Part 40 - Using displayname, displayformat, scaffoldcolumn attributes in asp.net mvc application

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In this video, we will discuss using the following attributes, with examples. 
1. Display
2. DisplayName
3. DisplayFormat
4. ScaffoldColumn



We will be using table tblEmployee for this demo. 
Create table tblEmployee
(
Id int primary key identity,
FullName nvarchar(100),
Gender nvarchar(10),
Age int,
HireDate DateTime,
EmailAddress nvarchar(100),
Salary int,
PersonalWebSite nvarchar(100)
)



Insert into tblEmployee values
('John Smith', 'Male', 35, '2007-01-02 17:53:46.833', 'JohnSmith@pragimtech.com', 45000, 'http://www.pragimtech.com')
Insert into tblEmployee values
('Mary Jane', NULL, 30, '2009-05-02 19:43:25.965', 'MaryJane@pragimtech.com', 35000, 'http://www.pragimtech.com')

Generate ADO.NET entity data model for table tblEmployee. Change the entity name from tblEmployee to Employee. Save and build the project.

Right click on the "Controllers" folder and add "HomeController". Include the following "USING" statement.
using MVCDemo.Models;

Copy and paste the following code.
public class HomeController : Controller
{
    public ActionResult Details(int id)
    {
        SampleDBContext db = new SampleDBContext();
        Employee employee = db.Employees.Single(x => x.Id == id);
        return View(employee);
    }
}

Right click on the "Details" action method, and add "Details" view. Make sure you are creating a strongly typed view against "Employee" class. Select "Details" as the "Scaffold Template". Run the application and notice that, the output is not that pretty.

We can control the display of data in a view using display attributes that are found in System.ComponentModel.DataAnnotations namespace. It is not a good idea, to add display attributes to the properties of auto-generated "Employee" class, as our changes will be lost, if the class is auto-generated again.

So, let's create another partial "Employee" class, and decorate that class with the display attributes.  Right click on the "Models" folder and add Employee.cs class file. Copy and paste the following code.
namespace MVCDemo.Models
{
    [MetadataType(typeof(EmployeeMetaData))]
    public partial class Employee
    {
    }

    public class EmployeeMetaData
    {
        //If you want "FullName" to be displayed as "Full Name", 
        //use DisplayAttribute or DisplayName attribute.
        //DisplayName attribute is in System.ComponentModel namespace.
        //[DisplayAttribute(Name="Full Name")]
        //[Display(Name = "Full Name")]
        [DisplayName("Full Name")]
        public string FullName { get; set; }

        //To get only the date part in a datetime data type
        //[DisplayFormat(DataFormatString = "{0:d}")]
        //[DisplayFormatAttribute(DataFormatString="{0:d}")]

        //To get time in 24 hour notation
        //[DisplayFormat(DataFormatString = "{0:dd/MM/yyyy HH:mm:ss}")]

        //To get time in 12 hour notation with AM PM
        [DisplayFormat(DataFormatString = "{0:dd/MM/yyyy hh:mm:ss tt}")]
        public DateTime? HireDate { get; set; }

        // If gender is NULL, "Gender not specified" text will be displayed.
        [DisplayFormat(NullDisplayText = "Gender not specified")]
        public string Gender { get; set; }

        //If you don't want to display a column use ScaffoldColumn attribute.
        //This only works when you use @Html.DisplayForModel() helper
        [ScaffoldColumn(false)]
        public int? Salary { get; set; }
    }
}

Make sure to include the following using statements:
using System.ComponentModel.DataAnnotations;
using System.ComponentModel;

We will discuss the following attributes in our next video session.
DataTypeAttribute, 
DisplayColumnAttribute