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  • How to read the metadata of a MKV movie files in C#?

    - by Ole Jak
    How to read the metadata of a MKV movie files in C# (or C or C++ or AS3)? for example such creator metadatacreator hasKeyframes hasVideo hasAudio hasMetaData canSeekToEnd duration datasize videosize videocodecid audiosize audiocodecid audiosamplerate audiosamplesize stereo filesize lasttimestamp lastkeyframetimestamp lastkeyframelocation keyframes (filepositions, times) width height framerate videodatarate audiodatarate

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  • Update the model on HttpPost and render the changes in the View

    - by Etienne Giust
    With MVC3, I came over that problem where I was rendering a view with an updated model at the end of an HttpPost and the changes to the model were never applied to the rendered view :   NOT working as expected ! [HttpPost]         public ActionResult Edit(JobModel editedJobModel)         {             // Update some model property             editedJobModel.IsActive = true;                          // The view will NOT be updated as expected             return View(editedJobModel);         }   This is the standard behavior. In MVC3, POSTing the model does not render the Html helpers again. In my example, a HiddenFor bound to the IsActive value will not have its value set to true after the view is rendered.   Are you stuck, then ?   Well, for one, you’re not supposed to do that: in an ideal world you are supposed to apply the Post/Redirect/Get pattern. You would redirect to a new GET after your POST performed its actions. That’s what I usually do, but sometimes, when maintaining code and implementing slight changes to a pre-existing and tested logic, one prefers to keep structural changes to a minimum.   If you really have to (but my advice is to try to implement the PRG pattern whenever possible), here is a solution to alter values of the model on a POST and have the MVC engine render it correctly :   Solution [HttpPost] public ActionResult Edit(JobModel editedJobModel) {     // NOT WORKING : Update some model property     //editedJobModel.IsActive = true;     //Force ModelState value for IsActive property     ModelState["IsActive"].Value = new ValueProviderResult(true, "True", null);          // The view will be updated as expected     return View(editedJobModel); }   As you can see, it is a “dirty” solution, as the name (as a  string) of the updated property is used as a key of the ModelState dictionary. Also, the use of ValueProviderResult is not that straightforward.   But hey, it works.

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  • Common request: export #Tabular model and data to #PowerPivot

    - by Marco Russo (SQLBI)
    I received this request in many courses, messages and also forum discussions: having an Analysis Services Tabular model, it would be nice being able to extract a correspondent PowerPivot data model. In order of priority, here are the specific feature people (including me) would like to see: Create an empty PowerPivot workbook with the same data model of a Tabular model Change the connections of the tables in the PowerPivot workbook extracting data from the Tabular data model Every table should have an EVALUATE ‘TableName’ query in DAX Apply a filter to data extracted from every table For example, you might want to extract all data for a single country or year or customer group Using the same technique of applying filter used for role based security would be nice Expose an API to automate the process of creating a PowerPivot workbook Use case: prepare one workbook for every employee containing only its data, that he can use offline Common request for salespeople who want a mini-BI tool to use in front of the customer/lead/supplier, regardless of a connection available This feature would increase the adoption of PowerPivot and Tabular (and, therefore, Business Intelligence licenses instead of Standard), and would probably raise the sales of Office 2013 / Office 365 driven by ISV, who are the companies who requests this feature more. If Microsoft would do this, it would be acceptable it only works on Office 2013. But if a third-party will do that, it will make sense (for their revenues) to cover both Excel 2010 and Excel 2013. Another important reason for this feature is that the “Offline cube” feature that you have in Excel is not available when your PivotTable is connected to a Tabular model, but it can only be used when you connect to Analysis Services Multidimensional. If you think this is an important features, you can vote this Connect item.

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  • Is a "model" branch a common practice?

