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  • Entity Framework: insert with one-to-one reference

    - by bomortensen
    Hi 'overflow! I'm having a bit trouble inserting into a mssql database using Entity Framework. There's two tables that I want to insert into, where one of table 1s fields is a foreign key in table2. This is the code I have so far: Media media = null; foreach(POI p in poiList) { media = new Media() { Path = p.ImagePath, Title = p.Title }; if (media != null && !context.Media.Any(me => me.Title == p.ImageTitle)) { context.AddToMedia(media); context.SaveChanges(); } PointOfInterest poi = new PointOfInterest() { Altitude = 2000.0, ID = p.ID, Latitude = p.Latitude, Longitude = p.Longitude, LatitudeRoute = p.LatitudeRoute, LongitudeRoute = p.LongitudeRoute, Description = p.Description, Title = p.Title, DefaultImageID = media.ID, }; context.AddToPointOfInterest(poi); } context.SaveChanges(); The following gives me this error: An object with the same key already exists in the ObjectStateManagerAn object with the same key already exists in the ObjectStateManager I'm still learning how to use the entity framework, so I don't even know if this would be the right approach to insert into two referenced tables. Can anyone enlighten me on this? :) Any help would be greatly appreciated! Thanks!

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  • Looking for a communication framework for delphi

    - by Ryan
    I am looking for a communication framework for delphi, we know there are so many communication frameworks for other languages , wcf, ecf and so forth, but i have nerver found the one for delphi till now , anybody who knows about it can give me an ider? There are some requirements i need ,as follows: Building an application(server or client) without caring how to do communications with each other between two endpoints. Imagine that we use mailbox for exchanging messages,it seems that the communication is transparent. Supports communication protocol extending. We often need to exchange the messages between 2 devices, but the communication protocol is not a public or general one, so we need to extend the framework,to implement a communication protocol for receiving or sending a message completely. Supports asynchronous and synchronous communication Supports transmission protocol extending. The transmission protocol can implemented by winsocket, pipes, com, windows message, mailslot and so forth. In client application, we can write code snips like follows: var server: TDelphiCommunicationServer; session : ICommunicationSession; request, response: IMessage; begin session := server.CreateSession('IP', Port); request := TLoginRequest.Create; session.SynSendMessage(request); session.WaitForMessage(response, INFINITE); ....... end; In above code snips , TLoginRequest has implemented the message interface.

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  • A small, intra-app Object to String Serializer

    - by Rick Strahl
    On a few occasions I've needed a very compact serializer for small and simple, flat object serialization, typically for storage in Cookies or a FormsAuthentication ticket in ASP.NET. XML and JSON serialization are too verbose for those scenarios so a simple property serializer that strings together the values was needed. Originally I did this by hand, but here is a class that automates the process.

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  • Using Entity Framework with an SQL Compact Private Installation

    - by David Veeneman
    I am using Entity Framework 4 in a desktop application with SQL Compact. I want to use a private installation of SQL Compact with my application, so that my installer can install SQL Compact without giving the user a second installation to do. It also avoids versioning hassles down the road. My development machine has SQL Compact 3.5 SP1 installed as a public installation, so my app runs fine there, as one would expect. But it's not running on my test machine, which does not have SQL Compact installed. I get this error: The specified store provider cannot be found in the configuration, or is not valid. I know some people have had difficulty with SQL Compact private installations, but I have used them for a while, and I really like them. Unfortunately, my regular private installation approach isn't working. I have checked the version numbers on my SQL CE files, and they are all 3.8.8078.0, which is the SP2 RC version. Here are the files I have included in my private installation: sqlcecompact35.dll sqlceer35EN.dll sqlceme35.dll sqlceqp35.dll sqlcese35.dll System.Data.SqlServerCe.dll System.Data.SqlServerCe.Entity.dll I have added a reference to System.Data.SqlServerCe to my project, and I have verified that all of the files listed above are being copied to the application folder on the installation machine. Here is the code I use to configure an EntityConnectionStringBuilder when I open a SQL Compact file: var sqlCompactConnectionString = string.Format("Data Source={0}", filePath); // Set Builder properties builder.Metadata = string.Format("res://*/{0}.csdl|res://*/{0}.ssdl|res://*/{0}.msl", edmName); builder.Provider = "System.Data.SqlServerCe.3.5"; builder.ProviderConnectionString = sqlCompactConnectionString; var edmConnectionString = builder.ToString(); Am I missing a file? Am I missing a configuration stepp needed to tell Entity Framework where to find my SQL Compact DLLs? Any other suggestions why EF isn't finding my SQL Compact DLLs on the installation machine? Thanks for your help.

