Book Image

Entity Framework Tutorial (Update) - Second Edition

By : Joydip Kanjilal
Book Image

Entity Framework Tutorial (Update) - Second Edition

By: Joydip Kanjilal

Overview of this book

The ADO.NET Entity Framework from Microsoft is a new ADO.NET development framework that provides a level of abstraction for data access strategies and solves the impedance mismatch issues that exist between different data models This book explores Microsoft’s Entity Framework and explains how it can used to build enterprise level applications. It will also teach you how you can work with RESTful Services and Google’s Protocol Buffers with Entity Framework and WCF. You will explore how to use Entity Framework with ASP.NET Web API and also how to consume the data exposed by Entity Framework from client applications of varying types, i.e., ASP.NET MVC, WPF and Silverlight. You will familiarize yourself with the new features and improvements introduced in Entity Framework including enhanced POCO support, template-based code generation, tooling consolidation and connection resiliency. By the end of the book, you will be able to successfully extend the new functionalities of Entity framework into your project.
Table of Contents (16 chapters)
Entity Framework Tutorial Second Edition
About the Author
About the Reviewers

Querying data using LINQ

Let's take a look at how we can use LINQ to query data in our applications. The following code snippet illustrates how you can use LINQ to display the contents of an array:

String[] employees = {"Joydip", "Douglas", "Jini", "Piku", "Amal",
                      "Rama", "Indronil"};
var employeeNames = from employee in employees select employee;
foreach (var empName in employeeNames)

Now, let's discuss how to use LINQ to query a generic list. Consider the following GenericEmployeeList list:

public List<String> GenericEmployeeList = new List<String>()
  "Joydip", "Douglas", "Jini", "Piku",
  "Rama", "Amal", "Indronil"

You can use LINQ to query this list as shown in the following code snippet:

IEnumerable<String> employees = from emp in GenericEmployeeList
   select emp;
  foreach (string employee in employees)

You can use conditions with your LINQ query as well. The following example...