    - by dukeofgaming
    I just thought it could be a good thing to have a dedicated version control branch for all database schema changes and I wanted to know if anyone else is doing the same and what have the results been. Say that you are working with: Schema model/documentation (some file where you model the database visually to generate the schema source, say MySQL Workbench, with a .mwb file, which is binary) Schema source (a .sql file) Schema-based code generation The normal way we were working was with feature branches, so we would do changes to the model files (the database specific ones), and then have to regenerate points 2 and 3, dealing with the possible conflicts (or even code rewriting). Now say that your workflow goes the same way as the previous item numbering. With a model branch you wouldn't have to reconcile the schema model with binaries in other feature branches, or have to regenerate schema source and regenerate code (which might have human code on top of it). It makes so much sense to me it feels weird not having seen this earlier as a common practice. Edit: I'm counting on branch merges to be the assertions for the model matching the code. I use a DVCS, so I don't fear long-lived branches or scary-looking merges. I'm also doing feature branching.

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  • How to Assure an Effective Data Model

    As a general rule in my opinion the effectiveness of a data model can be directly related to the accuracy and complexity of a project’s requirements. For example there is no need to work on very detailed data models when the details surrounding a specific data model have not been defined or even clarified. Developing data models when the clarity of project requirements is limited tends to introduce designed issues because the proper details to create an effective data model are not even known. One way to avoid this issue is to create data models that correspond to the complexity of the existing project requirements so that when requirements are updated then new data models can be created based any new discoveries regarding requirements on a fine grain level.  This allows for data models to be composed of general entities to be created initially when a project’s requirements are very vague and then the entities are refined as new and more substantial requirements are defined or redefined. This promotes communication amongst all stakeholders within a project as they go through the process of defining and finalizing project requirements.In addition, here are some general tips that can be applied to projects in regards to data modeling.Initially model all data generally and slowly reactor the data model as new requirements and business constraints are applied to a project.Ensure that data modelers have the proper tools and training they need to design a data model accurately.Create a common location for all project documents so that everyone will be able to review a project’s data models along with any other project documentation.All data models should follow a clear naming schema that tells readers the intended purpose for the data and how it is going to be applied within a project.

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  • Marking up table joins in the Microstrategy project metadata with the architect tool?

    - by ConcernedOfTunbridgeWells
    Hi, I am evaluating Microstrategy 9.0.1 and attempting to build a prototype metadata layer using its Architect tool. The tool doesn't seem to have any specific means to mark up joins in the way that the editing tools for SSRS data source views or Business Objects universes do. How does this work in Microstrategy - I have never used this before and may be making invalid assumptions based on other systems I have seen. If one does do this with MicroStrategy, how is it done?

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  • CakePHP: shortcomings with indirectly associated models

    - by Dan
    I'm having some issues with dealing with indirectly associated models in cakephp. My current model setup is as follows: Deliveries hasOne License License belongsTo Delivery License hasAndBelongsToMany Product (and vice-versa) License hasAndBelongsToMany ProductOption (and vice-versa) I'm trying to save information about ALL of these models inside ONE form. The shortcomings I'm running into are the following: The form helper only seems able to see the field type one level deep. saveAll() only seems able to save records one level deep (for multiple model forms). I'm searching everywhere for the solutions to these issues, but since I'm new to CakePHP, I'm not sure what the newest methods or "correct" methods are for dealing with these issues. Any advice is much appreciated. Thank you all! EDIT: I've posted code to my failed attempt here: http://bin.cakephp.org/saved/58501

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  • Best practices for model driven development using LiveCycle Data Services

    - by Adnan
    What are your advises on using model driven development in developing enterprise applications. Adobe's LiveCycle Data Services looks very promising, I have found numerous tutorials/videos that shows how fast an application can be build by having methods/functions auto-generated. What are the best-practices, is it good/bad to use those auto-generated methods, they can really save a lot of time. All suggestions are welcome, also if you know some existing blog/discussion please let me know.

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  • ruby-on-rails: update_attributes overrides model validations?

