.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
Sign In
Win Surprise Gifts!!!

Top 5 Contributors of the Month
Gaurav Pal
Post New Web Links

ViewState and LINQ to SQL objects

Posted By:      Posted Date: October 13, 2010    Points: 0   Category :ASP.Net

I'm getting the following error: "Type 'System.Data.Linq.ChangeTracker+StandardChangeTracker' in Assembly 'System.Data.Linq, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089' is not marked as serializable."

Basically, I have a LINQ entity class built from LINQ to SQL called City, which implements INotifyPropertyChanging and INotifyPropertyChanged that I'm trying to store in ViewStateWhen I remove these interfaces from the class, the error goes away.  When left on, the error is there.

I know that these interfaces are what enable the DataContext object's to track changes and persist those changes to the database using the dc.SubmitChanges() method.  Is there anything that I need to do to be able to enable storing a LINQ to SQL object in ViewState?  I thought I read that this was possible, and that Asp.net allowed persisting changes like that across post-backs.


View Complete Post

More Related Resource Links

Using Linq to Objects within an ASP.Net application

I am thinking to continue the LINQ series of posts but I want to give a clear example on Linq to Objects . In all my classes people seem to have the following answer to this question, " What kind of data can we query with LINQ? " Most people say " Well, we can query an SQL server database " . I am not very pleased when people forget the other flavors. LINQ to Objects allow us to write "queries" over collections of objects.This is the first and most basic flavor of LINQ. LINQ to Objects enables you...(read more)

creating dataset using list of objects in Linq



 I am using Linq To Sql to get List of objects with data from database. To bind data with a grid view i am creating a dataset explicitly and then adding List values to that explicitly created dataset.

Now my question is whether it is a good pratice to do what i am doing (in terms of resource utilization) or is there any better way to this...

Playing with Linq grouping: GroupByMany?

One of its features is grouping. Many people understand grouping like it is defined in Sql. Linq is implementing grouping quite the same way. Let's discover this syntax and how to make consecutive groups easier.

LINQ : Implementing IN and NOT IN

I got tried of typing

var result = from s in source
where items.Contains(s)
select s;and so I implemented the IN and NOT IN methods as extension methods:

101 LINQ Samples Tutorials

101 LINQ Example with sample code snippets....This sample prints each element of an input integer array whose value is less than 5. The sample uses a query expression to create a new sequence of integers and then iterates over each element in the sequence, printing its value

Linq: how to share parameters between lambda expressions ?

When using Linq to objects, you will quickly feel the need to pass some parameters from a method to another but it's not so easy because each Linq method is not calling the following one. In a Linq sequence, each method is using the result computed by the previous one. So, local contexts are not visible from one method to another.
The compiler is using two technical different ways to let parameters go out of a method.

Linq to Sql CompiledQuery container

Ok now let's go. Here is just a little trick but with some interesting patterns that could be useful in some other contexts not connected to Linq to Sql.

When using Linq expressions, like with Linq to Sql, translating the expression into something else (sql for example) is taking time and resources. Sometimes it's negligible, sometimes not...

LINQ to SQL Paging using GridView in C# and ASP.NET 3.5

This tutorial will show you how we can extend the LINQ to SQL Class and create methods that will allow us to page data from a SQL database. C# version.

What is Lambda Expressions In LINQ

A lambda expression is an anonymous function that can contain expressions and statements, and can be used to create delegates or expression tree types.

All lambda expressions use the lambda operator =>, which is read as "goes to". The left side of the lambda operator specifies the input parameters (if any) and the right side holds the expression or statement block. The lambda expression x => x * x is read "x goes to x times x." This expression can be assigned to a delegate type as follows:

How to create 3 tier application using LINQ

As you know that in 3 tier architecture there are three layers

User interface layer. (Is our Form in Windows application and .aspx page in Web application)
Data Access layer. (Which provides interface between Business logic layer and Database)
Business Logic layer.(Which stores your application logic)

Building a LINQ Provider

Throughout this article, we will build a simple IQueryable provider similar to the LINQ to SQL provider demonstrating what is needed to build a custom provider that is capable of executing LINQ queries and performing create, update and delete operations.

LINQ to SQL Performance Considerations

As developers we have a wide array of tools at our disposal. One of the most time consuming, but most beneficial tasks we must undertake is to determine which of those tools to use for a given situation.

Need help with objects and arrays


I have an objuct that I declared like this:

    Class DailyStats
        Dim _day As String
        Dim _hour As String
        Dim _impressions As String
        Dim _clicks As String
        Property Day() As String
                Return _day
            End Get
            Set(ByVal value As String)
                _day = value
            End Set
        End Property
        Property Hour() As String
                Return _hour

Passing Linq Statement between master and content page


I usually work with windows forms, and am just starting to work with ASP.Net, so appologies if this is a dumb question!

I have a master page which has a search button on it. The results of this are built up using a Linq statement and if there are any results, I want to display the results in a contents page.

On the masterpage, I have the following code:

Private _res

    Public Overridable ReadOnly Property SearchRes()
            Return _res
        End Get
    End Property

 Private Sub DoSearch()
   'some code to get a linq result

    If res.Any Then
            _res = res
            Server.Transfer("SearchResults.aspx", True)
            'no results
            LabelNoRes.Visible = True
        End If
 End Sub

On the SearchResults.aspx page I have this code.

Dim m As pxSite = CType(Page.Master, MasterPage)
        If m.SearchRes IsNot Nothing Then
            Label1.Text = "Results found = " & m.SearchRes.Count
        End If

m.searchRes is always nothing. 

What am I doing wrong here?


How to check for null/empty strings on dynamic objects?


What is the proper way to check for null or empty strings on dynamic objects? This is the only solution I've found so far:

if (admin.PasswordHash.GetType() == typeof(DBNull) || admin.PasswordHash == string.Empty)

If the field is null, the object returned is DBNull.Value, but if the field is empty string, it's return as a System.String object. This makes it impossible to do regular "admin.PasswordHash == DBNull.Value" check, as that will fail whenever the field has been set to empty string. Is my example the right (and only) way to go?

Linq - add data to database then email user the details


Hi all

I'm not sure how to structure the code for this but what I want to do is be able to add data to a database, and once this has completed successfully, then email the user to say the details have been added successfully to the database.

I need to:

1. Check that the relevant data has been added into the database then

2. Email the details of the relevant data when completed. 


Thanks in advance for your help,




how to serialize objects ??


Is there any way or process to serialize the the objects?? i am trying to store the instance of few control in viewstate but it shows error msg that it is not a serialized object. should i perform some steps to serialize the objects ???

ASP.NetWindows Application  .NET Framework  C#  VB.Net  ADO.Net  
Sql Server  SharePoint  Silverlight  Others  All   

Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend