ViewData vs ViewBag vs TempData vs Session

In MVC there are three ways - ViewData, ViewBag and TempData to pass data from controller to view . We can also use Session to persist data during a user session.


ViewData
  • ViewData is a dictionary object that is derived from ViewDataDictionary class.
     public ViewDataDictionary ViewData { get; set; }
  • ViewData is a property of ControllerBase class.
  • ViewData is used to pass data from controller to corresponding view.
  • It’s life lies only during the current request.
  • If redirection occurs then it’s value becomes null.
  • It’s required typecasting for getting data and check for null values to avoid error.


ViewBag
  • ViewBag is a dynamic property that takes advantage of the new dynamic features in C# 4.0.
  • Basically it is a wrapper around the ViewData and also used to pass data from controller to corresponding view.
     public Object ViewBag { get; }
  • ViewBag is a property of ControllerBase class.
  • It’s life also lies only during the current request.
  • If redirection occurs then it’s value becomes null.
  • It doesn’t required typecasting for getting data.


TempData
  • TempData is a dictionary object that is derived from TempDataDictionary class and stored in short lives session.
  • public TempDataDictionary TempData { get; set; }
  • TempData is a property of ControllerBase class.
  • TempData is used to pass data from current request to subsequent request (means redirecting from one page to another).
  • It’s life is very short and lies only till the target view is fully loaded.
  • It’s required typecasting for getting data and check for null values to avoid error.
  • It is used to store only one time messages like error messages, validation messages. 
Session


  • Session is an object that is derived from HttpSessionState class.
         public HttpSessionState Session { get; }
  • Session is a property of HttpContext class.
  • Session is also used to pass data within the ASP.NET MVC application and Unlike TempData, it never expires.
  • Session is valid for all requests, not for a single redirect.
  • It’s also required typecasting for getting data and check for null values to avoid error.

Comments

Post a Comment

Popular posts from this blog

How to retain the data annotations or class during modify a table in the database

Image
In database-first approach since there is an existing database., The entity classes are automatically created by edmx model.: If we use [MetadataType(typeof(ConceptMetadataSource))] to attach a MetadataSource file which contains all the data annotations like [HiddenInput(DisplayValue = false)] or [Display(Name = "Title")]. The data annotations will be wiped out each time the entity classes are regenerated as the code will be regenerated once we modify a table in the database Solution: All you have to do is create another partial class and use Metadatatype attribute Create a metadata class in models as below…   Create a Partial class for the metadata in models as below… The new partial class can be created in a different folder
Read more

Interview Questions

Difference between GET and POST. Which one is more secure? GET and POST methods are used for the data transfer between the web pages. GET mainly used for small data which is not secure because in case of GET method, the data which we are passing will be visible in the url so we can't keep the secure data which will be visible in the url. There is also limited data which can be passed in case of GET method (max 255 character). POST is used for transferring the huge data between the pages where we can keep the secure data and can transfer it. In case of using the POST method, the data which is transferring between the pages will not be visible so it is more secure than the GET method. Also there is no limit for POST method to post the data to the next page. POST is more secure What are Razor engines? How is it diff from ASP Engines? A. RAZOR engine is the new concept in the MVC 3 which is mainly used to create the views in the MVC applications. It created the cshtml pages for...
Read more

AJAX CONTROL

Image
1.        Goto  web confiq add following controls        < controls >   < add tagPrefix = " ccl " namespace = " AjaxContolToolkit " assembly   = " AjaxContolToolkit " />      </ controls > 2.        Go to  bin folder  ->  include project -> add ajax.dll file from AjaxControl Toolkit 3.        Add  toolsciptmanager  to default.aspx            < asp : ToolkitScriptManager ID ="ToolkitScriptManager1" runat ="server">         </ asp : ToolkitScriptManager > 4.        Create a function < script type = "text/javascript" >     function panelclick()     {    alert( "click" );  ...
Read more