How To Use ViewData, ViewBag And TempData in MVC

Before this I would request you to go through previous articles on ASP.NET MVC

• Introduction to ASP.NET MVC
• Creating Sample MVC Application
• Passing Data from Controller to View in ASP.NET MVC ASP.NET MVC

Let us first understand what is the purpose of ViewData, ViewBag and TempData in ASP.NET MVC.

ViewData

It is a dictionary which can contain key-value pairs where each key must be string. We can use it in transferring data from Controller to View. We can only transfer data from Controller to view but if we wish to pass data back again to controller then it is not possible. So it is valid only for the current request.

ViewBag

ViewBag is also similar to ViewData. It is used to transfer data from Controller to View. It is a type of Dynamic object, that means you can add new fields to viewbag dynamically and access these fields in the View. You need to initialize the object of viewbag at the time of creating new fields.

TempData

TempData is a dictionary object derived from TempDataDictionary. It is for subsequent HTTP requests; unlike ViewBag and ViewData, those stay only for current request. It can be used to maintain data between controller actions as well as redirects.

I hope the terms seem clear now. So let us create an application and implement these to understand the usage.

Open Visual Studio. Go to File->New->Project. Give a suitable name to the application. Click OK.



Select Empty Template. Click OK.



Now our application is created. We have a very basic MVC structure in the application with primarily three folders: Model, View and Controller.

Now we will add a Controller. Right click on Controller. Add->Controller.



Select MVC 5 Empty Controller. Click Add.



We will give a suitable name to the controller. Click Add once name is assigned.



Let us write some code in the controller class.

Implementing ViewData