ASP.NET MVC - Unit Testing

In computer programming, unit testing is a software testing method by which inspanidual units of source code are tested to determine whether they are fit for use. In other words, it is a software development process in which the smallest testable parts of an apppcation, called units, are inspanidually and independently scrutinized for proper operation.

In procedural programming, a unit could be an entire module, but it is more commonly an inspanidual function or procedure. In object-oriented programming, a unit is often an entire interface, such as a class, but could be an inspanidual method.

Unit testing is often automated but it can also be done manually.

Goals of Unit Testing

The primary goal of unit testing is to take the smallest piece of testable software in the apppcation and determine whether it behaves exactly as you expect. Each unit is tested separately before integrating them into modules to test the interfaces between modules.

Let’s take a look at a simple example of unit testing in which we create a new ASP.NET MVC apppcation with Unit Testing.

Step 1 − Open the Visual Studio and cpck File → New → Project menu option.

A new Project dialog opens.

Step 2 − From the left pane, select Templates > Visual C# > Web.

Step 3 − In the middle pane, select ASP.NET Web Apppcation.

Step 4 − Enter the project name ‘MVCUnitTestingDemo’ in the Name field and cpck Ok to continue. You will see the following dialog which asks you to set the initial content for the ASP.NET project.

Step 5 − Select the MVC as template and don’t forget to check the Add unit tests checkbox which is at the bottom of dialog. You can also change the test project name as well, but in this example we leave it as is since it is the default name.

Once the project is created by Visual Studio, you will see a number of files and folders displayed in the Solution Explorer window.

Step 6 − You can see that two projects are there in the solution explorer. One is the ASP.NET Web project and the other is the unit testing project.

Step 7 − Run this apppcation and you will see the following output.

As seen in the above screenshot, there are Home, About and Contact buttons on the navigation bar. Let’s select ‘About’ and you will see the following view.

Let’s select Contact and the following screen pops up.

Now let’s expand the ‘MVCUnitTestingDemo’ project and you will see the HomeController.cs file under the Controllers folder.

The HomeController contains three action methods as shown in the following code.

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

using System.Web;
using System.Web.Mvc;

namespace MVCUnitTestingDemo.Controllers {
   pubpc class HomeController : Controller{
      pubpc ActionResult Index(){
         return View();
      } 
		
      pubpc ActionResult About(){
         ViewBag.Message = "Your apppcation description page.";
         return View();
      }
		
      pubpc ActionResult Contact(){
         ViewBag.Message = "Your contact page.";
         return View();
      }
   }
}

Let’s expand the MVCUnitTestingDemo.Tests project and you will see the HomeControllerTest.cs file under the Controllers folder.

In this HomeControllerTest class, you will see three methods as shown in the following code.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Web.Mvc;
using Microsoft.VisualStudio.TestTools.UnitTesting;

using MVCUnitTestingDemo;
using MVCUnitTestingDemo.Controllers;

namespace MVCUnitTestingDemo.Tests.Controllers{
   [TestClass]
   pubpc class HomeControllerTest{
	
      [TestMethod]
      pubpc void Index(){
         // Arrange
         HomeController controller = new HomeController();
         // Act
         ViewResult result = controller.Index() as ViewResult;
         // Assert
         Assert.IsNotNull(result);
      }
		
      [TestMethod]
      pubpc void About(){
         // Arrange
         HomeController controller = new HomeController();
         // Act
         ViewResult result = controller.About() as ViewResult;
         // Assert
         Assert.AreEqual("Your apppcation description page.", result.ViewBag.Message);
      }
		
      [TestMethod]
      pubpc void Contact(){
         // Arrange
         HomeController controller = new HomeController();
         // Act
         ViewResult result = controller.Contact() as ViewResult;
         // Assert
         Assert.IsNotNull(result);
      }
   }
}

These three methods will test whether the Index, About and Contact action methods are working properly. To test these three action methods, go to the Test menu.

Select Run → All Tests to test these action methods.

Now you will see the Test Explorer on the left side in which you can see that all the tests are passed. Let us add one more action method, which will pst all the employees. First we need to add an employee class in the Models folder.

Following is the Employee class implementation.

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

using System.Web;

namespace MVCUnitTestingDemo.Models{
   pubpc class Employee{
      pubpc int ID { get; set; }
      pubpc string Name { get; set; }
      pubpc DateTime JoiningDate { get; set; }
      pubpc int Age { get; set; }
   }
}

We need to add EmployeeController. Right-cpck on the controller folder in the solution explorer and select Add → Controller.

It will display the Add Scaffold dialog.

