Book Image

NHibernate 4.x Cookbook - Second Edition

By : Gunnar Liljas, Alexander Zaytsev, Jason Dentler
Book Image

NHibernate 4.x Cookbook - Second Edition

By: Gunnar Liljas, Alexander Zaytsev, Jason Dentler

Overview of this book

NHibernate is a mature, flexible, scalable, and feature-complete open source project for data access. Although it sounds like an easy task to build and maintain database applications, it can be challenging to get beyond the basics and develop applications that meet your needs perfectly. NHibernate allows you to use plain SQL and stored procedures less and keep focus on your application logic instead. Learning the best practices for a NHibernate-based application will help you avoid problems and ensure that your project is a success. The book will take you from the absolute basics of NHibernate through to its most advanced features, showing you how to take full advantage of each concept to quickly create amazing database applications. You will learn several techniques for each of the four core NHibernate tasks—configuration, mapping, session and transaction management, and querying—and which techniques fit best with various types of applications. In short, you will be able to build an application using NHibernate by the end of the book. You will also learn how to best implement enterprise application architecture patterns using NHibernate, leading to clean, easy-to-understand code and increased productivity. In addition to new features, you will learn creative ways to extend the NHibernate core, as well as gaining techniques to work with the NHibernate search, shards, spatial, envers, and validation projects.
Table of Contents (17 chapters)
NHibernate 4.x Cookbook Second Edition
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Using custom functions in LINQ


In this recipe, we will show you how to map database functions and stored procedures to LINQ functions.

Getting ready

Complete the previous recipe, Using custom dialect functions.

How to do it…

  1. Create a new class library project named CustomLinqGenearatorExample.

  2. Install the NHibernate and log4net packages using the NuGet Package Manager Console by executing the following command:

    Install-Package NHibernate
    Install-Package log4net
    
  3. Create the SqlFunctions class using the following code:

    public static class SqlFunctions
    {
      [LinqExtensionMethod]
      public static DateTime AddDays(DateTime dt, int d)
      {
        return dt.AddDays(d);
      }
    
      [LinqExtensionMethod]
      public static DateTime AddHours(DateTime dt, int h)
      {
        return dt.AddHours(h);
      }
    
      [LinqExtensionMethod]
      public static DateTime AddMinutes(DateTime dt, int m)
      {
        return dt.AddMinutes(m);
      }
    
      [LinqExtensionMethod]
      public static DateTime AddSeconds(DateTime dt, int s)
      {
        return dt.AddSeconds...