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  • Converting XDocument to XmlDocument and vice versa.

    - by Workshop Alex
    It's a very simple problem that I have. I use XDocument to generate an XML file. I then want to return it as a XmlDocument class. And I have an XmlDocument variable which I need to convert back to XDocument to append more nodes. So, what is the most efficient method to convert XML between XDocument and XmlDocument? (Without using any temporary storage in a file.)

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  • Linq2Sql Best Practices

    - by this. __curious_geek
    I'm recently migrating to Linq2Sql and all my future projects will be using Linq2Sql. Having said that, I researched a lot on how to properly plug-in Linq2Sql in application design. what to put at what layer ? How do you design your repositories and business layer services ? Should I use DTOs over Linq2Sql entities on interaction layer ? what things should I be careful about ? what problems did you face ? I did not find any rock-solid material that really talked about one single thing and everyone have their own opinions. I'm looking forward to your ideas on how to integrate/use Linq2Sql in projects. My priority is maintenance[it should be maintenable and when multiple people work on same project] and scalabilty [it should have scope of evolution]. Thanks.

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  • Validation L2S question

    - by user158020
    This may be a bit winded because I am new to wpf. I have created a partial class for an entity in my L2S class that is primarily used for validation. It implements the onchanging and onvalidate methods. I am trying to use the MVVM pattern, and in a window/view I have set the datacontext in the xaml: <Window.DataContext> <vm:StartViewModel /> </Window.DataContext> when a user leaves a required field in the view blank, the onchanging event of the partial class is fired when I close the form, not when I save the data. So, if a user leaves the textbox blank, the old value is retained and the onchaging method is fired, but I have no idea how to alert the user of the resulting error. here is my onchanging code in the partial class: partial void Ondocument_titleChanging(string value) { if (value.Length == 0) throw new Exception("Document title is required."); if (value.Length > 256) throw new Exception("Document title cannot be longer than 256 characters."); } throwing an exception doesn't notify the user of the error. it just allows the form to close and rejects the changes to the textbox. hope this makes sense... edit: this example was taken from Scott Guthries article here: http://aspalliance.com/1427_LINQ_to_SQL_Part_5__Binding_UI_using_the_ASPLinqDataSource_Control.5

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  • Type casting in TPC inheritance

    - by Mohsen Esmailpour
    I have several products like HotelProduct, FlightProduct ... which derived from BaseProduct class. The table of these products will be generated in TPC manner in database. There is OrderLine class which has a BaseProduct. My problem is when i select an OrderLine with related product i don't know how cast BaseProduct to derived product. for example i have this query: var order = (from odr in _context.Orders join orderLine in _context.OrderLines on odr.Id equals orderLine.OrderId join hotel in _context.Products.OfType<HotelProduct>() on orderLine.ProductId equals hotel.Id where odr.UserId == userId && odr.Id == orderId orderby odr.OrderDate descending select odr).SingleOrDefault(); In OrderLine i have BaseProduct properties not properties of HotelProduct. Is there any way to cast BaseProduct to derived class in OrderLine or any other solutions ?

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  • Getting error in MVC Proj while writing Lambda Expression

    - by Shrewd Demon
    hi, i am creating a sample movie (MVC) application. I was getting fine with Viewing and Creating a new record, but when i wrote the code to get the details of a particular record i met with the following error: Unable to cast objec`t of type 'System.Data.Objects.ObjectQuery`1[MovieApp.Models.Movie]' to type 'MovieApp.Model`s.Movie'. here is the code i wrote for getting the details public ActionResult Details(int id) { var moviedetail = (Movie)_entities.MovieSet.Where(mvid => mvid.Id == id); return View(moviedetail); } can any body tell me whats going wrong and where ?? thank you.

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  • "ref" vs "out" keyword errors using the sql-net and C# Sqlite combination for windows phone 7.1

    - by param
    I am getting some "ref" vs "out" keyword errors using the sql-net and C# Sqlite combination for windows phone 7.1. Is this due to a wrong combination of libraries that I am using? App Type: Windows Phone 7.1 Using: 1) sql-net Version 1.0.5, Source Nuget thru Visual Studio 2) C# Sqlite for WP7 (wp7sqlite) ( Community.CSharpSqlite.WP7) Version 0.1.1, Source Nuget thru Visual Studio. The exact error I receive is below **Error 5 The best overloaded method match for Community.CsharpSqlite.Sqlite3.sqlite3_open(string, ref Community.CsharpSqlite.Sqlite3.sqlite3)' has some invalid arguments C:\Dev\Learning\SQLite.cs Line:2492 Column: 29 ** The next error then hints that it is related to the parameter being passed as "out" type instead of "ref" type. Error 6 Argument 2 must be passed with the 'ref' keyword C:\Dev\Learning\SQLite.cs Line: 2492 Column: 64 I can make the compile errors go away by replacing the "out" keyword with the "ref" keyword, but that is likely to lead to other issues. Given that I do not see much complain about this issue - I may be doing something wrong but not able to detect easily. Thanks, Parmeshwar

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  • ControlCollection extension method optimazation

    - by Johan Leino
    Hi, got question regarding an extension method that I have written that looks like this: public static IEnumerable<T> FindControlsOfType<T>(this ControlCollection instance) where T : class { T control; foreach (Control ctrl in instance) { if ((control = ctrl as T) != null) { yield return control; } foreach (T child in FindControlsOfType<T>(ctrl.Controls)) { yield return child; } } } public static IEnumerable<T> FindControlsOfType<T>(this ControlCollection instance, Func<T, bool> match) where T : class { return FindControlsOfType<T>(instance).Where(match); } The idea here is to find all controls that match a specifc criteria (hence the Func<..) in the controls collection. My question is: Does the second method (that has the Func) first call the first method to find all the controls of type T and then performs the where condition or does the "runtime" optimize the call to perform the where condition on the "whole" enumeration (if you get what I mean). secondly, are there any other optimizations that I can do to the code to perform better. An example can look like this: var checkbox = this.Controls.FindControlsOfType<MyCustomCheckBox>( ctrl => ctrl.CustomProperty == "Test" ) .FirstOrDefault();

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  • MVC Persist Collection ViewModel (Update, Delete, Insert)

    - by Riccardo Bassilichi
    In order to create a more elegant solution I'm curios to know your suggestion about a solution to persist a collection. I've a collection stored on DB. This collection go to a webpage in a viewmodel. When the go back from the webpage to the controller I need to persist the modified collection to the same DB. The simple solution is to delete the stored collection and recreate all rows. I need a more elegant solution to mix the collections and delete not present record, update similar records ad insert new rows. this is my Models and ViewModels. public class CustomerModel { public virtual string Id { get; set; } public virtual string Name { get; set; } public virtual IList<PreferredAirportModel> PreferedAirports { get; set; } } public class AirportModel { public virtual string Id { get; set; } public virtual string AirportName { get; set; } } public class PreferredAirportModel { public virtual AirportModel Airport { get; set; } public virtual int CheckInMinutes { get; set; } } // ViewModels public class CustomerViewModel { [Required] public virtual string Id { get; set; } public virtual string Name { get; set; } public virtual IList<PreferredAirporViewtModel> PreferedAirports { get; set; } } public class PreferredAirporViewtModel { [Required] public virtual string AirportId { get; set; } [Required] public virtual int CheckInMinutes { get; set; } } And this is the controller with not elegant solution. public class CustomerController { public ActionResult Save(string id, CustomerViewModel viewModel) { var session = SessionFactory.CurrentSession; var customer = session.Query<CustomerModel>().SingleOrDefault(el => el.Id == id); customer.Name = viewModel.Name; // How cai I Merge collections handling delete, update and inserts ? var modifiedPreferedAirports = new List<PreferredAirportModel>(); var modifiedPreferedAirportsVm = new List<PreferredAirporViewtModel>(); // Update every common Airport foreach (var airport in viewModel.PreferedAirports) { foreach (var custPa in customer.PreferedAirports) { if (custPa.Airport.Id == airport.AirportId) { modifiedPreferedAirports.Add(custPa); modifiedPreferedAirportsVm.Add(airport); custPa.CheckInMinutes = airport.CheckInMinutes; } } } // Remove common airports from ViewModel modifiedPreferedAirportsVm.ForEach(el => viewModel.PreferedAirports.Remove(el)); // Remove deleted airports from model var toDelete = customer.PreferedAirports.Except(modifiedPreferedAirports); toDelete.ForEach(el => customer.PreferedAirports.Remove(el)); // Add new Airports var toAdd = viewModel.PreferedAirports.Select(el => new PreferredAirportModel { Airport = session.Query<AirportModel>(). SingleOrDefault(a => a.Id == el.AirportId), CheckInMinutes = el.CheckInMinutes }); toAdd.ForEach(el => customer.PreferedAirports.Add(el)); session.Save(customer); return View(); } } My environment is ASP.NET MVC 4, nHibernate, Automapper, SQL Server. Thank You!!

