Search Results

Search found 7676 results on 308 pages for 'linq extensions'.

Page 105/308 | < Previous Page | 101 102 103 104 105 106 107 108 109 110 111 112  | Next Page >

  • C# LINQ Where Predicate Type Arguments

    - by blu
    I have an XElement with values for mock data. I have an expression to query the xml: Expression<Func<XElement, bool>> simpleXmlFunction = b => int.Parse(b.Element("FooId").Value) == 12; used in: var simpleXml = xml.Elements("Foo").Where(simpleXmlFunction).First(); The design time error is: The type arguments for method 'System.Linq.Enumerable.Where(System.Collections.Generic.IEnumerable, System.Func)' cannot be inferred from the usage. Try specifying the type arguments explicitly' The delegate supplied to Where should take in an XElement and return a bool, marking if the item matches the query, I am not sure how to add anything more to the delegate or the where clause to mark the type. Also, the parallel method for the real function against the Entity Framework does not have this issue. What is not correct with the LINQ-to-XML version?

    Read the article

  • Would you use WCF Linq and JSON for an API

    - by Rico
    Ok Im building AN API but also wanting to have that API used by my own Application. I am pondering WCF, LinQ and JSON for my Webservices and Data and Silverlight for my application. I have a few questions. 1) would you recommend XML over JSON or Json over XML? a) is Json going to transfer and deserialize faster natively or is XML going to transfer and deserialize faster? 2) would Using LINQ hinder anyone connecting to my Service form PHP? 3) Would you recommend something different?

    Read the article

  • Tab Sweep: Primefaces3, @DataSourceDefinition, JPA Extensions, EclipseLink, Typed Query, Ajax, ...

    - by arungupta
    Recent Tips and News on Java, Java EE 6, GlassFish & more : • JSF2 + Primefaces3 + EJB3 & JPA2 Integration Project (@henk53) • The state of @DataSourceDefinition in Java EE (@henk53) • Java Persistence API (JPA) Extensions Reference for EclipseLink (EclipseLink) • JavaFX 2.2 Pie Chart with JPA 2.0 (John Yeary) • Typed Query RESTful Service Example (John Yeary) • How to set environment variables in GlassFish admin console (Jelastic) • Architect Enterprise Applications with Java EE (Oracle University) • Glassfish – Basic authentication (Marco Ghisellini) • Solving GlassFish 3.1/JSF PWC4011 warning (Rafael Nadal) • PrimeFaces AJAX Enabled (John Yeary)

    Read the article

  • How to Remove Extensions From, and Force the Trailing Slash at the End of URLs?

    - by Kronbernkzion
    Example of current file structure: example.com/foo.php example.com/bar.html example.com/directory/ example.com/directory/foo.php example.com/directory/bar.html example.com/cgi-bin/directory/foo.cgi I would like to remove HTML, PHP and CGI extensions from, and then force the trailing slash at the end of URLs. So, it could look like this: example.com/foo/ example.com/bar/ example.com/directory/ example.com/directory/foo/ example.com/directory/bar/ example.com/cgi-bin/directory/foo/ I am very frustrated because I've searched for 17 hours straight for solution and visited more than a few hundred pages on various blogs and forums. I'm not joking. So I think I've done my research. Here is the code that sits in my .htaccess file right now: RewriteCond %{REQUEST_FILENAME} !-d RewriteCond %{REQUEST_FILENAME}\.html -f RewriteRule ^(([^/]+/)*[^./]+)/$ $1.html RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteCond %{REQUEST_URI} !(\.[a-zA-Z0-9]|/)$ RewriteRule (.*)$ /$1/ [R=301,L] As you can see, this code only removes .html (and I'm not very happy with it because I think it could be done a lot simpler). I can remove the extension from PHP files when I rename them to .html through .htaccess, but that's not what I want. I want to remove it straight. This is the first thing I don't know how to do. The second thing is actually very annoying. My .htaccess file with code above, adds .html/ to every string entered after example.com/directory/foo/. So if I enter example.com/directory/foo/bar (obviously /bar doesn't exist since foo is a file), instead of just displaying message that page is not found, it converts it to example.com/directory/foo/bar.html/, then searches for a file for a few seconds and then displays the not found message. This, of course, is bad behavior. So, once again, I need the code in .htaccess to do the following things: Remove .html extension Remove .php extension Remove .cgi extension Force the trailing slash at the end of URLs Requests should behave correctly (no adding trailing slashes or extensions to strings if file or directory doesn't exist on server) Code should be as simple as possible I would very much appreciate any help. And to first person that gives me the solution, I'll send two $50 iTunes Store gift cards for US store. If this offends anyone, I am truly sorry and I apologize. Thanks in advance.

