LINQ is a query-like language for .NET that makes it easy to get information no matter where it comes from, and the information is retrieved the same way regardless of how or where it is stored. This sameness significantly improves productivity. In essence, LINQ provides a very clean, usable, efficient way to query data sources directly from within programming language code. LINQ is the most important new feature of Visual Studio 2008, and has been widely anticipated by developers. Larry O'Brien of SD Times calls LINQ "an important innovation that is garnering essentially unqualified raves and already being extended in fascinating new ways." As with any new technology, however, there will be a learning curve for developers wishing to use it. Linq Unleashed will be the best way for professional programmers to get the most out of LINQ. In addition to providing comprehensive coverage of LINQ's features and practical examples to show how to use those features, the author will provide enough underlying information so that you can grasp the "why" of LINQ. ------------------- Table Of Contents ------------------- Introduction 1 Part I Getting Ready for LINQ 1 Programming with Anonymous Types 5 2 Using Compound Type Initialization 29 3 Defining Extension and Partial Methods 61 4 yield return: Using .NET’s State Machine Generator 85 5 Understanding Lambda Expressions and Closures 97 6 Using Standard Query Operators 121 Part II LINQ for Objects 7 Sorting and Grouping Queries 137 8 Using Aggregate Operations 151 9 Performing Set Operations 167 10 Mastering Select and SelectMany 185 11 Joining Query Results 211 12 Querying Outlook and Active Directory 239 Part III LINQ for Data 13 Querying Relational Data with LINQ 265 14 Creating Better Entities and Mapping Inheritance and Aggregation 289 15 Joining Database Tables with LINQ Queries 309 16 Updating Anonymous Relational Data 349 17 Introducing ADO.NET 3.0 and the Entity Framework 383 Part IV LINQ for XML 18 Extracting Data from XML 415 19 Comparing LINQ to XML with Other XML Technologies 437 20 Constructing XML from Non-XML Data 453 21 Emitting XML with the XmlWriter 463 22 Combining XML with Other Data Models 469 23 LINQ to XSD Supports Typed XML Programming 485