    - by cbrulak
    I have a typical, Post model: class Post< ActiveRecord::Base validates_presence_of :user_id #Line 1 validates_presence_of :title,:body #Line 2 in the controller, I have: def create if request.post? if login_required @post = Post.new(params[:post]) #Line 3 @post .update_attribute("user_id",session[:userid]) #Line 4 However, if the validations on Line 2 fail the Post will still be created, unless Line 4 is commented out. 1) Why? 2) Suggestions on a fix? Thanks

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  • redoing object model construction to fit with asynchronous data fetching

    - by Andrew Patterson
    I have a modeled a set of objects that correspond with some real world concepts. TradeDrug, GenericDrug, TradePackage, DrugForm Underlying the simple object model I am trying to provide is a complex medical terminology that uses numeric codes to represent relationships and concepts, all accessible via a REST service - I am trying to hide away some of that complexity with an object wrapper. To give a concrete example I can call TradeDrug d = Searcher.FindTradeDrug("Zoloft") or TradeDrug d = new TradeDrug(34) where 34 might be the code for Zoloft. This will consult a remote server to find out some details about Zoloft. I might then call GenericDrug generic = d.EquivalentGeneric() System.Out.WriteLine(generic.ActiveIngredient().Name) in order to get back the generic drug sertraline as an object (again via a background REST call to the remote server that has all these drug details), and then perhaps find its ingredient. This model works fine and is being used in some applications that involve data processing. Recently however I wanted to do a silverlight application that used and displayed these objects. The silverlight environment only allows asynchronous REST/web service calls. I have no problems with how to make the asychhronous calls - but I am having trouble with what the design should be for my object construction. Currently the constructors for my objects do some REST calls sychronously. public TradeDrug(int code) { form = restclient.FetchForm(code) name = restclient.FetchName(code) etc.. } If I have to use async 'events' or 'actions' in order to use the Silverlight web client (I know silverlight can be forced to be a synchronous client but I am interested in asychronous approaches), does anyone have an guidance or best practice for how to structure my objects. I can pass in an action callback to the constructor public TradeDrug(int code, Action<TradeDrug> constructCompleted) { } but this then allows the user to have a TradeDrug object instance before what I want to construct is actually finished. It also doesn't support an 'event' async pattern because the object doesn't exist to add the event to until it is constructed. Extending that approach might be a factory object that itself has an asynchronous interface to objects factory.GetTradeDrugAsync(code, completedaction) or with a GetTradeDrugCompleted event? Does anyone have any recommendations?

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  • Can't add ADO.NET Entity Model because of error

    - by Freshblood
    I am using VS 2010 Express.This error appear "Error HRESULT E_FAIL has been returned from a call to a COM compenent" When i try to Add ADO.NET Entity Data Model. VS 2008 PRO is installed on my pc too but i don't think that it is caused by VS 2008 .I tried to reinstall VS 2010 Express but still same. How can i fix it ?

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  • Domain Model + LINQ to SQL sample

    - by lmsasu
    Hello all, I wonder if there is an enterprise application sample, designed with Domain Model in the Business Logic layer and LINQ for the Data Mapper? I'm not so sure of how to use the UnitOfWork ability of LINQ to SQL in conjunction with business objects from the Business Layer. Thanks, Lucian

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  • Ajaxrequest with Wicket but multiple possilbe model values

    - by Markus Maria Miedaner
    Hi, I'm new to wicket and stuck with the following problem: I have a table with 5 rows. Each row contains 7 cells. Each cell has a unique value. Once a cell is clicked, its unqiue value should be posted to the server. I would like to register only one ajaxfallbacklink (or similar) on the table and adjust the value of the model to the unique value of cell that has been clicked. Any ideas?

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  • get request.session from a model method in django

    - by dotty
    Hay, is it possible to a get a request.session value from a model method in django? Here is what i need def html(self): Template = loader.get_template("inclusions/Template") return Template.render(Context({ 'user_id':request.session['user'].id })) user_id would be request.session['user'].id

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  • and or operator in validates_presence_of of a Ruby on Rails model

    - by user284194
    I have an entry.rb model and I'm trying to make a semi-complicated validation. I want it to require one or more of the following fields: phone, phone2, mobile, fax, email or website. How would you write the intended code? Would something like this work? validates_presence_of :phone and or :phone2 and or :mobile and or :fax and or :email and or :website

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  • Per instance dynamic fields django model

    - by Roberto Rosario
    I have a model with a JSON field or a link to a CouchDB document. I can currently access the dynamic informaction in a way such as: genericdocument.objects.get(pk=1) == genericdocument.json_field['sample subfield'] instead I would like genericdocument.sample_subfield to maintain compatibility with all the apps the project currently shares.

