Sunday 21 June 2015

Customizing Autogenerated view in entityFramework in Asp.Net MVC

In previous tutorial we learn CURD operation using EntityFramework in Asp.net MVC. When we work with entityFramework it create Views(For creation,insert,delete,update) automatically , So the output of the application is


Changes in Index View
Suppose when we get output where Header name is common for two fields then we need to change their header name for recognize ,Here if we change StudentName as “Name” then StudentName and DepartmentName has same header name as “Name then we need to customization in index view. These header name same as database table column name .
Means o/p is like below


So here i want to change the Header “student Name” instead of “Name”
Step(1):- How header generate
When we create a application using entityFramework we add a EntityDataModal then we gives connection and select tables that time it create a class in modal (Designer class).


When we go to this class we see that it’s a partial class, And this is a auto generated class .This contain all the properties (In region #region Primitive Properties) , These properties name matches with the Table column Name.

Step(2):- How to change Header name

We can change this header name either change column name in database table or change the properties name in Student class which is auto generated class.
If we change in auto generated student class is not good because due this we can loss all the changes , So we have to customization in different class.
This auto generated class is a partial class so we can create a another student partial class and we can make changes there.
So in modal folder add a class and give the name as “Student.cs” and write the following code in this class

[MetadataType(typeof(StudentMetaData))]
public partial class Student
{
}

public class StudentMetaData
{
    [Display(Name="Student Name")]

    public string Name { get; set; }

}

This display attribute present in “"System.ComponentModel.DataAnnotations" namespace

When we run this application it will generate a Header name As “StudentName” instead of Name.

Changes in Edit View
When we run this application and click on edit link then we see that “Gender” is not in dropdown and Department does not have default text.
Go to the create view and replace following code
@Html.DropDownList("DepartmentId", String.Empty)

WITH
@Html.DropDownList("DepartmentId", "Select Department")
 

For Gender

@Html.EditorFor(model => model.Gender)

WITH
@Html.DropDownList("Gender", new List<SelectListItem>

    {
    new 
SelectListItem { Text = "Male", Value="Male" },
    
new SelectListItem { Text = "Female", Value="Female" }
    }, "Select Gender")
For making Name as read only make following changes
@Html.EditorFor(model => model.Name)

TO
@Html.DisplayFor(model => model.Name)
@Html.HiddenFor(model => model.Name)

Changes in create View
Here any field is not require in create means if we click on create button it save NULL in database for all fields that is wrong, So for that we need to make require field using  [Required] attribute that present in “using System.ComponentModel.DataAnnotations;” namespace.
So lets make changes in Student class which we create as partial class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;

namespace CUROperationUsingEF.models
{
    [MetadataType(typeof(StudentMetaData))]

    public partial class Student
    {
    }

    public class StudentMetaData
    {
        [Required]
        public string Name { get; set; }

        [Required]
        public string Gender { get; set; }

        [Required]
        public string City { get; set; }

        [Required]
        [Display(Name="Department")]
        public int DepartmentId { get; set; }
    }
}

Replace the following code in Create view also
@Html.DropDownList("DepartmentId", String.Empty)

WITH
@Html.DropDownList("DepartmentId", "Select Department")
 

For Gender

@Html.EditorFor(model => model.Gender)

WITH
@Html.DropDownList("Gender", new List<SelectListItem>

    {
    new 
SelectListItem { Text = "Male", Value="Male" },
    
new SelectListItem { Text = "Female", Value="Female" }
    }, "Select Gender")


Now Run your application and click on create button and see the result.

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