如何在Linq使用case

zzh198310 2008-01-11 05:38:34
在LINQ语法中如何对于select进行case语法
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liuning623 2008-05-12
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我也碰到的同样的问题不知道怎么解决,不过有一个变通的方法,可以自己写一个函数来做处理。
zzh198310 2008-01-14
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你那个只不过是2种解决方法而已。。如果要3种以上的呢???
heguo 2008-01-12
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var q =
from p in db.Products
select new {p.ProductName, Availability = p.UnitsInStock - p.UnitsOnOrder < 0 ? "Out Of Stock": "In Stock"};
LINQ is one of Microsoft’s most exciting, powerful new development technologies. Essential LINQ is the first LINQ book written by leading members of Microsoft’s LINQ and C# teams. Writing for architects, developers, and development managers, these Microsoft insiders share their intimate understanding of LINQ, revealing new patterns and best practices for getting the most out of it. Calvert and Kulkarni begin by clearly explaining how LINQ resolves the long-time “impedance mismatch” between object-oriented code and relational databases. Next, they show how LINQ integrates querying into C# as a “first-class citizen.” Using realistic code examples, they show how LINQ provides a strongly typed, IntelliSense-aware technology for working with data from any source, including SQL databases, XML files, and generic data structures. Calvert and Kulkarni carefully explain LINQ’s transformative, composable, and declarative capabilities. By fully illuminating these three concepts, the authors allow developers to discover LINQ’s full power. In addition to covering core concepts and hands-on LINQ development in C# with LINQ to Objects, LINQ to XML, LINQ to SQL, and LINQ to Entities, they also present advanced topics and new LINQ implementations developed by the LINQ community. This book • Explains the entire lifecycle of a LINQ project: design, development, debugging, and much more • Teaches LINQ from both a practical and theoretical perspective • Leverages C# language features that simplify LINQ development • Offers developers powerful LINQ query expressions to perform virtually any data-related task • Teaches how to query SQL databases for objects and how to modify those objects • Demonstrates effective use stored procedures and database functions with LINQ • Shows how to add business logic that reflects the specific requirements of your organization • Teaches developers to create, query, and transform XML data with LINQ • Shows how to transform object, relational, and XML data between each other • Offers best patterns and practices for writing robust, easy-to-maintain LINQ code About the Author Charlie Calvert, Community Program Manager for the Microsoft C# team, currently focuses his technical energies on LINQ. He has periodically worked with LINQ Chief Architect Anders Hejlsberg both during the development of Delphi and during the development of LINQ. Calvert’s ten technical books have sold more than 100,000 copies. They include Delphi 4 Unleashed, C++Builder 3 Unleashed, Delphi 2 Unleashed, Teach Yourself Windows 95 Programming in 21 Days, and Teach Yourself Windows Programming. Dinesh Kulkarni is a Senior Program Manager on Microsoft’s .NET Framework team. He was the Program Manager in charge of LINQ to SQL. He was deeply involved in LINQ’s planning and implementation from the incubation stage and was lead author for MSDN’s authoritative LINQ to SQL paper. Before joining Microsoft, he worked in diverse technical roles ranging from architecting and implementing front-end CASE tools for IBM to designing databases and middleware for a Wall Street hedge fund. Product Details Paperback: 600 pages Publisher: Addison-Wesley Professional; 1 edition (March 22, 2009) Language: English ISBN-10: 0321564162 ISBN-13: 978-0321564160
Book Description The professional programmer’s Deitel® guide to C# 2010 and the powerful Microsoft® .NET 4 Framework Written for programmers with a background in C++, Java or other high-level, object-oriented languages, this book applies the Deitel signature live-code approach to teaching programming and explores Microsoft’s C# 2010 language and .NET 4 in depth. The book is updated for Visual Studio® 2010 and C# 4, and presents C# concepts in the context of fully tested programs, complete with syntax shading, detailed line-by-line code descriptions and program outputs. The book features 200+ C# applications with 17,000+ lines of proven C# code, as well as hundreds of programming tips that will help you build robust applications. Start with a concise introduction to C# fundamentals using an early classes and objects approach, then rapidly move on to more advanced topics, including multithreading, .NET 4, LINQ, WPF, ASP.NET 4, WCF web services and Silverlight®. Along the way you’ll enjoy the Deitels’ classic treatment of object-oriented programming and the OOD/UML® ATM case study, including a complete C# implementation. When you’re finished, you’ll be ready to build next-generation Windows applications, web applications and web services. Check out the related LiveLessons video product, C# 2010 Fundamentals: Parts I, II and III, containing 20+ hours of video synchronized to this book: www.deitel.com/livelessons. Practical, example-rich coverage of: .NET 4, Types, Arrays, Exception Handling LINQ, Object/Collection Initializers OOP: Classes, Objects, Inheritance, Polymorphism, Interfaces WinForms, WPF, XAML, Event Handling WPF GUI/Graphics/Multimedia Silverlight® Lists, Queues, Stacks, Trees Generic Collections, Methods and Classes XML®, LINQ to XML Database, LINQ to SQL ASP.NET 4.0, ASP.NET AJAX Web Forms, Web Controls WCF Web Services OOD/UML® Case Study About the Author Paul Deitel and Harvey Deitel are the founders of Deitel & Associates, Inc., th

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