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  • What do you do when a client requires Rich Text Editing on their website?

    - by George Stocker
    As we all know by now, XSS attacks are dangerous and really easy to pull off. Various frameworks make it easy to encode HTML, like ASP.NET MVC does: <%= Html.Encode("string"); %> But what happens when your client requires that they be able to upload their content directly from a Microsoft Word document? Here's the scenario: People can copy and paste content from Microsoft word into a WYSIWYG editor (in this case tinyMCE), and then that information is posted to a web page. The website is public, but only members of that organization will have access to post information to a webpage. What is the best way to handle this requirement? Currently there is no checking done on what the client posts (since only 'trusted' users can post), but I'm not particularly happy with that and would like to lock it down further in case an account is hacked. The platform in question is ASP.NET MVC. The only conceptual method that I'm aware of that meets these requirements is to whitelist HTML tags and let those pass through. Is there another way? If not, is the best way to let them store it in the Database in any form, but only display it properly encoded and stripped of bad tags? NB: The questions differ in that he only assumes there's one way. I'm also asking the following questions: 1. Is there a better way that doesn't rely on HTML Whitelists? 2. Is there a better way that relies on a different view engine? 3. Is there a WYSIWYG editor that includes the ability to whitelist on the fly? 4. Should I even worry about this since it will only be for 'private posting' (Much in the same way that a private blog allows HTML From the author, but since only he can post, it's not an issue)? Edit #2: If suggesting a WYSIWYG editor, it must be free (as in speech, or as in beer). Update: All of the suggestions thus far revolve around a specific Rich Text Editor to use: Only provide an editor as a suggestion if it allows for sanitization of HTML tags; and it fulfills the requirement of accepting pasted documents from a WYSIWYG Editor like Microsoft Word. There are three methods that I know of: 1. Not allow HTML. 2. Allow HTML, but sanitize it 3. Find a Rich Text Editor that sanitizes and allows HTML. The previous questions remain (1-4 above). Related Question Preventing Cross Site Scripting (XSS)

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  • Zend Framework how to echo value of SUM query

    - by Rick de Graaf
    Hello, I created a query for the zend framework, in which I try to retrieve the sum of a column, in this case the column named 'time'. This is the query I use: $this->timequery = $this->db_tasks->fetchAll($this->db_tasks->select()->from('tasks', 'SUM(time)')->where('projectnumber =' . $this->value_project)); $this->view->sumtime = $this->timequery; Echoing the query tells me this is right. But I can't echo the result properly. Currently I'm using: echo $this->sumtime['SUM(time)']; Returning the following error: Catchable fatal error: Object of class Zend_Db_Table_Row could not be converted to string in C:\xampp\htdocs\BManagement\application\views\scripts\tasks\index.phtml on line 46 Line 46 being the line with the echo in my view. I've been searching now for two days on how to figure this out, or achieve the same result in a different way. Tried to serialize the value, but that didn't work either. Is there somebody who knows how to achieve the total sum of a database column? Any help is greatly appriciated! note: Pretty new to zend framework...

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  • Choosing a Java Web Framework now?

    - by hbagchi
    we are in the planning stage of migrating a large website which is built on a custom developed mvc framework to a java based web framework which provides built-in support for ajax, rich media content, mashup, templates based layout, validation, maximum html/java code separation. Grails looked like a good choice, however, we do not want to use a scripting language. We want to continue using java. Template based layout is a primary concern as we intend to use this web application with multiple web sites with similar functionality but radically different look and feel. Is portal based solution a good fit to this problem? Any insights on using "Spring Roo" or "Play" will be very helpful. I did find similar posts like this, but it is more than a year old. Things have surely changed in the mean time! EDIT 1: Thanks for the great answers! This site is turning to be the best single source for in-the-trenches programmer info. However, I was expecting more info on using a portal-cms duo. Jahia looks goods. Anything similar?

