Book Image

Entity Framework Core Cookbook - Second Edition

By : Ricardo Peres
Book Image

Entity Framework Core Cookbook - Second Edition

By: Ricardo Peres

Overview of this book

Entity Framework is a highly recommended Object Relation Mapping tool used to build complex systems. In order to survive in this growing market, the knowledge of a framework that helps provide easy access to databases, that is, Entity Framework has become a necessity. This book will provide .NET developers with this knowledge and guide them through working efficiently with data using Entity Framework Core. You will start off by learning how to efficiently use Entity Framework in practical situations. You will gain a deep understanding of mapping properties and find out how to handle validation in Entity Framework. The book will then explain how to work with transactions and stored procedures along with improving Entity Framework using query libraries. Moving on, you will learn to improve complex query scenarios and implement transaction and concurrency control. You will then be taught to improve and develop Entity Framework in complex business scenarios. With the concluding chapter on performance and scalability, this book will get you ready to use Entity Framework proficiently.
Table of Contents (15 chapters)
Entity Framework Core Cookbook - Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Validating groups of entities


We've seen how we can validate single properties or entities, but what if we need to validate several entities at the same time? This may be because we cannot allow duplicate values, or for any other reason. Let's look at a possible solution.

We will be using NuGet Package Manager to install the Entity Framework Core 1 package, Microsoft.EntityFrameworkCore. We will also be using a SQL Server database for storing the data, so we will also need Microsoft.EntityFrameworkCore.SqlServer.

Finally, xunit is the package we will be using for the unit tests and dotnet-text-xunit adds tooling support for Visual Studio. Note that the UnitTests project is a .NET Core App 1.0 (netcoreapp1.0), where Microsoft.EntityFrameworkCore.Design is configured as a build dependency and Microsoft.EntityFrameworkCore.Tools is set as a tool.

Open Using EF Core Solution from the included source code examples.

Execute the database setup script from the code samples included with this recipe...