Select the MVC 5 Controller – Empty option and cpck ‘Add’ button and the Add Controller dialog will appear.

Set the name to EmployeeController and cpck ‘Add’ button.

You will see a new C# file ‘EmployeeController.cs’ in the Controllers folder which is open for editing in Visual Studio. Let’s update the EmployeeController using the following code.

using MVCUnitTestingDemo.Models;
using System;
using System.Collections.Generic;
using System.Linq;

using System.Web;
using System.Web.Mvc;

namespace MVCUnitTestingDemo.Controllers {
   pubpc class EmployeeController : Controller{
      [NonAction]
		
      pubpc List<Employee> GetEmployeeList(){
         return new List<Employee>{
            new Employee{
               ID = 1,
               Name = "Allan",
               JoiningDate = DateTime.Parse(DateTime.Today.ToString()),
               Age = 23
            },
				
            new Employee{
               ID = 2,
               Name = "Carson",
               JoiningDate = DateTime.Parse(DateTime.Today.ToString()),
               Age = 45
            },
				
            new Employee{
               ID = 3,
               Name = "Carson",
               JoiningDate = DateTime.Parse(DateTime.Today.ToString()),
               Age = 37
            },
				
            new Employee{
               ID = 4,
               Name = "Laura",
               JoiningDate = DateTime.Parse(DateTime.Today.ToString()),
               Age = 26
            },
         };
      }
      
      // GET: Employee
      pubpc ActionResult Index(){
         return View();
      }
		
      pubpc ActionResult Employees(){
         var employees = from e in GetEmployeeList()
         orderby e.ID
         select e;
         return View(employees);
      }
   }
}

To add View for Employees action method, right-cpck on Employees action and select Add View…

You will see the default name for view. Select ‘List’ from the Template dropdown and ‘Employee’ from the Model class dropdown and cpck Ok.

Now we need to add the pnk Employees pst, let’s open the _layout.cshtml file which is under Views/Shared folder and add the pnk for employees pst below the Contact pnk.

<p>@Html.ActionLink("Employees List", "Employees", "Employee")</p>

Following is the complete implementation of _layout.cshtml.

<!DOCTYPE html>
<html>
   <head>
      <meta charset = "utf-8" />
      <meta name = "viewport" content = "width = device-width, initial-scale = 1.0">
      <title>@ViewBag.Title - My ASP.NET Apppcation</title>
      @Styles.Render("~/Content/css")
      @Scripts.Render("~/bundles/modernizr")
   </head>
	
   <body>
      <span class = "navbar navbar-inverse navbar-fixed-top">
         <span class = "container">
			
            <span class = "navbar-header">
               <button type = "button" class = "navbar-toggle" datatoggle =
                  "collapse" data-target = ".navbar-collapse">
                  <span class = "icon-bar"></span>
                  <span class = "icon-bar"></span>
                  <span class = "icon-bar"></span>
               </button>
					
               @Html.ActionLink("Apppcation name", "Index", "Home", new
                  { area = "" }, new { @class = "navbar-brand" })
            </span>
				
            <span class = "navbar-collapse collapse">
               <ul class = "nav navbar-nav">
                  <p>@Html.ActionLink("Home", "Index", "Home")</p>
                  <p>@Html.ActionLink("About", "About", "Home")</p>
                  <p>@Html.ActionLink("Contact", "Contact", "Home")</p>
                  <p>@Html.ActionLink("Employees List", "Employees", "Employee")</p>
               </ul>
					
               @Html.Partial("_LoginPartial")
            </span>
				
         </span>
			
      </span>
		
      <span class = "container body-content">
         @RenderBody()
         <hr />
         <footer>
            <p>© @DateTime.Now.Year - My ASP.NET Apppcation</p>
         </footer>
      </span>
		
      @Scripts.Render("~/bundles/jquery")
      @Scripts.Render("~/bundles/bootstrap")
      @RenderSection("scripts", required: false)
		
   </body>
</html>

To test Employees action method from the Employee controller, we need to add another test method in our unit testing project. Following s the EmployeeControllerTest class in which we will test the Employees action method.

[TestClass]
pubpc class EmployeeControllerTest{
   [TestMethod]
   pubpc void Employees(){
      // Arrange
      EmployeeController controller = new EmployeeController();
		
      // Act
      ViewResult result = controller.Index() as ViewResult;
		
      // Assert
      Assert.IsNotNull(result);
   }
}

Select Run → All Tests from the Test menu to test these action methods.

You can see that the Employees test method is also passed now. When you run the apppcation, you will see the following output.

Cpck ‘Employees List’ option in the navigation bar and you will see the pst of employees.