I set a session object at one juncture in my code:
Session("my_name") = "Dave"
Later in my code I give the user a chance to update this object:
Session("my_name") = TextBox1.Text
I reload my page and display a little hello statement like this:
Label1.Text = "Hello" & CStr(Session("my_name"))
The result is: "Hello Dave" no matter what I change Session("my_name") too.
EDIT: Here is the a full code-behind I wrote up to demonstrated:
Public Class WebForm1
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Response.Cache.SetCacheability(HttpCacheability.NoCache)
Response.ExpiresAbsolute = DateTime.Now.AddMonths(-1)
If Page.IsPostBack = False Then
Session("my_name") = "Dave"
End If
Label1.Text = CStr(Session("my_name"))
End Sub
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
Session("my_name") = TextBox1.Text
End Sub
Lets say I am doing a shoping cart. I authenticate the user with a session variable.For example:
If(Request.IsAuthenticated) // Here I want to add to the shoping cart. // Can I do the following Session["Cart"] = "Washing Machine"; Now will this Session["Cart"] value which is washing machine here be unique to diff customers?
I have a view that is based on a view model. This model has a single property called Entity, of type ServiceProvider, which is a Linq2SQL object. This object has relationships to 2 other objects Address and ServiceProviderGroup. In a HTML view I have textboxes that allow the properties of the Entity property to be changed and also the properties of the Address object related to it.
E.g: ViewModel.Entity.Code, ViewModel.Entity.Name, ViewModel.Entity.Address.City, etc, etc.
There is also a selectlist that will allow the Entity.GroupId (int) property to be changed. This defines a relationship to the ServiceProviderGroup class which is also accessible via a Group propery. (standard linq2sql back references)
The Edit[Post] method accepts an instance of this view model and all properties (on the Entity, Entity.Address properties) are set as expected. I then lookup the original object in the database and I also bring back the original address and group data.
E.G: entity => entity.Code == viewModel.Code && entity.Address.Id == viewModel.Address.Id && entity.Group.Id == viewModel.Entity.GroupId (I'm not looking at the code, but it's something similar to this)
Either way the original Entity, Entity.Address, etc, come back from the database. I then apply the changes from the view model to the original object using UpdateModel and everything is updated as expected. But, if I try to change Entity.GroupId, i.e. change the relationship on the entity to another ServiceGroupProvider object, I get an exception in the generated code of the ServiceProvider object.
This happens in the GroupId property of the ServiceProvider class (viewModel.Entity). When it reaches the line if(!this.HasLoadedOrAssignedValue) it enters the "if" statement and throws an exception. When the data is first read from the database it skips this part. But, when UpdateModel attempts to apply the new Entity.GroupId value it throws the exception.
I found some code on the web and it threw me off. Look at the code below. You will notice only when the Hits == 1, does the cache get added. After that, the cache object isn't updated. It begs the question, does the object when updated, update the cache as well automatically? The answer here would make me remove some code in some of my classes.
I am looking for an accepted pattern for using MVC 2 and EF. Especially I am interested on how to implement updates. Where should the ObjectContext be created, where should the queries be, how to pass a model object from the controller and have it persisted with minimum robust code. I also want to be able to use transactions when updating multiple objects.
I used Linq in an asp.net application (code behind model). With EF I was hearing it was much more n-tier friendly, but I don't find it any different, rather than people talking about POCO which to me, all it means is satisfying the desire of those that want to have control of every piece of code being created.
I have a question, much liket this unanswered one. I'm trying to work with the entity framework, and having a tough time getting my foreign tables to update. I have something basically like this in the DB:
Incident (table):
-ID -other fields
Responses (table):
-FK:Incident.ID -other fields
And and entities that match:
Incident (entity) -ID -Other fields -Responses (EntityCollection of Responses via navigation property)
Each Incident can have 0 or more responses.
In my Webpage, I have a form to allow the user to enter all the details of an Incident, including a list of responses. I can add everything to the database when a new Incident is created, however I'm having difficulty with editing the Incident.
When the page loads for edit, I populate the form and then store the responses in the viewstate. When the user changes the list of responses (adds one, deletes one or edits one). I store this back into the viewstate. Then when the user clicks the save button, I'd like to save the changes to the Incident and the Responses back to the DB. I cannot figure out how to get the responses from the detached viewstate into the Incident object so that they can be updated together.
Currently when the user clicks save, I'm getting the Incident to edit from the db, making changes to the Incident's fields and then saving it back to the DB. However I can't figure out how to have the detached list of responses from the viewstate attach to the Incident. I have tried the following without success:
Clearning the Incident.Responses collection and adding the ones from the viewstate back in:
Incident.Responses.Clear() for each objResponse in Viewstate("Responses") Incident.Responses.add(objResponse) next Creating an EntityCollection from my list and then assiging that to the Incident.Responses Incident.Responses = EntityCollectionFromViewstateList Iterating through the responses in Incident.Response and assigning the corresponding object from viewstate: for each ObjResponse in Incident.Responses objResponse = objCorrespondingModifedResonseFromViewState Next
These all fail, I'd like to be able to merge the changes into the Inicdent object so that when the BLL calls SaveChanges on the changes to both the Incident and Responses will happen at the same time.
I have inherited a very large ASP.NET app that needs to be modified to use a State Server instead of in-proc sessions. I need to track down all classes used in session throughout the app and then determine if they can be serialized. Are there any tools that can be used to analyze the code to determine the classes used in session?
