.net - Get A Difference Of Pending Changes To A Model In MVC 2?
Mar 26, 2011
I am working on an ASP.Net MVC app and I want to show a confirmation page after the user edits some data. What I would like to show is a list of the pending changes that the user made to the model. For example, want to make the following changes:
FieldName:
Previous Value: XXX
New Value: YYY
I know I can read my stored value from the database and compare it with the POSTed object but I want this to work generally. What would be some good ways to approach this?
To clarify, I am looking for a general way to get a "diff" of the pending changes. I already know how to get the previous and pending changes. Kind of like how TryUpdateModel() can attempt to update any Model with posted values. I'd like a magical GetPendingModelChanges() method that can return a list of something like new PendingChange { Original = "XXX", NewValue = "YYY"} objects.
I'm building an MVC 2 RTM app, and I want to be able to share my model across applications. I'd *like* to be able to implement it like:ASP.NET MVC2 app (holds Views and Controllers)Class library to hold Model(s)WCF app to handle the data transactions with the models via different data stores across apps I had the MVC app working fine, but I wanted to abstract the data stuff and be able to work with the model across apps through the WCF site, so I created a class library project and moved all of the Models classes into that and set-up a WCF app, then added project references to the MVC and WCF apps that point at the class library. The idea was I can create services that take and return objects from the model via method calls across apps. It appears that everything's wired up correctly in the MVC project, so I'm passing the objects stored in the Models class library between controllers and views and everythig is compiling just fine, but for some reason the data is not being passed back from the views to the controller on POST -- all of the properties in the classes are null or empty.
When I debug the app, I can see that the values are stored in the model data dictionary but not the model object itself. What am I doing wrong? Am I on the wrong path, or missing something obvious (to some)?
I made a few changes to the DB in SQL server management studio then right clicked on the .edmx doc to get it to update. That seemed to work fine but when i compiled the app everything that referenced the EF seems to be broken.The Error list now contains the below error for all classes that used it.
The type or namespace name '' could not be found (are you missing a using directive or an assembly reference?)
I have an issue of static variable in an asp.net application. Let's say I have a server with 8 CPUs running windows 2008 R2 hosting an asp.net webbsite, nothing fancy here, no funny configuration.
Is the following statement true? at any single time, there's one and only one process is running and accepting requests, even in the recycling stage. The reason I am asking is: I have a static field in my class, and I want to make that's the only static instance in the website. I've heard in some circumstances, IIS is recylcing your application, and it will start a new process, but the old process is still working, thus I will have 2 static instances in memory, which defeat the purpose of static field.
One step further, let's assume there might be 2 instances in memory, can I assume there are at most 2 instances at any single time? And can I assume once the second instance is up, the first instance will NEVER accept new requests?
Another question: Recently I have a problem with an applicationdomain concept. Looks like if an application domain causes a memory leak, unload the domain will not release the memory (Umanaged leak). So to what extent Application Domain is isolated?
I am trying to make a post that should use the Default Model Binder functionality in ASP.NET MVC 2 but unfortunately I can't get through. When I click on the checkout button I populate a form dinamically using jQuery code and then submit this form to the server. This is the form that get submitted
This is the jQuery code that handle the submit event for the form $("#cartForm").submit(function (event) { event.preventDefault(); var form = $("#cartForm"); var panel = form.parent(); panel.parent().block(); $.ajax({ type: "post", dataType: "html", url: '<%: Url.Content("~/Order/Checkout") %>', async: false, data: form.serialize(), success: function (response, status, xml) { panel.parent().unblock(); }, error: function (response) { panel.parent().unblock(); } }); });
This is the controller action that should be get called [HttpPost] [ValidateAntiForgeryToken] public virtual ActionResult Checkout( CartModel cart ) { } And finally this is the CartModel class involved public class CartModel : BaseModel{ public int CustomerID { get; set; } public int FirmID { get; set; } public List<CartItemModel> CartItems { get; set; } public CartModel() { CartItems = new List<CartItemModel>(); } } public class CartItemModel : BaseModel { public int ServiceTypeID { get; set; } public int Quantity { get; set; } }
But the default Model Binder does not bind the web form data to a CartModel class. Using Fiddler I have been able to see that the data sent to the server is correct as you can see from the following snapshot.
when I use Html.HiddenFor( model => model.OwnerId ) to create a hidden field, the value assigned to that field is zero. When I use <input type="hidden" value="<%: Model.OwnerId %>" /> to add the hidden field to the form, the value is assigned correctly.
Why would Html.HiddenFor( model => model.OwnerId ) not get the correct value from the Model object? Am I supposed to load model state somehow separate from returning the model object from the action method? Here is the view:
[Code]....
The Create action method is relatively straight forward.
I've been used to decorating data model classes with data annotation attributes, but the purist in me baulks slightly at including purely presentational attributes such as display format here. I am, however, quite happy to keep validation centric attributes here. One good reason I have to continue keeping all annotations etc. in the data model is that my view model aggregates data model classes, e.g.
my ViewModelBase.DetailItem<TEntity> property in the view model is just a reference to an entity class in my data model. If I wanted to move presentational annotations to the view model, I would have to quite radically revise my design to one where I duplicate data model properties in my view model and use an object mapping tool to populate view model objects based on data model objects.
Say I got a domain model as follows: (and my repository expect an instance of this object)
[Code]....
And a view model (which my views are based on)
[Code]....
At the moment I got it like this and have my controller action manually create a new Person object from the PersonModel object before passing it on to the repository, which does not feel right.
So I tried to have PersonModel inherit from Person and pass that to the repository (also tried casting the PersonModel to a Person object first), but that don't work out.
What's the right way to have PersonModel automatically cast to Person? I want to keep this logic as my current structure allow me to keep things really loosely coupled, with the repository layer not having a clue how it's being used.
I have recently started working on ASP.NET with MVC 2 framework, and I am facing following difficulty in validating my data,
Scenario:
In my application the view (ASPX) is divided into tabs (jQuery) and each tab's content is ViewUserControl (ASCX). The main model for the view has collection of sub models for individual tabs. I use RenderPartial method to render view user control.
[Code]....
And the user control (Tab1.ascx) refers the specific model for it,
[Code]....
Now if in my Tab1Model if I put following validation
[Code]....
In the controller ModelState.IsValid is always indicates TRUE. How do I override the validation behavior such that it as well looks the items in the collection member (which holds sub models) as well.
I am a newbie in mvc3 and i'm wondering how to use attribute like [Display(Name="")] for model that comes from an entity data model that I provide im my "Model" folder in my mvc3 project.
I didn't provide a .cs class for each of my database tables .
other words, I want the controller class render a edit form for me like :
I want to authenticate a user using model popup extender. So I wrote a program to do this. Everything OK when user enter the correct details. But user enters the wrong detail, it should shows in a lablel in a popup panel. It shows; but the problem is it close the popup . But I want to keep the popup if the user enters the wrong details. How can I do this?
I thought that <%: had replaced <%=, since mentions on [URL]Prior to ASP.NET 4, the <%= %> syntax was used to execute code and write it out to the page. Starting with ASP.NET 4, you should always use the <%: %> syntax instead..."
I hope this isn't too much of a newbie question. I seem to always use the correct syntax, but I don't really understand why I'm using the <%: and <%= in ASP.NET, and I was hoping someone could clarify for me. I found this article which explains <%= and <%#, but wasn't able to find anything in Google on <%:.
What is the difference between c#.net and vb.net ?
I faced this question in an interview. Any technical difference is there ? I heard that there are two methods additional in vb.net which are not there in vb.net.
I am in the process of learning MVC, and thought I would parallel the work in both C# and VB.NET. I ran into a snag when right-clicking in an action method inside of a controller to add a view - in C# if I choose to strongly type the view it includes all the objects in the models folder in the drop-down list for selection; however, in VB.NET none of the models are available in the list. Is there some step I need to take in order to make the models objects available in the drop down for selection?
I need to get model data into a JavaScript variable and use it as an int to compare values. But I can only figure out how to get the model data as strings, otherwise the compiler complains.
So how can I get the max and taskBudgetHours as int variables in the Javascript?