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  • MVC-style model binding in WCF?

    - by Mark
    I want to bind POSTed form values to parameters in my WCF operation in the same way that ASP.Net MVC allows me to do. So, for example if my form has "customer.Name" and "customer.Age" parameters, I want to make a standard HTML POST to a named endpoint/operation that takes a customer parameter and have it instantiated and populated like MVC can do... It looks like I can use WebInvoke and its UriTemplate property to map simple parameters - does anyone know if a more MVC-like model-binding way is possible? Thanks, Mark.

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  • ASP.Net MVC 2 Auto Complete Textbox With Custom View Model Attribute & EditorTemplate

    - by SeanMcAlinden
    In this post I’m going to show how to create a generic, ajax driven Auto Complete text box using the new MVC 2 Templates and the jQuery UI library. The template will be automatically displayed when a property is decorated with a custom attribute within the view model. The AutoComplete text box in action will look like the following:   The first thing to do is to do is visit my previous blog post to put the custom model metadata provider in place, this is necessary when using custom attributes on the view model. http://weblogs.asp.net/seanmcalinden/archive/2010/06/11/custom-asp-net-mvc-2-modelmetadataprovider-for-using-custom-view-model-attributes.aspx Once this is in place, make sure you visit the jQuery UI and download the latest stable release – in this example I’m using version 1.8.2. You can download it here. Add the jQuery scripts and css theme to your project and add references to them in your master page. Should look something like the following: Site.Master <head runat="server">     <title><asp:ContentPlaceHolder ID="TitleContent" runat="server" /></title>     <link href="../../Content/Site.css" rel="stylesheet" type="text/css" />     <link href="../../css/ui-lightness/jquery-ui-1.8.2.custom.css" rel="stylesheet" type="text/css" />     <script src="../../Scripts/jquery-1.4.2.min.js" type="text/javascript"></script>     <script src="../../Scripts/jquery-ui-1.8.2.custom.min.js" type="text/javascript"></script> </head> Once this is place we can get started. Creating the AutoComplete Custom Attribute The auto complete attribute will derive from the abstract MetadataAttribute created in my previous post. It will look like the following: AutoCompleteAttribute using System.Collections.Generic; using System.Web.Mvc; using System.Web.Routing; namespace Mvc2Templates.Attributes {     public class AutoCompleteAttribute : MetadataAttribute     {         public RouteValueDictionary RouteValueDictionary;         public AutoCompleteAttribute(string controller, string action, string parameterName)         {             this.RouteValueDictionary = new RouteValueDictionary();             this.RouteValueDictionary.Add("Controller", controller);             this.RouteValueDictionary.Add("Action", action);             this.RouteValueDictionary.Add(parameterName, string.Empty);         }         public override void Process(ModelMetadata modelMetaData)         {             modelMetaData.AdditionalValues.Add("AutoCompleteUrlData", this.RouteValueDictionary);             modelMetaData.TemplateHint = "AutoComplete";         }     } } As you can see, the constructor takes in strings for the controller, action and parameter name. The parameter name will be used for passing the search text within the auto complete text box. The constructor then creates a new RouteValueDictionary which we will use later to construct the url for getting the auto complete results via ajax. The main interesting method is the method override called Process. With the process method, the route value dictionary is added to the modelMetaData AdditionalValues collection. The TemplateHint is also set to AutoComplete, this means that when the view model is parsed for display, the MVC 2 framework will look for a view user control template called AutoComplete, if it finds one, it uses that template to display the property. The View Model To show you how the attribute will look, this is the view model I have used in my example which can be downloaded at the end of this post. View Model using System.ComponentModel; using Mvc2Templates.Attributes; namespace Mvc2Templates.Models {     public class TemplateDemoViewModel     {         [AutoComplete("Home", "AutoCompleteResult", "searchText")]         [DisplayName("European Country Search")]         public string SearchText { get; set; }     } } As you can see, the auto complete attribute is called with the controller name, action name and the name of the action parameter that the search text will be passed into. The AutoComplete Template Now all of this is in place, it’s time to create the AutoComplete template. Create a ViewUserControl called AutoComplete.ascx at the following location within your application – Views/Shared/EditorTemplates/AutoComplete.ascx Add the following code: AutoComplete.ascx <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %> <%     var propertyName = ViewData.ModelMetadata.PropertyName;     var propertyValue = ViewData.ModelMetadata.Model;     var id = Guid.NewGuid().ToString();     RouteValueDictionary urlData =         (RouteValueDictionary)ViewData.ModelMetadata.AdditionalValues.Where(x => x.Key == "AutoCompleteUrlData").Single().Value;     var url = Mvc2Templates.Views.Shared.Helpers.RouteHelper.GetUrl(this.ViewContext.RequestContext, urlData); %> <input type="text" name="<%= propertyName %>" value="<%= propertyValue %>" id="<%= id %>" class="autoComplete" /> <script type="text/javascript">     $(function () {         $("#<%= id %>").autocomplete({             source: function (request, response) {                 $.ajax({                     url: "<%= url %>" + request.term,                     dataType: "json",                     success: function (data) {                         response(data);                     }                 });             },             minLength: 2         });     }); </script> There is a lot going on in here but when you break it down it’s quite simple. Firstly, the property name and property value are retrieved through the model meta data. These are required to ensure that the text box input has the correct name and data to allow for model binding. If you look at line 14 you can see them being used in the text box input creation. The interesting bit is on line 8 and 9, this is the code to retrieve the route value dictionary we added into the model metada via the custom attribute. Line 11 is used to create the url, in order to do this I created a quick helper class which looks like the code below titled RouteHelper. The last bit of script is the code to initialise the jQuery UI AutoComplete control with the correct url for calling back to our controller action. RouteHelper using System.Web.Mvc; using System.Web.Routing; namespace Mvc2Templates.Views.Shared.Helpers {     public static class RouteHelper     {         const string Controller = "Controller";         const string Action = "Action";         const string ReplaceFormatString = "REPLACE{0}";         public static string GetUrl(RequestContext requestContext, RouteValueDictionary routeValueDictionary)         {             RouteValueDictionary urlData = new RouteValueDictionary();             UrlHelper urlHelper = new UrlHelper(requestContext);                          int i = 0;             foreach(var item in routeValueDictionary)             {                 if (item.Value == string.Empty)                 {                     i++;                     urlData.Add(item.Key, string.Format(ReplaceFormatString, i.ToString()));                 }                 else                 {                     urlData.Add(item.Key, item.Value);                 }             }             var url = urlHelper.RouteUrl(urlData);             for (int index = 1; index <= i; index++)             {                 url = url.Replace(string.Format(ReplaceFormatString, index.ToString()), string.Empty);             }             return url;         }     } } See it in action All you need to do to see it in action is pass a view model from your controller with the new AutoComplete attribute attached and call the following within your view: <%= this.Html.EditorForModel() %> NOTE: The jQuery UI auto complete control expects a JSON string returned from your controller action method… as you can’t use the JsonResult to perform GET requests, use a normal action result, convert your data into json and return it as a string via a ContentResult. If you download the solution it will be very clear how to handle the controller and action for this demo. The full source code for this post can be downloaded here. It has been developed using MVC 2 and Visual Studio 2010. As always, I hope this has been interesting/useful. Kind Regards, Sean McAlinden.