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  • Java Playing Cards Game Framework

    - by isme
    My friends and I at uni love playing Shithead into the wee hours. But soon we graduate and will leave town, so probably won't get together for a game for a while. I want to develop a Java app we can use to play Shithead and our other favorites over a network. An app like this already exists, but is ugly, buggy and does not support our house rules. The source is available, but is such a mess that I would really rather start from scratch than try to refactor it! Building my game using some standard playing card api or framework, if such a thing exists, would be better than starting from scratch. The answer to a similar SO question was to use the JPC-API, which allegedly provides basic playing card services and rendering. But this Sourceforge project currently makes available no files or source code! Is there an alternative, or somewhere else to find this framework? Soon I will need help with the following as well: Lobby services (finding other players) Gaming network protocol (to communicate moves between players) Gaming theory (to write the computer opponent) Winning condition detection Game UI development

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  • ASP.NET MVC 3 Hosting :: How to Upgrade ASP.NET MVC 2 Project to ASP.NET MVC 3

    - by mbridge
    ASP.NET MVC 3 can be installed side by side with ASP.NET MVC 2 on the same computer, which gives you flexibility in choosing when to upgrade an ASP.NET MVC 2 application to ASP.NET MVC 3. The simplest way to upgrade is to create a new ASP.NET MVC 3 project and copy all the views, controllers, code, and content files from the existing MVC 2 project to the new project and then to update the assembly references in the new project to match the old project. If you have made changes to the Web.config file in the MVC 2 project, you must also merge those changes with the Web.config file in the MVC 3 project. To manually upgrade an existing ASP.NET MVC 2 application to version 3, do the following: 1. In both Web.config files in the MVC 3 project, globally search and replace the MVC version. Find the following: System.Web.Mvc, Version=2.0.0.0 Replace it with the following System.Web.Mvc, Version=3.0.0.0 There are three changes in the root Web.config and four in the Views\Web.config file. 2. In Solution Explorer, delete the reference to System.Web.Mvc (which points to the version 2 DLL). Then add a reference to System.Web.Mvc (v3.0.0.0). 3. In Solution Explorer, right-click the project name and then select Unload Project. Then right-click again and select Edit ProjectName.csproj. 4. Locate the ProjectTypeGuids element and replace {F85E285D-A4E0-4152-9332-AB1D724D3325} with {E53F8FEA-EAE0-44A6-8774-FFD645390401}. 5. Save the changes and then right-click the project and select Reload Project. 6. If the project references any third-party libraries that are compiled using ASP.NET MVC 2, add the following highlighted bindingRedirect element to the Web.config file in the application root under the configuration section: <runtime>   <assemblyBinding >     <dependentAssembly>       <assemblyIdentity name="System.Web.Mvc"           publicKeyToken="31bf3856ad364e35"/>       <bindingRedirect oldVersion="2.0.0.0" newVersion="3.0.0.0"/>     </dependentAssembly>   </assemblyBinding> </runtime> Another ASP.NET MVC 3 article: - Rolling with Razor in MVC v3 Preview - Deploying ASP.NET MVC 3 web application to server where ASP.NET MVC 3 is not installed - RenderAction with ASP.NET MVC 3 Sessionless Controllers

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  • Help me understand entity framework 4 caching for lazy loading

    - by Chris
    I am getting some unexpected behaviour with entity framework 4.0 and I am hoping someone can help me understand this. I am using the northwind database for the purposes of this question. I am also using the default code generator (not poco or self tracking). I am expecting that anytime I query the context for the framework to only make a round trip if I have not already fetched those objects. I do get this behaviour if I turn off lazy loading. Currently in my application I am breifly turning on lazy loading and then turning it back off so I can get the desired behaviour. That pretty much sucks, so please help. Here is a good code example that can demonstrate my problem. Public Sub ManyRoundTrips() context.ContextOptions.LazyLoadingEnabled = True Dim employees As List(Of Employee) = context.Employees.Execute(System.Data.Objects.MergeOption.AppendOnly).ToList() 'makes unnessesary round trip to the database, I just loaded the employees' MessageBox.Show(context.Employees.Where(Function(x) x.EmployeeID < 10).ToList().Count) context.Orders.Execute(System.Data.Objects.MergeOption.AppendOnly) For Each emp As Employee In employees 'makes unnessesary trip to database every time despite orders being pre loaded.' Dim i As Integer = emp.Orders.Count Next End Sub Public Sub OneRoundTrip() context.ContextOptions.LazyLoadingEnabled = True Dim employees As List(Of Employee) = context.Employees.Include("Orders").Execute(System.Data.Objects.MergeOption.AppendOnly).ToList() MessageBox.Show(employees.Where(Function(x) x.EmployeeID < 10).ToList().Count) For Each emp As Employee In employees Dim i As Integer = emp.Orders.Count Next End Sub Why is the first block of code making unnessesary round trips?

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  • Zend Framework cleaning default routes when adding other

    - by Renato Aquino
    I have the following problem with Zend Framework. My project has several controllers like Video,Category and Post. The VideoController has an Action called categorylist, so the default URL/Route becomes /video/categorylist Since the action requires 3 parameters I whant to add one simple route: $router->addRoute( 'categorylist', new Zend_Controller_Router_Route('categorylist/:category/:page/:per_page', array('controller' => 'video', 'action' => 'categorylist','page'=>1,'per_page'=>6,'category'=>1)) ); With this I got my URL like www.siteurl.com/categorylist/42/1/6 but, the View Helper URL got crazy, and every url for the other controllers I try to echo it´s redirected to the categorylist route. So when I try this: <?= $this->url(array("controller"=> "video", "action" =>"view",'category'=>1),null,true)?> The expected result its /video/view/category/1, but I got /categorylit only. I tryied to debug the default routes but I got an empty array. print_r($ctrl->getRouter()->getRoutes()); Does anyone have some clue about this wierd behavior? I´m using Zend Framework Version 1.9.7

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  • How do I tell the cases when it's worth to use LINQ?

    - by Lijo
    Many things in LINQ can be accomplished without the library. But for some scenarios, LINQ is most appropriate. Examples are: SELECT - http://stackoverflow.com/questions/11883262/wrapping-list-items-inside-div-in-a-repeater SelectMany, Contains - http://stackoverflow.com/questions/11778979/better-code-pattern-for-checking-existence-of-value Enumerable.Range - http://stackoverflow.com/questions/11780128/scalable-c-sharp-code-for-creating-array-from-config-file WHERE http://stackoverflow.com/questions/13171850/trim-string-if-a-string-ends-with-a-specific-word What factors to take into account when deciding between LINQ and regular .Net language elements?

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  • Sync Framework Considerations for Smart Client app

    - by DarkwingDuck
    Microsoft Sync Framework with SQL 2005? Is it possible? It seems to hint that the OOTB providers use SQL2008 functionality. I'm looking for some quick wins in relation to a sync project. The client app will be offline for a number of days. There will be a central server that MUST be SQL Server 2005. I can use .net 3.5. Basically the client app could go offline for a week. When it comes back online it needs to sync its data. But the good thing is that the data only needs to push to the server. The stuff that syncs back to the client will just be lookup data which the client never changes. So this means I don't care about sync collisions. To simplify the scenario for you, this smart client goes offline and the user surveys data about some observations. They enter the data into the system. When the laptop is reconnected to the network, it syncs back all that data to the server. There will be other clients doing the same thing too, but no one ever touches each other's data. Then there are some reports on the server for viewing the data that has been pushed to the server. This also needs to use ClickOnce. My biggest concern is that there is an interim release while a client is offline. This release might require a new field in the database, and a new field to fill in on the survey. Obviously that new field will be nullable because we can't update old data, that's fine to set as an assumption. But when the client connects up and its local data schema and the server schema don't match, will sync framework be able to handle this? After the data is pushed to the server it is discarded locally. Hope my problem makes sense.

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  • Understanding many to many relationships and Entity Framework

    - by Anders Svensson
    I'm trying to understand the Entity Framework, and I have a table "Users" and a table "Pages". These are related in a many-to-many relationship with a junction table "UserPages". First of all I'd like to know if I'm designing this relationship correctly using many-to-many: One user can visit multiple pages, and each page can be visited by multiple users..., so am I right in using many2many? Secondly, and more importantly, as I have understood m2m relationships, the User and Page tables should not repeat information. I.e. there should be only one record for each user and each page. But then in the entity framework, how am I able to add new visits to the same page for the same user? That is, I was thinking I could simply use the Count() method on the IEnumerable returned by a LINQ query to get the number of times a user has visited a certain page. But I see no way of doing that. In Linq to Sql I could access the junction table and add records there to reflect added visits to a certain page by a certain user, as many times as necessary. But in the EF I can't access the junction table. I can only go from User to a Pages collection and vice versa. I'm sure I'm misunderstanding relationships or something, but I just can't figure out how to model this. I could always have a Count column in the Page table, but as far as I have understood you're not supposed to design database tables like that, those values should be collected by queries... Please help me understand what I'm doing wrong...

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  • Entity Framework in layered architecture

    - by Kamyar
    I am using a layered architecture with the Entity Framework. Here's What I came up with till now (All the projects Except UI are class library): Entities: The POCO Entities. Completely persistence ignorant. No Reference to other projects. Generated by Microsoft's ADO.Net POCO Entity Generator. DAL: The EDMX (Entity Model) file with the context class. (t4 generated). References: Entities BLL: Business Logic Layer. Will implement repository pattern on this layer. References: Entities, DAL. This is where the objectcontext gets populated: var ctx=new DAL.MyDBEntities(); UI: The presentation layer: ASP.NET website. References: Entities, BLL + a connection string entry to entities in the config file (question #2). Now my three questions: Is my layer discintion approach correct? In my UI, I access BLL as follows: var customerRep = new BLL.CustomerRepository(); var Customer = customerRep.GetByID(myCustomerID); The problem is that I have to define the entities connection string in my UI's web.config/app.config otherwise I get a runtime exception. IS defining the entities connectionstring in UI spoils the layers' distinction? Or is it accesptible in a muli layered architecture. Should I take any additional steps to perform chage tracking, lazy loading, etc (by etc I mean the features that Entity Framework covers in a conventional, 1 project, non POCO code generation)? Thanks and apologies for the lengthy question.

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  • How to load entities into readonly collections using the entity framework

    - by Anton P
    I have a POCO domain model which is wired up to the entity framework using the new ObjectContext class. public class Product { private ICollection<Photo> _photos; public Product() { _photos = new Collection<Photo>(); } public int Id { get; set; } public string Name { get; set; } public virtual IEnumerable<Photo> Photos { get { return _photos; } } public void AddPhoto(Photo photo) { //Some biz logic //... _photos.Add(photo); } } In the above example i have set the Photos collection type to IEnumerable as this will make it read only. The only way to add/remove photos is through the public methods. The problem with this is that the Entity Framework cannot load the Photo entities into the IEnumerable collection as it's not of type ICollection. By changing the type to ICollection will allow callers to call the Add mentod on the collection itself which is not good. What are my options?

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  • Entity Framework: Auto-updating foreign key when setting a new object reference

    - by Adrian Grigore
    Hi, I am porting an existing application from Linq to SQL to Entity Framework 4 (default code generation). One difference I noticed between the two is that a foreign key property are not updated when resetting the object reference. Now I need to decide how to deal with this. For example supposing you have two entity types, Company and Employee. One Company has many Employees. In Linq To SQL, setting the company also sets the company id: var company=new Company(ID=1); var employee=new Employee(); Debug.Assert(employee.CompanyID==0); employee.Company=company; Debug.Assert(employee.CompanyID==1); //Works fine! In Entity Framework (and without using any code template customization) this does not work: var company=new Company(ID=1); var employee=new Employee(); Debug.Assert(employee.CompanyID==0); employee.Company=company; Debug.Assert(employee.CompanyID==1); //Throws, since CompanyID was not updated! How can I make EF behave the same way as LinqToSQL? I had a look at the default code generation T4 template, but I could not figure out how to make the necessary changes.

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  • Zend Framework - counting rows in select clause ?

    - by moogeek
    Hello! I'm investigating Zend Framework and currently stucked in counting resulting rows of sql query... Every method I try (from documentation and some blogposts and tutorials) returns an error (like Call to undefined function) or simply gives the incorrect value. I've tried this: $checkquery = $db->select() ->from('users', 'COUNT(*)') ->where('login = ?', $login) ->where('password = ?', $password) ->query(); $checkrequest=fetchRow($checkquery)->num; ...then this one: $checkquery = $db->select() ->from('users', '*') ->where('login = ?', $login) ->where('password = ?', $password) ->query(); $checkrequest=count($checkquery->fetchAll()); and even: $checkquery = $db->select() ->from('users', '*') ->where('login = ?', $login) ->where('password = ?', $password) ->query(); $checkrequest=$checkquery->fetchAll()->num; Also rowCount() and count(fetchRow()) and count(fetchAll()->toArray()). But always I got an error message or duplicate inserts in db in further insert function. So what is the correct way to do the resulting row calculation in select clause in Zend Framework 1.9 (I use this one) ?

