In this post we are going to see how we can do CRUD operations with ASP.NET MVC and PetaPoco Micro ORM.

What is PetaPoco?

Petapoco is a tiny ORM developed by topten software. As per them it’s a tiny, fast, single-file micro-ORM for .NET and Mono.

• Like Massive it's a single file that you easily add to any project
• Unlike Massive it works with strongly typed POCO's
• Like Massive, it now also supports dynamic Expandos too - read more
• Like ActiveRecord, it supports a close relationship between object and database table
• Like SubSonic, it supports generation of poco classes with T4 templates
• Like Dapper, it's fast because it uses dynamic method generation (MSIL) to assign column values to properties

Features of PetaPoco:

As per topten software it contains following features.

• Tiny, no dependencies... a single C# file you can easily add to any project.
• Works with strictly undecorated POCOs, or attributed almost-POCOs.
• Helper methods for Insert/Delete/Update/Save and IsNew
• Paged requests automatically work out total record count and fetch a specific page.
• Easy transaction support.
• Better parameter replacement support, including grabbing named parameters from object properties.
• Great performance by eliminating Linq and fast property assignment with DynamicMethod generation.
• Includes T4 templates to automatically generate POCO classes for you.
• The query language is SQL... no weird fluent or Linq syntaxes (yes, matter of opinion)
• Includes a low friction SQL builder class that makes writing inline SQL much easier.
• Hooks for logging exceptions, installing value converters and mapping columns to properties without attributes.
• Works with SQL Server, SQL Server CE, MySQL, PostgreSQL and Oracle.
• Works under .NET 3.5 or Mono 2.6 and later.
• Experimental support for dynamic under .NET 4.0 and Mono 2.8
• NUnit unit tests.
• OpenSource (Apache License)
• All of this in about 1,500 lines of code

Continue reading →

There are lots of ways to implement repository pattern but with ado.net entity model you can create repository pattern within 10 to 15 minutes.

If you are creating asp.net mvc application then just right click->Model folder->Add->Net Item->select ado.net entity data model.



From database explorer right click and drag your tables to your database explorer. It will create a entity class. For example i have created a notes table for my sample and it will create a notes entity class in my ado.net entity data model.



After creating the entity class not its time to create a interface for repository pattern which will contain my all the operations related to notes entity.

Following is the interface which we will implement use for repository.

namespace DotNetJapsMVC.Models.Respository.Interface
{
interface INotesRepository
{
void CreateNotes(Notes notesToCreate);
void EditNotes(Notes notesToEdit);
void DeleteNotes(Notes notesToDelete);
Notes GetNotes(Guid noteId);
IEnumerable ListNotes();
}
}

Now we will create a class that will implement this repository interface. Here is the coding for that.


using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace DotNetJapsMVC.Models.Respository.Class
{
public class NotesRepository:Interface.INotesRepository
{
private DotNetJapsEntities _myEntities = new DotNetJapsEntities();

public void CreateNotes(Notes notesToCreate)
{
_myEntities.AddToNotes(notesToCreate);
_myEntities.SaveChanges();
}

public void EditNotes(Notes notesToEdit)
{
var originalNotes = (from n in _myEntities.Notes
where n.NoteId == notesToEdit.NoteId
select n).FirstOrDefault();

_myEntities.ApplyPropertyChanges(originalNotes.EntityKey.EntitySetName, notesToEdit);
_myEntities.SaveChanges();

}

public void DeleteNotes(Notes notesToDelete)
{
var originalNotes = GetNotes(notesToDelete.NoteId);
_myEntities.DeleteObject(originalNotes );
_myEntities.SaveChanges();
}

public Notes GetNotes(Guid noteId)
{
return (from n in _myEntities.Notes
where n.NoteId == noteId
select n ).FirstOrDefault();
}

public IEnumerable ListNotes()
{
return _myEntities.Notes.ToList();
}

}
}

That's it we have created the repository classes and repository interface. You can use as following in your class or pages.

private  INotesRepository _repository;

public List LoadNotes()
{
 return _repository.ListNotes();
}

Advantage Of Repository Pattern:

1. Make application loosely coupled so if you want to change the something then you don't need to change everything from scratch.
2. With the repository pattern we can have nice abstraction which will separate our business logic as well as database logic.
3. You can prevent dependency injection through the repository pattern.
   

Happy Programming

There are lots of ORM(Object Relational Mapper) tools are available for the Microsoft.NET like linq 2 sql, ado.net entity framework, nhibernate, subsonic and so many others. Developer often confuses which technlogy he should choose but i think a developer should deternmine his requiremnt first then he has check the pros and cons of every tool there .

I have used ado.net entity framework for my application as i like it most and its easy to use.
Following are some good article which will help you to choose right orm tool for your applications.

http://ayende.com/Blog/archive/2007/06/03/On-SubSonic-amp-NHibernate.aspx

http://blog.wekeroad.com/blog/aspnet-mvc-choosing-your-data-access-method/

http://dotnet.netindonesia.net/?0::41743

http://geekswithblogs.net/diadiora/archive/2009/01/12/best-.net-orm-tool.aspx

http://madgeek.com/Articles/ORMapping/EN/mapping.htm

Happy Programming...