LINQ to Objects Using C# 4.0: Using and Extending LINQ to Objects and Parallel LINQ (PLINQ), Rough Cuts
- By Troy Magennis
- Published Aug 4, 2009 by Addison-Wesley Professional.
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Description
- Copyright 2010
- Dimensions: 7 X 9-1/8
- Pages: 336
- Edition: 1st
- Rough Cuts
- ISBN-10: 0-321-63719-4
- ISBN-13: 978-0-321-63719-2
This is a working draft of a pre-release book. It is available before the published date as part of the Rough Cuts service.
“For several years, Troy has been one of the key figures in the LINQ community. This comprehensive and well-written book serves as a compendium of the important wisdom and experience that he has accumulated through his years of studying LINQ and its uses.”
–Charlie Calvert, Microsoft C# Community Program Manager
“LINQ is changing the way we think about working with data and, in many ways, also about programming in general. LINQ to Objects Using C# 4.0 is a thorough reference that teaches how to simplify many day-to-day tasks with data. It also gives you the foundations that are necessary to understand a wide range of fascinating applications of LINQ that will, no doubt, continue to appear over the next few years.”
–Tomas Petricek, Microsoft MVP and author of Real-World Functional Programming
Your Complete Example-Rich Guide to Using and Extending LINQ to Objects and PLINQ
Using LINQ to Objects, .NET developers can write queries over object collections with the same deep functionality that was once available only with SQL and relational databases. Now, for the first time, developers have a comprehensive and authoritative guide to applying LINQ to Objects in real-world software. Microsoft MVP Troy Magennis introduces state-of-the-art techniques for working with in-memory collections more elegantly and efficiently—and writing code that is exceptionally powerful, robust, and flexible.
Drawing on his unsurpassed experience coding software using LINQ and hosting the popular HookedOnLINQ.com site, Magennis presents timely, realistic solutions to a wide spectrum of development challenges, such as combining data from multiple sources, and achieving optimal performance with extremely large sets of data. You’ll begin with brief quick-starts that walk you through LINQ to Objects’ key features and query syntax. Next, you’ll drill down to detailed techniques for applying and extending these features with C# 4.0 and C# 3.0—including code examples that reflect the realities of production development.
Coverage includes
• Writing basic LINQ queries with C#: filtering, projecting, and sorting data from in-memory collections
• Mastering advanced techniques for grouping and joining data and understanding the performance implications of each technique
• Taking full advantage of LINQ’s standard query operators
• Creating custom query operators that follow best practices for coding patterns and error handling
• Writing more fluent, readable LINQ queries with C# 4.0’s language enhancements, including the new dynamic features
• Combining LINQ with COM-Interop to access data sources such as Microsoft Excel
• Using Parallel LINQ to Objects (PLINQ) to optimize queries for multi-core processors, and how to build custom parallel query operators
• Integrating the best LINQ to Objects patterns into your day-to-day coding
Sample Content
Table of Contents
Foreword . . . x
Preface . . . xii
Acknowledgments . . . xix
About the Author . . . xx
Chapter 1: Introducing LINQ . . . 1
What Is LINQ? . . . 1
The (Almost) Current LINQ Story . . . 3
LINQ Code Makeover–Before and After Code Examples . . . 5
Benefits of LINQ . . . 12
Summary . . . 15
References . . . 15
Chapter 2: Introducing LINQ to Objects . . . 17
LINQ Enabling C# 3.0 Language Enhancements . . . 17
LINQ to Objects Five-Minute Overview . . . 30
Summary . . . 39
References . . . 39
Chapter 3: Writing Basic Queries . . . 41
Query Syntax Style Options . . . 41
How to Filter the Results (Where Clause) . . . 49
How to Change the Return Type (Select Projection) . . . 54
How to Return Elements When the Result Is a Sequence (Select Many) . . . 59
How to Get the Index Position of the Results . . . 61
How to Remove Duplicate Results . . . 62
How to Sort the Results . . . 63
Summary . . . 73
Chapter 4: Grouping and Joining Data . . . 75
How to Group Elements . . . 75
How to Join with Data in Another Sequence . . . 93
Summary . . . 119
Chapter 5: Standard Query Operators . . . 121
The Built-In Operators . . . 121
Aggregation Operators–Working with Numbers . . . 123
Conversion Operators–Changing Types . . . 131
Element Operators . . . 144
Equality Operator–SequenceEqual . . . 153
Generation Operators–Generating Sequences of Data . . . 155
Merging Operators . . . 159
Partitioning Operators–Skipping and Taking Elements . . . 160
Quantifier Operators–All, Any, and Contains . . . 164
Summary . . . 171
Chapter 6: Working with Set Data . . . 173
Introduction . . . 173
The LINQ Set Operators . . . 174
The HashSet<T> Class . . . 185
Summary . . . 192
Chapter 7: Extending LINQ to Objects . . . 195
Writing a New Query Operator . . . 195
Writing a Single Element Operator . . . 196
Writing a Sequence Operator . . . 208
Writing an Aggregate Operator . . . 216
Writing a Grouping Operator . . . 222
Summary . . . 232
Chapter 8: C# 4.0 Features . . . 233
Evolution of C# . . . 233
Optional Parameters and Named Arguments . . . 234
Dynamic Typing . . . 243
COM-Interop and LINQ . . . 251
Summary . . . 260
References . . . 260
Chapter 9: Parallel LINQ to Objects . . . 261
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