database views are updatable from model?

See more:

MVC

database view

CREATE view [dbo].[VsEFS] with schemabinding as
(
      select EfId ,EfAMaxMarks,EfCent,EfRollNo ,A.FsAdded ,A.FsMarks ,A.FsEfId,A.FsEsId
      from [dbo].ExamForms ,[dbo].FormSub A
       where EfId=FsEfId
 )
GO

CREATE UNIQUE CLUSTERED INDEX [IX_O] ON [dbo].[VsEFS] 
(
	[EfId] ASC,
	[FsEsId] ASC
)
WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
GO

In Controller I have written a code to update value of FsAdded :

IEnumerable<VsEF> vs = db.VsEFS.Where(c => c.EfId == 16714);
foreach (var t in vs)
           {
               if (t.FsEsId==5491)
               t.FsAdded = "45";
           } 

 db.SaveChanges();

but while updating values in database it gives an error like:
The property 'FsAdded' is part of the object's key information and cannot be modified.

database views are updatable from model?
any one can help?