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  • Which O/RM tool supports Microsofts Access?

    - by Steven
    For one of my clients I'm currently building an application that communicates with a legacy Microsoft Access database. Migrating to SQL server is unfortunately not (yet) an option. I currently write the queries using OleDbConnection, OleDbCommand and –good old- text based queries. As you can imagine I'm a bit spoiled by using modern O/RM tools and I feel like I went back in time. Which O/RM tool supports Microsoft Access so I can get rid of this uglyness?

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  • ASP.Net Gridview paging, pageindex always == 0.

    - by David Archer
    Hi all, Having a slight problem with my ASP.Net 3.5 app. I'm trying to get the program to pick up what page number has been clicked. I'm using ASP.Net's built in AllowPaging="True" function. It's never the same without code, so here it is: ASP.Net: <asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333" GridLines="Vertical" Width="960px" AllowSorting="True" EnableSortingAndPagingCallbacks="True" AllowPaging="True" PageSize="25" > <RowStyle BackColor="#F7F6F3" ForeColor="#333333" /> <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /> <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /> <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <EditRowStyle BackColor="#999999" /> <AlternatingRowStyle BackColor="White" ForeColor="#284775" /> </asp:GridView> C#: var fillTable = from ft in db.IncidentDatas where ft.pUserID == Convert.ToInt32(ClientList.SelectedValue.ToString()) select new { Reference = ft.pRef.ToString(), Date = ft.pIncidentDateTime.Value.Date.ToShortDateString(), Time = ft.pIncidentDateTime.Value.TimeOfDay, Premesis = ft.pPremises.ToString(), Latitude = ft.pLat.ToString(), Longitude = ft.pLong.ToString() }; if (fillTable.Count() > 0) { GridView1.DataSource = fillTable; GridView1.DataBind(); var IncidentDetails = fillTable.ToList(); for (int i = 0; i < IncidentDetails.Count(); i++) { int pageno = GridView1.PageIndex; int pagenostart = pageno * 25; if (i >= pagenostart && i < (pagenostart + 25)) { //Processing } } } Any idea why GridView1.PageIndex is always = 0? The thing is, the processing works correctly for the grid view.... it will always go to the correct paging page, but it's always 0 when I try to get the number. Help!

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  • How to return all records and whether a related record exists?