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  • entity framework insert bug

    - by tmfkmoney
    I found a previous question which seemed related but there's no resolution and it's 5 months old so I've opened my own version. http://stackoverflow.com/questions/1545583/entity-framework-inserting-new-entity-via-objectcontext-does-not-use-existing-e When I insert records into my database with the following it works fine for a while and then eventually it starts inserting null values in the referenced field. This typically happens after I do an update on my model from the database although not always after I do an update. I'm using a MySQL database for this. I have debugged the code and the values are being set properly before the save event. They're just not getting inserted properly. I can always fix this issue by re-creating the model without touching any of my code. I have to recreate the entire model, though. I can't just dump the relevant tables and re-add them. This makes me think it doesn't have anything to do with my code but something with the entity framework. Does anyone else have this problem and/or solved it? using (var db = new MyModel()) { var stocks = from record in query let ticker = record.Ticker select new { company = db.Companies.FirstOrDefault(c => c.ticker == ticker), price = Convert.ToDecimal(record.Price), date_stamp = Convert.ToDateTime(record.DateTime) }; foreach (var stock in stocks) { if (stock.company != null) { var price = new StockPrice { Company = stock.company, price = stock.price, date_stamp = stock.date_stamp }; db.AddToStockPrices(price); } } db.SaveChanges(); }

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  • Entity Framework 4 + POCO with custom classes and WCF contracts (serialization problem)

    - by eman
    Yesterday I worked on a project where I upgraded to Entity Framework 4 with the Repository pattern. In one post, I have read that it is necessary to turn off the custom tool generator classes and then write classes (same like entites) by hand. That I can do it, I used the POCO Entity Generator and then deleted the new generated files .tt and all subordinate .cs classes. Then I wrote the "entity classes" by myself. I added the repository pattern and implemented it in the business layer and then implemented a WCF layer, which should call the methods from the business layer. By calling an Insert (Add) method from the presentation layer and everything is OK. But if I call any method that should return some class, then I get an error like (the connection was interrupted by the server). I suppose there is a problem with the serialization or am I wrong? How can by this problem solved? I'm using Visual Studio S2010, Entity Framework 4, C#. UPDATE: I have uploaded the project and hope somebody can help me! link text UPDATE 2: My questions: Why is POCO good (pros/cons)? When should POCO be used? Is POCO + the repository pattern a good choice? Should POCO classes by written by myself or could I use auto generated POCO classes?

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  • Howto use predicates in LINQ to Entities for Entity Framework objects

    - by user274947
    I'm using LINQ to Entities for Entity Framework objects in my Data Access Layer. My goal is to filter as much as I can from the database, without applying filtering logic on in-memory results. For that purpose Business Logic Layer passes a predicate to Data Access Layer. I mean Func<MyEntity, bool> So, if I use this predicate directly, like public IQueryable<MyEntity> GetAllMatchedEntities(Func<MyEntity, Boolean> isMatched) { return qry = _Context.MyEntities.Where(x => isMatched(x)); } I'm getting the exception [System.NotSupportedException] --- {"The LINQ expression node type 'Invoke' is not supported in LINQ to Entities."} Solution in that question suggests to use AsExpandable() method from LINQKit library. But again, using public IQueryable<MyEntity> GetAllMatchedEntities(Func<MyEntity, Boolean> isMatched) { return qry = _Context.MyEntities.AsExpandable().Where(x => isMatched(x)); } I'm getting the exception Unable to cast object of type 'System.Linq.Expressions.FieldExpression' to type 'System.Linq.Expressions.LambdaExpression' Is there way to use predicate in LINQ to Entities query for Entity Framework objects, so that it is correctly transformed it into a SQL statement. Thank you.

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  • AJAX or a server side framework?

