Using OData features in a ASP.NET MVC Web API using Visual Studio 2012

In this article we will focus on how to use the OData features in a ASP.NET MVC Web API using Visual Studio 2012.

What is OData:
OData is a Data Access Protocol.

Why to use OData:
•It provides a uniform way to query the data, perform different operations against the data such as insert/update/delete/select
•It supports different formats such as JSON/XML.
•Using OData we can also easily expose metadata about the data which can be used by clients to discover type information and relationships between different entities.
• It provides additional features on top of the basic functionality such as filtering the records based on some condition, paging, sorting, retrieving selective number of records and many more in a very easy manner.

OData in action
We will create a simple WebAPI OData project which allows us to perform simple operations like filtering the data, selecting first few records, sorting the records by a particular column.

Step 1
Launch Visual Studio 2012 -> File -> New -> Project -> ASP.NET MVC4 Web Application -> Select Empty Template -> click Ok.
Step 2
Right click Models folder and add a new class with the name "Emp". Add Id,Name,Salary properties to this class.

 public class Emp
    {
        public int ID { get; set; }
        public string Name { get; set; }
        public decimal Salary { get; set; }

    }

public class EmpController : ApiController
    {
        [Queryable]
        public IQueryable Get()
        {
            List lstEmp = new List();
            lstEmp.Add(new Emp { ID = 1, Name = "Priya", Salary = 5000 });
            lstEmp.Add(new Emp { ID = 2, Name = "Reena", Salary = 15000 });
            lstEmp.Add(new Emp { ID = 3, Name = "John", Salary = 25000 });
            lstEmp.Add(new Emp { ID = 4, Name = "Nita", Salary = 1000 });
            lstEmp.Add(new Emp { ID = 5, Name = "Sam", Salary = 62000 });
            lstEmp.Add(new Emp { ID = 6, Name = "Robert", Salary = 8000 });
            lstEmp.Add(new Emp { ID = 7, Name = "Sakshi", Salary = 9000 });
            lstEmp.Add(new Emp { ID = 8, Name = "Kate", Salary = 25000 });
            return lstEmp.AsQueryable();
        }
    }