CYAN MAGENTA YELLOW BLACK PANTONE 123 C Books for professionals by professionals ® Pro LINQ: Language Integrated Query in C# 2008 Dear Reader, Joseph C Rattz, Jr THE APRESS ROADMAP Accelerated C# 2008 Beginning C# 2008 Pro C# 2008 and the NET 3.5 Platform Silverlight and NET 3.5 Recipes in C# 2008 Beginning C# 2008 Databases Pro LINQ: Language Integrated Query in C# 2008 Pro NET 3.5 Scalable Application Design Beginning ASP.NET 3.5 Data Access, 2e Pro WPF in C# 2008, 2e Expert Service-Oriented Architecture, 3e Companion eBook See last page for details on $10 eBook version Companion eBook Available Pro Language Integrated in C# 2008 LINQ Query Pro LINQ: Language Integrated Query in C# 2008 is all about code Literally, this book starts with code and ends with code In writing this book, it has been my desire to create a treasury of meaningful LINQ examples Rather than show you a single, simplest case example, I’ve strived to fill in the whole picture and demonstrate the breadth of LINQ operators and prototypes that are available to you With this information, you will be able to put LINQ to use as it was intended and reap the maximum rewards for your investment Throughout this book, it is my aim to give you the information that actually matters in a form that you can use So, rather than obscure the relevant LINQ principles by focusing on a complex demonstration application you can’t put to practical use, Pro LINQ cuts right to the chase of each LINQ operator, method, or class However, where complexity is necessary to truly demonstrate an issue, the examples are right there in the thick of it For example, code samples demonstrating how to handle concurrency conflicts actually create concurrency conflicts, so you can step through the code and see them unfold This book is for anyone with an elementary understanding of C# who wants to understand LINQ and LINQ-relevant C# 3.0 language features You need not be up on all the latest C# 2.0 or 3.0 features to understand Pro LINQ When a deeper knowledge of an advanced language feature is necessary, I begin from the ground up to make sure everyone is well equipped for the discussion The EXPERT’s VOIce ® in NET Pro LINQ Language Integrated Query in C# 2008 Learn to use the power of Microsoft’s ground-breaking new technology Illustrated C# 2008 SOURCE CODE ONLINE www.apress.com Joseph C Rattz, Jr ISBN-13: 978-1-59059-789-7 ISBN-10: 1-59059-789-3 54499 US $44.99 Rattz Shelve in Programming/C# User level: Intermediate–Advanced 781590 597897 this print for content only—size & color not accurate spine = 1.176" 624 page count Rattz_789-3FRONT.fm Page i Thursday, October 25, 2007 8:59 AM Pro LINQ Language Integrated Query in C# 2008 ■■■ Joseph C Rattz, Jr Rattz_789-3FRONT.fm Page ii Thursday, October 25, 2007 8:59 AM Pro LINQ: Language Integrated Query in C# 2008 Copyright © 2007 by Joseph C Rattz, Jr 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): 978-1-59059-789-7 ISBN-10 (pbk): 1-59059-789-3 Printed and bound in the United States of America 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 Lead Editor: Ewan Buckingham Technical Reviewer: Fabio Ferracchiati Editorial Board: Steve Anglin, Ewan Buckingham, Tony Campbell, Gary Cornell, Jonathan Gennick, Jason Gilmore, Kevin Goff, Jonathan Hassell, Matthew Moodie, Joseph Ottinger, Jeffrey Pepper, Ben Renow-Clarke, Dominic Shakeshaft, Matt Wade, Tom Welsh Senior Project Manager: Tracy Brown Collins Copy Editors: Heather Lang and Jennifer Whipple Associate Production Director: Kari Brooks-Copony Production Editor: Katie Stence Compositor: Pat Christenson Proofreader: Dan Shaw Indexer: Carol Burbo Artist: Kinetic Publishing Services, LLC Cover Designer: Kurt Krames Manufacturing Director: Tom Debolski 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 http://www.springeronline.com For information on translations, please contact Apress directly at 2855 Telegraph Avenue, Suite 600, Berkeley, CA 94705 Phone 510-549-5930, fax 510-549-5939, e-mail info@apress.com, or visit http:// www.apress.com The information in this book is distributed on an “as is” basis, without warranty Although every precaution has been taken in the preparation 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 http://www.apress.com You will need to answer questions pertaining to this book in order to successfully download the code Rattz_789-3FRONT.fm Page iii Thursday, October 25, 2007 8:59 AM For my amazing wife Vickey, who managed to keep our house a home all by herself for these past, long 17 months Thank you for doing the things that gave me time to work on this book Rattz_789-3INDEX.fm Page 599 Wednesday, October 31, 2007 3:06 PM ■I N D E X XComment.Value, on XComment objects, 250 XElement.SetAttributeValue() method, 262–263 XContainer class, creating containers with, 210 