In the project I'm working on I have got a list List<Item> with objects that Is saved in a session. Session.Add("SessionName", List);
In the Controller I build a viewModel with the data from this session
[Code]....
and in my View I loop trough the list of Items and make a form for all of them to be able to remove the item.
[Code]....
When the post from the submit button is handeld the item is removed from the array and post back exactly the same viewModel (with 1 item less in the itemList).
return View("view.ascx", viewModel);
When the post is handled and the view has reloaded the value's of the html.Hidden and Html.Textbox are the value's of the removed item. The value of the html.Encode is the correct value. When i reload the page the correct values are in the fields. Both times i build the viewModel the exact same way.
I am getting a serialization error trying to use Session State Server instead of InProd. However, I can't figure out what is causing the error in session. I was given some code to add to the page to loop through the session object and figure out if each item in it is serializable. My problem is I don't know where to place the code in the ASP.NET page. In tracing through the code, the error just appears after steping through objects outside of the page and not when setting session. There must be some place that I can place the code on the page that is after all session objects are set but before the page will error. Where would that be?
I know that Session is for a single user , and application is for multi user purpose.The Data in the application object is shared. Right? Then how can access the application data from an another client.
If I have not activity in browser for about 10 mins, shouldn't the Session object be removed. But after 10 mins I can still access the Session variable. Am I missing something here?
EDIT:
If I access a session variable after 10 mins as shown below shouldn't I get NULL
var myObj = Session["MyKey"] as MyClass; mObj is not NULL after 10 mins.
I am developing a website where the user enters data into a form. The user can then go back and edit the data that is saved in a session variable and then the data is resaved in that session variable in an arraylist. However, for some reason although the data is resaving it is resaving the original data. I know this as I tested the code without the remove request to the arraylist and the original data was just added to the bottom of the array. I wondering if anyone would know why the new data is not saving. Any help would be really appreciated as I have only been programming for a few of months. Some of the code is below.//The gridview shown on a page which lists the objects saved by the user which he/she can edit and edit is the only one I am concerned with here as the other works
I've just upgraded my development machine from XP SP3 (IIS5.1) to Win7 x64 (IIS7.5)
Since doing this, my app has started to behave differently. Within it I store users' preferences/access levels using an instance of a class that I store within the Session object. This class is shown:
[Code]....
My requirement is that on each page request (other than the login page), the application should check that the Session object exists. The page data is therefore shown based on the values within the session object (e.g. which customer account they are using etc)...Previously on IIS5.1 if I was logged into the app, but made some changes to a file within App_Code, or Web.Config for example, when I then continued to use the app, I would get kicked out to the login page straight away. This is the intended behaviour. Now however, on IIS7.5, the app continues to provide access to the pages, but debugging shows that the session value has had all of its values set to 0 (zero). Therefore, the pages continue to load but the data shown is corrupted because the app no longer displays it accurately. Here is the code I use which (on IIS5.1) caught this occurence. Can anyone offer any advice on just what's now happening
I've noticed that once I've instantiated 3-4 objects now, my ASPX page is running slower. The response from the server (which is my own PC) is taking longer.
With one or two objects, the performance is same. After I instantiate 3, it slows a little, and 4 just completely wears it down.
I've read this article: [URL]
that says to avoid using session variables especially storing objects into them. Well thats exactly what I'm doing. My object has about 10 methods(~30 lines of code each) and 20 fields.
My question is, if I want to persist object in memory for each user session, how else could I store them on each postback if not in the session variable>? I can't use application variable because thats shared and not thread safe.
How do you work-around the fact that sessions are dropped every time you deploy certain code files to an ASP.NET website? Sometimes we need to deploy a crucial fix in the middle of the day but don't want to boot off all our users for it.
I have a dropdown list with sessions: Summer, fall, spring, summer Interim.
And also have a gridview to display hours of those sessions. When chose session from dropdown it displays the data related to gridview.
Gridview has the 'Edit' option to edit hours for each sessions:
[Code]....
When I edit let say spring and update the field it redirects me to main page but everytime it selects the data from summer).
What I want is? If choose Fall from dropdown and make edit(in editpage.aspx?id=..) and update the data, then it should redirect to main page but choose the Fall from the dropdown (Not summer)
have some Objects, lets say Employee and Role defined as below and I have defined relationships in my database that gives me a list of objects say employees and thanks to my framework each employee object also has a Role object linked via the RoleIDID, UserName, Password, Email, RoleIDRoleID, RoleNameSo in code I can do something like this
I know how to bind a simple objects to a dropdown list. However I am having problems binding my objects which contains sub objects to the control.i.e. with simple object i just do ddl.DataValueField = "myproperty" with my objects they contains sub objects which i want to bind. I have tried ddl.DataValueField = "sub-object.myproperty" which doesnt work.
firstly a static class only ever exists once and is not an instance. Any static members (ie static int NoOfPeople;) is stored in one place and is shared between all sessions (like the old global variables). Now static methods is where i'm not 100% sure. If I have a static method that doesn't use any other static members could this cause inconstant results, example (this is a fairly pointless method but just a quick example of the top of my head)
[Code]....
So in this example if two sessions (or threads) were to call this at the same time - would they both get back the expected results, because the method only uses private data (a, b and totalToReturn).Im sure this sounds a little simple but I will be using static methods to build user objects and various other objects that there will have to be a 100% garentee that the objects will not get mixed up between sessions and the wrong things return to the user.
