ViewData in Asp.Net Mvc application

• ViewData is one of the property of ControllerBase class.
• It is described as dictionary object whichis derived from ViewDataDictionary class.Thse syntax of it is as follows:-

public ViewDataDictionary ViewData { get; set; }

• Passing and maintaing data from controller to corresponding view is done using ViewData.
• Their only aim is to provide communication between controller and corresponding view therefore ViewData life is short i.e within current request and it's value becomes null whenever redirection occur.
• Type casting for complex data type ViewData value is required.

Example of ViewData:

Controller with Index action have ViewData:-

public ActionResult Index()
{
ViewData["Name"] = "Suraj rana";
return View();
} 

ViewData is used in a view. With respect to Index action a view is called and data between them is maintained by ViewData:-

@ViewData["Name"]