XElement.SetElementValue() method, 253–255 XContainer.Add() (AddLast) method, 243 XElement.Value, on XElement objects 250 XContainer.AddFirst() method, 243–244 XElement.XElement(XName name, object content); 206 XContainer.Descendants() method, traversing 236–237 XContainer.Elements() method, 232–234 vs Extensions.Elements operator, 273–274 XLinq See LINQ to XML XML additional capabilities, 301–336 XContainer.Nodes() method, 228–229 desired structure, 188 XDeclaration class, 210–211 LINQ to, 187–192 XDocument class, 212–213 querying with XPath syntax, 335 XDocument.Load() method, 220–222 simple example, 187–188 XML annotations, 263–267 XDocumentType class, 211–212 XML attributes, 255–263 XDocumentType.InteralSubset, 251 XML data XDocumentType.Name, 251 modifying, 242–253 XDocumentType.PublicId, 251 query joining database data with, 583 XElement class, XElement object accessing XML document from, 226–227 instantiating, 206 traversing down recursively from, 236–237 traversing up from, 227–228, 235–236 XElement.AddFirst method, 215 XElement.AncestorsAndSelf() method, 235–236 XElement.Attribute() method, 257–258 XElement.Attributes() method, 258 XElement.DescendantsAndSelf() method, 237–238 XML documents See also documents allowing user edit of book participant, 331–332 creating for validating, 330–331 creating new for transformed version, 311 creating with book participants, 311 transforming using function construction, 312–314 transforming with XSLT, 310–311 unsuccessfully validating against XSD schema, 325–329 unsuccessfully validating XML element, 332–334 validating, 322–325, 331 XElement.FirstAttribute property, 255 XML element, successfully validating, 330 XElement.LastAttribute property, 257 XML events XElement.Load() method, 222–223 examples, 268–272 XElement.RemoveAll() method, 249 registering for, 267 XElement.ReplaceAll() method, 252–253 XML external mapping, file schema, 484–485 XElement.Save() methods, 219–220 XML input, 220–222 Find it faster at http://superindex.apress.com XDocument.Save() methods, 218–219 XDocumentType.SystemId, 251 599 Rattz_789-3INDEX.fm Page 600 Wednesday, October 31, 2007 3:06 PM 600 ■I N D E X XML mapping files XNamespace class, 214 abbreviated external, 517–518 XNode.AddAfterSelf() method, 246 considerations for using, 393 XNode.AddBeforeSelf() method, 244–245 vs DBML intermediate file, 398 XNode.Ancestors() method, 234–235 XML namespaces See namespaces XNode.ElementsAfterSelf() method, 239–240 XML output, 218–220 XNode.ElementsBeforeSelf() method, 241–242 XML schema XNode.NextNode property, 225 creating, 321–322 XNode.NodesAfterSelf() method, 238–239 creating using functional construction, 194–195 XNode.NodesBeforeSelf() method, 240–241 obtaining, 321–334 XML strings, parsing, 223 XML transformations See also transformations simplifying with helper methods, 314 tips for performing, 314–319 XML traversal, 224–242 properties, 225–228 XML tree XNode.PreviousNode property, 225–226 XNode.Remove() method247–248 XNodeDocumentOrderComparer class, 202 XNodeEqualityComparer class, 202 XObject event handling, 269–272 XObject.AddAnnotation() method, 263 XObject.Annotation()/XObject.Annotations() method, 263 XObject.Changed event, 268 adding nodes to, 242–243 XObject.Changing event, 268 for examples in LINQ to XML, 312 XObject.Document property, accessing XML document via, 226–227 generating with a LINQ query, 207–208 problems removing nodes from, 203–205 producing, 200 recursively traversing up, 234–235 traversing backward, 225–226 traversing down, 228–229 traversing forward through, 225 XML tree construction deferred execution of, 217 immediate execution of, 216 XObject.Parent property, 227–228 XObject.RemoveAnnotations() method, 264 XProcessingInstruction class, 214–215 XProcessingInstruction.Data, 252 XProcessingInstruction.Target, 252 XSLT trasformations, advantages of, 309–310 XStreamingElement class, 216–217 XText object, creating text node with, 217–218 XText.Value, on XText objects, 250 XMLHelper method, 191 ■Y XmlMappingSource object, 518 yield keyword, for writing enumerators, 55 XName object [Your]DataContext class, 499–500 creating, 213 for XML elements, 198–199 constructor prototype connecting to database, 511–512 ... Thursday, October 25, 2007 8:59 AM Pro LINQ Language Integrated Query in C# 2008 ■■■ Joseph C Rattz, Jr Rattz_789-3FRONT.fm Page ii Thursday, October 25, 2007 8:59 AM Pro LINQ: Language Integrated Query. .. property, accessing XML document via, 226–227 generating with a LINQ query, 207–208 problems removing nodes from, 203–205 producing, 200 recursively traversing up, 234–235 traversing backward, 225–226... method, 264 XProcessingInstruction class, 214–215 XProcessingInstruction.Data, 252 XProcessingInstruction.Target, 252 XSLT trasformations, advantages of, 309–310 XStreamingElement class, 216–217