Book Image

WCF 4.0 Multi-tier Services Development with LINQ to Entities

By : Mike Liu
Book Image

WCF 4.0 Multi-tier Services Development with LINQ to Entities

By: Mike Liu

Overview of this book

WCF is the Microsoft model for building services, whereas LINQ to Entities is the Microsoft ORM for accessing underlying data storage. Want to learn both? You would normally have to dig through huge reference tomes—so wouldn't you agree that a simple-to-follow practical tutorial on WCF and LINQ to Entities is the way to get ahead?This book is the quickest and easiest way to learn WCF and LINQ to Entities in Visual Studio 2010. WCF and LINQ to Entities are both powerful yet complex technologies from Microsoft—but you will be surprised at how easily this book will get you get up and running with them.Mastery of these two topics will quickly enable you to create Service-Oriented applications, and allow you to take your first steps into the world of Service Oriented Architecture without becoming overwhelmed.Through this book, you will learn what's going on behind the scenes with WCF, and dive into the basic yet most useful techniques for LINQ to Entities. You will develop three real-world multi-tiered WCF services from beginning to end, with LINQ to Entities being used in the data access layer of the services. Various clients including windows console applications, the WCF Test Client, Windows Form applications and WPF applications will be created to test these WCF services. By the end of this book, you will be 100% confident that you know WCF and LINQ to Entities, not only in theory, but with sound real-world experience.
Table of Contents (16 chapters)
WCF 4.0 Multi-tier Services Development with LINQ to Entities
Credits
About the Author
About the Reviewers
Preface
Index

Chapter 6. LINQ—Language Integrated Query

In the previous chapters of this book we created one WCF service with three layers. In the data access layer we used the raw ADO.NET SQL adapters to communicate with the Northwind database. In one of the following chapters we will explain how to use LINQ to Entities in our data access layer.

Before using LINQ to Entities in our data access layer we need to understand what LINQ or LINQ to Entities actually mean. Before understanding LINQ, we first need to understand some new C# features related to LINQ. In this chapter we will first explore these new C# features related to LINQ, then we will explore LINQ. In next two chapters we will explore LINQ to Entities, and after that we will apply LINQ to Entities to our WCF service data access layer.

In this chapter we will cover:

  • What LINQ is

  • New data type var

  • Automatic properties

  • Object initializer and Collection initializer

  • Anonymous types

  • Extension methods

  • Lambda expressions

  • Built-in LINQ extension methods and...