    - by David Glenn
    Using Entity Framework 4 CTP5 I have a basic model and a basic DbContext that works public class Customer { public int CustomerId { get; set; } public int Name { get; set; } //... public ICollection<Address> Addresses { get; set; } public bool HasAddress { get { return Addresses.Count > 0; } } } public class Address { public int AddressId { get; set; } public string StreetLine1 { get; set; } //.... public Customer Customer { get; set; } } How can I query my DbContext to return all customers and whether they have an address? A customer can have multiple addresses and I don't want to return all the addresses for each customer when I am only interested in whether they have an address or not. I use context.Customers.Include(c => c.Addresses) but that returns all addresses for each customer

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  • Put logic behind generated LinqToSql fields

    - by boris callens
    In a database I use throughout several projects, there is a field that should actually be a boolean but is for reasons nobody can explain to me a field duplicated over two tables where one time it is a char ('Y'/'N') and one time an int (1/0). When I generate a datacontext with LinqToSql the fields off course gets these datatypes. It would be nice if I don't have to drag this stupid choice of datatype throughout the rest of my application. Is there a way to give the generated classes a little bit of logic that just return me return this.equals('Y'); and return this==1; Preferably without having to make an EXTRA field in my partial class. It would be a solution to give the generated field a totally different name that can only be accessed through the partial class and then generate the extra field with the original name with my custom logic in the partial class. I don't know how to alter the accesibility level in my generated class though.. Any suggestions?

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  • retrivenewly inserted record ID with Linq2SQL

    - by devmania
    hi, i am using the following private BlogDataContext db = new BlogDataContext (); article.Created = DateTime.UtcNow; article.Modified = DateTime.UtcNow; db.Articles.InsertOnSubmit(article); db.SubmitChanges( ); int id = article.Id; i am wondering is this save, i mean will it give me the Id of the article user inserted or will there be case of concurrences if another user update the article in fraction of second of second after this user ? thanks in advanced.

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  • Expression.Call() to String.Equals() throws error

    - by Sam
    The following code: var constant = Expression.Constant("find me", typeof(string)); // memberExpression evaluates to a string var predicate = Expression.Call(memberExpression, "Equals", null, constant); is throwing the error More than one method 'Equals' on type 'System.String' is compatible with the supplied arguments. I'm guessing that's because there's Equals(Object) and Equals(String) - is there any way for me to specify which method I mean to use via the overload of Expression.Call() that takes an instance method name as a string? Or do I have to make a special case for calls to Equals() to take a MethodInfo instead?

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  • How can I create/update an XML node that may or may not exist?

    - by ScottBai
    Is there a method available (i.e. without me creating my own recursive method), for a given xpath (or other method of identifying the hierarchical position) to create/update an XML node, where the node would be created if it does not exist? This would need to create the parent node if it does not exist as well. I do have an XSD which includes all possible nodes. i.e. Before: <employee> <name>John Smith</name> </employee> Would like to call something like this: CoolXmlUpdateMethod("/employee/address/city", "Los Angeles"); After: <employee> <name>John Smith</name> <address> <city>Los Angeles</city> </address> </employee> Or even a method to create a node, given an xpath, wherein it will recursively create the parent node(s) if they do not exist? As far as the application (if it matters), this is taking an existing XML doc that contains only populated nodes, and adding data to it from another system. The new data may or may not already have values populated in the source XML. Surely this is not an uncommon scenario?

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  • Why does this code generate a NotSupportedException?

    - by edg
    This is fine string foo(string f) { return f; } string bar = foo(""); var item = (from f in myEntities.Beer where f.BeerName == bar select f).FirstOrDefault(); and this is fine string foo(string f) { return f; } string bar = ""; var items = from f in myEntities.Beer where f.BeerName == foo(bar) select f; So why does this throw System.NotSupportedException? string foo(string f) { return f; } string bar = ""; var item = (from f in myEntities.Beer where f.BeerName == foo(bar) select f).FirstOrDefault();

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  • The data types text and nvarchar are incompatible in the equal to operator