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  • ASP.NET MVC 2 Model Binding for a Collection

    - by nmarun
    Yes, my yet another post on Model Binding (previous one is here), but this one uses features presented in MVC 2. How I got to writing this blog? Well, I’m on a project where we’re doing some MVC things for a shopping cart. Let me show you what I was working with. Below are my model classes: 1: public class Product 2: { 3: public int Id { get; set; } 4: public string Name { get; set; } 5: public int Quantity { get; set; } 6: public decimal UnitPrice { get; set; } 7: } 8:   9: public class Totals 10: { 11: public decimal SubTotal { get; set; } 12: public decimal Tax { get; set; } 13: public decimal Total { get; set; } 14: } 15:   16: public class Basket 17: { 18: public List<Product> Products { get; set; } 19: public Totals Totals { get; set;} 20: } The view looks as below:  1: <h2>Shopping Cart</h2> 2:   3: <% using(Html.BeginForm()) { %> 4: 5: <h3>Products</h3> 6: <% for (int i = 0; i < Model.Products.Count; i++) 7: { %> 8: <div style="width: 100px;float:left;">Id</div> 9: <div style="width: 100px;float:left;"> 10: <%= Html.TextBox("ID", Model.Products[i].Id) %> 11: </div> 12: <div style="clear:both;"></div> 13: <div style="width: 100px;float:left;">Name</div> 14: <div style="width: 100px;float:left;"> 15: <%= Html.TextBox("Name", Model.Products[i].Name) %> 16: </div> 17: <div style="clear:both;"></div> 18: <div style="width: 100px;float:left;">Quantity</div> 19: <div style="width: 100px;float:left;"> 20: <%= Html.TextBox("Quantity", Model.Products[i].Quantity)%> 21: </div> 22: <div style="clear:both;"></div> 23: <div style="width: 100px;float:left;">Unit Price</div> 24: <div style="width: 100px;float:left;"> 25: <%= Html.TextBox("UnitPrice", Model.Products[i].UnitPrice)%> 26: </div> 27: <div style="clear:both;"><hr /></div> 28: <% } %> 29: 30: <h3>Totals</h3> 31: <div style="width: 100px;float:left;">Sub Total</div> 32: <div style="width: 100px;float:left;"> 33: <%= Html.TextBox("SubTotal", Model.Totals.SubTotal)%> 34: </div> 35: <div style="clear:both;"></div> 36: <div style="width: 100px;float:left;">Tax</div> 37: <div style="width: 100px;float:left;"> 38: <%= Html.TextBox("Tax", Model.Totals.Tax)%> 39: </div> 40: <div style="clear:both;"></div> 41: <div style="width: 100px;float:left;">Total</div> 42: <div style="width: 100px;float:left;"> 43: <%= Html.TextBox("Total", Model.Totals.Total)%> 44: </div> 45: <div style="clear:both;"></div> 46: <p /> 47: <input type="submit" name="Submit" value="Submit" /> 48: <% } %> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Nothing fancy, just a bunch of div’s containing textboxes and a submit button. Just make note that the textboxes have the same name as the property they are going to display. Yea, yea, I know. I’m displaying unit price as a textbox instead of a label, but that’s beside the point (and trust me, this will not be how it’ll look on the production site!!). The way my controller works is that initially two dummy products are added to the basked object and the Totals are calculated based on what products were added in what quantities and their respective unit price. So when the page loads in edit mode, where the user can change the quantity and hit the submit button. In the ‘post’ version of the action method, the Totals get recalculated and the new total will be displayed on the screen. Here’s the code: 1: public ActionResult Index() 2: { 3: Product product1 = new Product 4: { 5: Id = 1, 6: Name = "Product 1", 7: Quantity = 2, 8: UnitPrice = 200m 9: }; 10:   11: Product product2 = new Product 12: { 13: Id = 2, 14: Name = "Product 2", 15: Quantity = 1, 16: UnitPrice = 150m 17: }; 18:   19: List<Product> products = new List<Product> { product1, product2 }; 20:   21: Basket basket = new Basket 22: { 23: Products = products, 24: Totals = ComputeTotals(products) 25: }; 26: return View(basket); 27: } 28:   29: [HttpPost] 30: public ActionResult Index(Basket basket) 31: { 32: basket.Totals = ComputeTotals(basket.Products); 33: return View(basket); 34: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } That’s that. Now I run the app, I see two products with the totals section below them. I look at the view source and I see that the input controls have the right ID, the right name and the right value as well. 1: <input id="ID" name="ID" type="text" value="1" /> 2: <input id="Name" name="Name" type="text" value="Product 1" /> 3: ... 