Editing a Model in ASP.NET MVC

[HttpGet]
public ActionResult Edit(int id)
{
    EmployeeBusinessLayer employeeBusinessLayer = new EmployeeBusinessLayer();
    Employee employee = employeeBusinessLayer.GetAllEmployess().FirstOrDefault(emp => emp.ID == id);
    return View(employee);
}

Points to note:

1. This method is decorated with the [HttpGet] attribute. So this method only responds to HTTP get requests when editing the data.
2. The Edit action method also receives the id of the employee that is being edited. This “id” is used to retrieve the employee details.
3. The employee object is passed to the view

Step2: Creating the “Edit” view

Now let’s add the Edit view. To do this right-click on the Edit action method and then select Add View option from the context menu and then Set

View name = “Edit”
Template = “Edit”
Model class = Employee (BusinessLayer)

Click on the “Add” button as shown below. This should add the “Edit.cshtml” view within the “Employee” folder which is within the “Views” folder.

Run the application and navigate to http://localhost:54094/Employee/Index. This page should display the list of all the employees. Click on the “Edit” link which is available on the right side of the employee. The “Edit” page should display the details of the “Employee” that is being edited as shown below.

Notice that by default “textboxes” are used for editing. It is ideal to have a drop-down list for gender rather than a textbox. To achieve this make the following changes to “Edit.cshtml”.

With the above changes in place, the complete code in Edit.cshtml view as below.

@model BusinessLayer.Employee

@{
    ViewBag.Title = "Edit";
}

<h2>Edit</h2>

@using (Html.BeginForm())
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>Employee</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        @Html.HiddenFor(model => model.ID)

        <div class="form-group">
            @Html.LabelFor(model => model.Name, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Name, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Name, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Gender, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.DropDownList("Gender", new List<SelectListItem>
{
   new SelectListItem { Text = "Male", Value="Male" },
   new SelectListItem { Text = "Female", Value="Female" }
}, "Select Gender", new { @class = "form-control" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.City, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.City, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.City, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Salary, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Salary, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Salary, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.DateOfBirth, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.DateOfBirth, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.DateOfBirth, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Save" class="btn btn-default" />
            </div>
        </div>
    </div>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

<script src="~/Scripts/jquery-1.10.2.min.js"></script>
<script src="~/Scripts/jquery.validate.min.js"></script>
<script src="~/Scripts/jquery.validate.unobtrusive.min.js"></script>

Run the application. Edit an employee, and notice that a DropDownList is used for gender as expected.

Create a stored procedure to update employee data.

Create procedure spUpdateEmployee      
  @Id int,
  @Name nvarchar(50),      
  @Gender nvarchar (10),      
  @City nvarchar (50), 
  @Salary decimal(18,2),     
  @DateOfBirth DateTime 
as      
Begin      
  Update Employee Set
    Name = @Name,
    Gender = @Gender,
    City = @City,
    Salary = @Salary,
    DateOfBirth = @DateOfBirth
  Where   Id = @Id
End

Add the following “UpdateEmployee()” method to the “EmployeeBusinessLayer” class in the “BusinessLayer” project.

This method is used to update employee data to the database table.

public void UpdateEmmployee(Employee employee)
{
    string connectionString = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

    using (SqlConnection con = new SqlConnection(connectionString))
    {
        SqlCommand cmd = new SqlCommand("spUpdateEmployee", con);
        cmd.CommandType = CommandType.StoredProcedure;

        SqlParameter paramId = new SqlParameter();
        paramId.ParameterName = "@Id";
        paramId.Value = employee.ID;
        cmd.Parameters.Add(paramId);

        SqlParameter paramName = new SqlParameter();
        paramName.ParameterName = "@Name";
        paramName.Value = employee.Name;
        cmd.Parameters.Add(paramName);

        SqlParameter paramGender = new SqlParameter();
        paramGender.ParameterName = "@Gender";
        paramGender.Value = employee.Gender;
        cmd.Parameters.Add(paramGender);

        SqlParameter paramCity = new SqlParameter();
        paramCity.ParameterName = "@City";
        paramCity.Value = employee.City;
        cmd.Parameters.Add(paramCity);

        SqlParameter paramSalary = new SqlParameter();
        paramSalary.ParameterName = "@Salary";
        paramSalary.Value = employee.Salary;
        cmd.Parameters.Add(paramSalary);

        SqlParameter paramDateOfBirth = new SqlParameter();
        paramDateOfBirth.ParameterName = "@DateOfBirth";
        paramDateOfBirth.Value = employee.DateOfBirth;
        cmd.Parameters.Add(paramDateOfBirth);

        con.Open();
        cmd.ExecuteNonQuery();
    }
}

Creating the Edit Post Method:

Please copy and paste the following “Edit” (HttpPost) action method in “EmployeeController“.

[HttpPost]
public ActionResult Edit(Employee employee)
{
    if (ModelState.IsValid)
    {
        EmployeeBusinessLayer employeeBusinessLayer = new EmployeeBusinessLayer();
        employeeBusinessLayer.UpdateEmmployee(employee);
        return RedirectToAction("Index");
    }
    return View(employee);
}

Code Explanation:

1. The above Edit action method is decorated with the [HttpPost] attribute. So this method only responds to HTTP post requests when updating data.
2. This method receives the modified “Employee” object as a parameter. This object is then passed to UpdateEmmployee() method which updates the employee details. After the employee details are saved the user is redirected to “Index” action.
3. If there are model validation errors none of the code in the IF block gets executed. In this case, the user stays on the “Edit” view. Since we are passing the “Employee” object to the “Edit” view the user gets to see the validation errors. This allows him to fix those errors and re-submit the view.

In the next article, I am going to discuss how unintended updates can happen in ASP.NET MVC and how to prevent unintended updates in ASP.NET MVC Application. Here, in this article, I try to explain how to update the Model in ASP.NET MVC application with an example. I hope this article will help you with your needs. I would like to have your feedback. Please post your feedback, question, or comments about this article