Asp.Net Mvc Tempdata Viewbag Viewdata Complete Guide

Step 1: Create a New ASP.NET MVC Project

1. Open Visual Studio.
2. Go to File -> New -> Project.
3. Choose ASP.NET Web Application (.NET Framework).
4. Name the project (e.g., MVCDataExample).
5. Click OK.
6. Select MVC template.
7. Click OK.

Step 2: Model Creation

Create a simple model to work with. For example, a Student model.

1. Right-click on Models folder.
2. Add -> Class.
3. Name it Student.cs.
4. Add properties to the Student model.

namespace MVCDataExample.Models
{
    public class Student
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public int Age { get; set; }
    }
}

Step 3: Create the Controller

1. Right-click on Controllers folder.
2. Add -> Controller.
3. Select MVC 5 Controller - Empty.
4. Name it HomeController.cs.
5. Add using MVCDataExample.Models; at the top.

using MVCDataExample.Models;
using System.Web.Mvc;

namespace MVCDataExample.Controllers
{
    public class HomeController : Controller
    {
        // GET: Home
        public ActionResult Index()
        {
            return View();
        }

        public ActionResult StudentDetails()
        {
            var student = new Student { Id = 1, Name = "John Doe", Age = 20 };

            // Using ViewData
            ViewData["StudentName"] = student.Name;
            ViewData["StudentAge"] = student.Age;

            // Using ViewBag
            ViewBag.StudentNameVB = student.Name;
            ViewBag.StudentAgeVB = student.Age;

            // Using TempData
            TempData["StudentNameTD"] = student.Name;
            TempData.Keep("StudentNameTD"); // To keep the value in TempData for the next action

            return RedirectToAction("DisplayStudentData");
        }

        public ActionResult DisplayStudentData()
        {
            return View();
        }
    }
}

Step 4: Create Views

1. Right-click on Views -> Home.
2. Add -> View.
3. Name it Index.cshtml.

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>
<p>This is the Index page. Click <a href="@Url.Action("StudentDetails")">here</a> to see student details.</p>

4. Right-click on Views -> Home.
5. Add -> View.
6. Name it StudentDetails.cshtml.

@{
    ViewBag.Title = "Student Details";
}

<h2>Student Details</h2>
<p>Redirecting to DisplayStudentData...</p>

7. Right-click on Views -> Home.
8. Add -> View.
9. Name it DisplayStudentData.cshtml.

@{
    ViewBag.Title = "DisplayStudentData";
}

<h2>Display Student Data</h2>
<h3>Using ViewData:</h3>
<p>Student Name: @ViewData["StudentName"]</p>
<p>Student Age: @ViewData["StudentAge"]</p>
<h3>Using ViewBag:</h3>
<p>Student Name: @ViewBag.StudentNameVB</p>
<p>Student Age: @ViewBag.StudentAgeVB</p>
<h3>Using TempData:</h3>
<p>Student Name: @TempData["StudentNameTD"]</p>

Step 5: Run the Application

1. Press F5 or click "Start" button to run the application.
2. Navigate to the Index page.
3. Click the link to StudentDetails.
4. Check the DisplayStudentData page to see the data being passed using ViewData, ViewBag, and TempData.

Explanation:

• ViewData: A ViewDataDictionary object that derives from Dictionary<string, object>. It requires type casting for complex data types. It’s available during the current request only.

• ViewBag: A dynamic type object that provides a dynamic view of data available on the View.

• TempData: Used to pass data between controller actions. It is available for the duration of an HTTP request. It uses session state to store data in server memory.

When to use what:

• ViewData/ViewBag: Use these for data that needs to be passed within the same view or between a controller action and the corresponding view.
• TempData: Use this when you need to pass data to another action method, especially in redirection scenarios. Use TempData.Keep(key) to retain the data for the next request.