    - by metro
    Hi there. this is my code ProductController.cs public ActionResult Details(string id) { product productx = productDB.products.Single(pr => pr.Product1 == id); return View(productx); } Details.aspx <td> <%-- : Html.ActionLink("Edit", "Edit", new { id=item.Id }) % --> <%: Html.ActionLink("Details", "Details", new { id = item.Product1 })%> </td> this is what im using to list some products from a sql database, each product have a link to a Details page to show more informations about it what Im trying is to only put the product label in that link to let it show something like www.mysite.com\products\battery (not the id) I've imagined this should work, but it throw an The data types text and nvarchar are incompatible in the equal to operator. error and neither (pr => pr.Product1.Equals(id)); works the error is clear and Im asking how should I do to make it work this way ? thanks

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  • .Net Entity Framework & POCO ... querying full table problem

    - by Chris Klepeis
    I'm attempting to implement a repository pattern with my poco objects auto generated from my edmx. In my repository class, I have: IObjectSet<E> _objectSet; private IObjectSet<E> objectSet { get { if (_objectSet == null) { _objectSet = this._context.CreateObjectSet<E>(); } return _objectSet; } } public IQueryable<E> GetQuery(Func<E, bool> where) { return objectSet.Where(where).AsQueryable<E>(); } public IList<E> SelectAll(Func<E, bool> where) { return GetQuery(where).ToList(); } Where E is the one of my POCO classes. When I trace the database and run this: IList<Contact> c = contactRepository.SelectAll(r => r.emailAddress == "[email protected]"); It shows up in the sql trace as a select for everything in my Contact table. Where am I going wrong here? Is there a better way to do this? Does an objectset not lazy load... so it omitted the where clause? This is the article I read which said to use objectSet's... since with POCO, I do not have EntityObject's to pass into "E" http://devtalk.dk/CommentView,guid,b5d9cad2-e155-423b-b66f-7ec287c5cb06.aspx

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  • An analog of String.Join(string, string[]) for IEnumerable<T>

    - by abatishchev
    class String contains very useful method - String.Join(string, string[]). It creates a string from an array, separating each element of array with a symbol given. But general - it doesn't add a separator after the last element! I uses it for ASP.NET coding for separating with "<br />" or Environment.NewLine. So I want to add an empty row after each row in asp:Table. What method of IEnumerable<TableRow> can I use for the same functionality?

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  • XAttribute Generating strange namespaces

    - by Adam Driscoll
    I'm constructing an XElement with a couple attributes that have different namespaces. The code looks like this: var element = new XElement("SynchronousCommand", new XAttribute("{wcm}action", "add"), new XAttribute("{ns}id", Guid.NewGuid()), new XElement... ); The XML that is generated looks like this: <unattend xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="urn:schemas-microsoft-com:unattend"> <SynchronousCommand d5p1:action="add" d5p2:id="c0f5fc6d-d407-4d3d-8a05-d84236cca2fb" xmlns:d5p2="ns" xmlns:d5p1="wcm"> ... </SynchronousCommand> </unattend> I'm just wondering if the auto-generated d5p2 is valid and why it is doing this. According to the XML standards here it seems like it would be valid. But why is it not: <unattend xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="urn:schemas-microsoft-com:unattend"> <SynchronousCommand wcm:action="add" ns:id="c0f5fc6d-d407-4d3d-8a05-d84236cca2fb" > To generate the XML I'm doing this: public class unattend { public List<XElement> Any {get;} } var unattend = new unattend(); unattend.Add(element); serializer.Serialize(xmlWriter, unattend);

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  • How to efficiently handle Where and OrderBy clauses

    - by Goran
    My business layer passes all the required information to UI layer. From what I have read, in general, best practice is to send fetched data to UI layer, and to avoid passing queries like ObjectQuery. My problem with this approach is next: If I am to make a flexible business layer, then I should allow UI to sort the data anyway it requires. Fetching sorted data from database, and then resorting them in UI is kind of bad practice for me, so the only way is to somehow So what are my options? Is there a way to make it like this: public void OrderByMethod(params ...) { .... } so I can call it like this: OrderByMethod(MyEntity.Property1, MyEntity.Property2 descending....); Thanks, Goran

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