to this book in order to successfully downloadthe code.

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Contents at a Glance

■Contents at a Glance.......................................................................................................................iii ■Contents .......................................................................................................................................... v ■About the Author......................................................................................................................... xvii ■About the Technical Reviewer .................................................................................................... xviii ■Acknowledgments ........................................................................................................................ xix ■Introduction to the ThirdEdition ................................................................................................... xx Part 1: Introduction.............................................................................................................................1 ■Chapter 1: PHP: Design and Management .......................................................................................3 Part 2: Objects...