4: <input id="ID" name="ID" type="text" value="2" /> 5: <input id="Name" name="Name" type="text" value="Product 2" /> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } So just as a regular user would do, I change the quantity value of one of the products and hit the submit button. The ‘post’ version of the Index method gets called and I had put a break-point on line 32 in the above snippet. When I hovered my mouse on the ‘basked’ object, happily assuming that the object would be all bound and ready for use, I was surprised to see both basket.Products and basket.Totals were null. Huh? A little research and I found out that the reason the DefaultModelBinder could not do its job is because of a naming mismatch on the input controls. What I mean is that when you have to bind to a custom .net type, you need more than just the property name. You need to pass a qualified name to the name property of the input control. I modified my view and the emitted code looked as below: 1: <input id="Product_Name" name="Product.Name" type="text" value="Product 1" /> 2: ... 3: <input id="Product_Name" name="Product.Name" type="text" value="Product 2" /> 4: ... 5: <input id="Totals_SubTotal" name="Totals.SubTotal" type="text" value="550" /> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now, I update the quantity and hit the submit button and I see that the Totals object is populated, but the Products list is still null. Once again I went: ‘Hmm.. time for more research’. I found out that the way to do this is to provide the name as: 1: <%= Html.TextBox(string.Format("Products[{0}].ID", i), Model.Products[i].Id) %> 2: <!-- this will be rendered as --> 3: <input id="Products_0__ID" name="Products[0].ID" type="text" value="1" /> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } It was only now that I was able to see both the products and the totals being properly bound in the ‘post’ action method. Somehow, I feel this is kinda ‘clunky’ way of doing things. Seems like people at MS felt in a similar way and offered us a much cleaner way to solve this issue. The simple solution is that instead of using a Textbox, we can either use a TextboxFor or an EditorFor helper method. This one directly spits out the name of the input property as ‘Products[0].ID and so on. Cool right? I totally fell for this and changed my UI to contain EditorFor helper method. At this point, I ran the application, changed the quantity field and pressed the submit button. Of course my basket object parameter in my action method was correctly bound after these changes. I let the app complete the rest of the lines in the action method. When the page finally rendered, I did see that the quantity was changed to what I entered before the post. But, wait a minute, the totals section did not reflect the changes and showed the old values. My status: COMPLETELY PUZZLED! Just to recap, this is what my ‘post’ Index method looked like: 1: [HttpPost] 2: public ActionResult Index(Basket basket) 3: { 4: basket.Totals = ComputeTotals(basket.Products); 5: return View(basket); 6: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } A careful debug confirmed that the basked.Products[0].Quantity showed the updated value and the ComputeTotals() method also returns the correct totals. But still when I passed this basket object, it ended up showing the old totals values only. I began playing a bit with the code and my first guess was that the input controls got their values from the ModelState object. For those who don’t know, the ModelState is a temporary storage area that ASP.NET MVC uses to retain incoming attempted values plus binding and validation errors. Also, the fact that input controls populate the values using data taken from: Previously attempted values recorded in the ModelState["name"].Value.AttemptedValue Explicitly provided value (<%= Html.TextBox("name", "Some value") %>) ViewData, by calling ViewData.Eval("name") FYI: ViewData dictionary takes precedence over ViewData's Model properties – read more here. These two indicators led to my guess. It took me quite some time, but finally I hit this post where Brad brilliantly explains why this is the preferred behavior. My guess was right and I, accordingly modified my code to reflect the following way: 1: [HttpPost] 2: public ActionResult Index(Basket basket) 3: { 4: // read the following posts to see why the ModelState 5: // needs to be cleared before passing it the view 6: // http://forums.asp.net/t/1535846.aspx 7: // http://forums.asp.net/p/1527149/3687407.aspx 8: if (ModelState.IsValid) 9: { 10: ModelState.Clear(); 11: } 12:   13: basket.Totals = ComputeTotals(basket.Products); 14: return View(basket); 15: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } What this does is that in the case where your ModelState IS valid, it clears the dictionary. This enables the values to be read from the model directly and not from the ModelState. So the verdict is this: If you need to pass other parameters (like html attributes and the like) to your input control, use 1: <%= Html.TextBox(string.Format("Products[{0}].ID", i), Model.Products[i].Id) %> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Since, in EditorFor, there is no direct and simple way of passing this information to the input control. If you don’t have to pass any such ‘extra’ piece of information to the control, then go the EditorFor way. The code used in the post can be found here.

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