    - by Romansky
    I am working with a friend on building a web site, in general this web site will be a custom web app along with a very custom social network type of thing.. Currently I have a mock-up site that uses simple PHP with AJAX and JSON and JQUERY and I love how it works, I love the way it all fits together. But for a mock-up I did not implement any of the Social Network design patterns such as a login, rating, groups etc.. This brought me to a higher level of decision making requirement, I need to decide if I want to develop all this functionality by hand or use some kind of a framework. I spent this entire day researching, and it would seem that using Drupal and such frameworks will make the Social Network part easy (overlooking the customization requirement for now..) but will make client side Web App development less so. I found some other frameworks that are more developer friendly (customizable) such as Zend and Symfony etc.. but these seem to take allot of the power from the client and implement it in the server side, to me this seems a waste (and an unjustified performance bottleneck) .. Finally I found Aptana Jaxer framework that seems to think the same way I feel. That said it seems a bit under-developed, I didn't find modules for a social network and the community around it seems thin.. (searching Jaxer in StackOverflow returns few results) So other then making server side DB comm a bit simpler it does not help me greatly.. My requirements are a good facility to develop web apps on while containing all the user centric logic usually used for social networks in advance. What would you recommend? EDIT: OK, lats fine tune this question, after considering this abit further, is there a good down loadable source of a social network site in PHP that I can work around in building my web app? (I really like using JQUERY AJAX JSON etc..)

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  • entity framework navigation property further filter without loading into memory

    - by cellik
    Hi, I've two entities with 1 to N relation in between. Let's say Books and Pages. Book has a navigation property as Pages. Book has BookId as an identifier and Page has an auto generated id and a scalar property named PageNo. LazyLoading is set to true. I've generated this using VS2010 & .net 4.0 and created a database from that. In the partial class of Book, I need a GetPage function like below public Page GetPage(int PageNumber) { //checking whether it exist etc are not included for simplicity return Pages.Where(p=>p.PageNo==PageNumber).First(); } This works. However, since Pages property in the Book is an EntityCollection it has to load all Pages of a book in memory in order to get the one page (this slows down the app when this function is hit for the first time for a given book). i.e. Framework does not merge the queries and run them at once. It loads the Pages in memory and then uses LINQ to objects to do the second part To overcome this I've changed the code as follows public Page GetPage(int PageNumber) { MyContainer container = new MyContainer(); return container.Pages.Where(p=>p.PageNo==PageNumber && p.Book.BookId==BookId).First(); } This works considerably faster however it doesn't take into account the pages that have not been serialized to the db. So, both options has its cons. Is there any trick in the framework to overcome this situation. This must be a common scenario where you don't want all of the objects of a Navigation property loaded in memory when you don't need them.

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  • Entity framework self referencing loop detected

    - by Lyd0n
    I have a strange error. I'm experimenting with a .NET 4.5 Web API, Entity Framework and MS SQL Server. I've already created the database and set up the correct primary and foreign keys and relationships. I've created a .edmx model and imported two tables: Employee and Department. A department can have many employees and this relationship exists. I created a new controller called EmployeeController using the scaffolding options to create an API controller with read/write actions using Entity Framework. In the wizard, selected Employee as the model and the correct entity for the data context. The method that is created looks like this: // GET api/Employee public IEnumerable<Employee> GetEmployees() { var employees = db.Employees.Include(e => e.Department); return employees.AsEnumerable(); } When I call my API via /api/Employee, I get this error: ...The 'ObjectContent`1' type failed to serialize the response body for content type 'application/json; ...System.InvalidOperationException","StackTrace":null,"InnerException":{"Message":"An error has occurred.","ExceptionMessage":"Self referencing loop detected with type 'System.Data.Entity.DynamicProxies.Employee_5D80AD978BC68A1D8BD675852F94E8B550F4CB150ADB8649E8998B7F95422552'. Path '[0].Department.Employees'.","ExceptionType":"Newtonsoft.Json.JsonSerializationException","StackTrace":" ... Why is it self referencing [0].Department.Employees? That doesn't make a whole lot of sense. I would expect this to happen if I had circular referencing in my database but this is a very simple example. What could be going wrong?

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  • Slides and Code from “Using C#’s Async Effectively”

    - by Reed
    The slides and code from my talk on the new async language features in C# and VB.Net are now available on https://github.com/ReedCopsey/Effective-Async This includes the complete slide deck, and all 4 projects, including: FakeService: Simple WCF service to run locally and simulate network service calls. AsyncService: Simple WCF service which wraps FakeService to demonstrate converting sync to async SimpleWPFExample: Simplest example of converting a method call to async from a synchronous version AsyncExamples: Windows Store application demonstrating main concepts, pitfalls, tips, and tricks from the slide deck

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