    Read the article

  • Tutoriel OpenGL Moderne : les extensions OpenGL, comprenez comment fonctionne l'ajout de fonctionnalités dans OpenGL 3 et supérieur

    Bonjour à tous,La rubrique 2D/3D/Jeux est heureuse de vous présenter une la suite de la série de tutoriels consacrée à OpenGL moderne (les versions à partir d'OpenGL 3.3). Ces tutoriels vous permettront d'intégrer facilement les nouveaux concepts d'OpenGL afin de profiter au maximum des dernières technologies de vos cartes graphiques. Ce douzième tutoriel vous informera sur ce que sont les extensions dans OpenGL et comment elles fonctionnent.Bonne lecture.

    Read the article

  • Listview of items from a object selected in another listview

    - by Ingó Vals
    Ok the title maybe a little confusing. I have a database with the table Companies wich has one-to-many relotionship with another table Divisions ( so each company can have many divisions ) and division will have many employees. I have a ListView of the companies. What I wan't is that when I choose a company from the ListView another ListView of divisions within that company appears below it. Then I pick a division and another listview of employees within that division appaers below that. You get the picture. Is there anyway to do this mostly inside the XAML code declaritively (sp?). I'm using linq so the Company entity objects have a property named Division wich if I understand linq correctly should include Division objects of the divisions connected to the company. So after getting all the companies and putting them as a itemsource to CompanyListView this is where I currently am. <ListView x:Name="CompanyListView" DisplayMemberPath="CompanyName" Grid.Row="0" Grid.Column="0" /> <ListView DataContext="{Binding ElementName=CompanyListView, Path=SelectedItem}" DisplayMemberPath="Division.DivisionName" Grid.Row="1" Grid.Column="0" /> I know I'm way off but I was hoping by putting something specific in the DataContext and DisplayMemberPath I could get this to work. If not then I have to capture the Id of the company I guess and capture a select event or something. Another issue but related is the in the seconde column besides the lisview I wan't to have a details/edit view for the selected item. So when only a company is selected details about that will appear then when a division under the company is picked It will go there instead, any ideas?

    Read the article

  • XElement.Load("~/App_Data/file.xml") Could not find a part of the path

    - by mahdiahmadirad
    hi everybody, I am new in LINQtoXML. I want to use XElement.Load("") Method. but the compiler can't find my file. can you help me to write correct path for my XML file? Note that: I defined a Class in App_Code and I want to use the XML file data in one of methods and my XML file Located in App_Data. settings = XElement.Load("App_Data/AppSettings.xml"); i cant Use Request.ApplicationPath and Page.MapPath() or Server.MapPath() to get the physical path for my file because i am not in a class Inherited form Page class. Brief error Message: *Could not find a part of the path 'C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE\App_Data\AppSettings.xml'*. you see the path compiled is fully different from my project path(G:\MyProjects\ASP.net Projects\VistaComputer\Website\App_Data\AppSettings.xml) Full error Message is here: System.IO.DirectoryNotFoundException was unhandled by user code Message="Could not find a part of the path 'C:\\Program Files\\Microsoft Visual Studio 9.0\\Common7\\IDE\\App_Data\\AppSettings.xml'." Source="mscorlib" StackTrace: at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy) at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize) at System.Xml.XmlDownloadManager.GetStream(Uri uri, ICredentials credentials) at System.Xml.XmlUrlResolver.GetEntity(Uri absoluteUri, String role, Type ofObjectToReturn) at System.Xml.XmlReader.Create(String inputUri, XmlReaderSettings settings, XmlParserContext inputContext) at System.Xml.XmlReader.Create(String inputUri, XmlReaderSettings settings) at System.Xml.Linq.XElement.Load(String uri, LoadOptions options) at System.Xml.Linq.XElement.Load(String uri) at ProductActions.Add(Int32 catId, String title, String price, String website, String shortDesc, String fullDesc, Boolean active, Boolean editorPick, String fileName, Stream image) in g:\MyProjects\ASP.net Projects\VistaComputer\Website\App_Code\ProductActions.cs:line 67 at CMS_Products_Operations.Button1_Click(Object sender, EventArgs e) in g:\MyProjects\ASP.net Projects\VistaComputer\Website\CMS\Products\Operations.aspx.cs:line 72 at System.Web.UI.WebControls.Button.OnClick(EventArgs e) at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) InnerException:

    Read the article

  • LinqToSql - Parallel - DataContext and Parallel

    - by Gregoire
    In .NET 4 and multicore environment, does the linq to sql datacontext object take advantage of the new parallels if we use DataLoadOptions.LoadWith? EDIT I know linq to sql does not parallelize ordinary queries. What I want to know is when we specify DataLoadOption.LoadWith, does it use parallelization to perform the match between each entity and its sub entities? Example: using(MyDataContext context = new MyDataContext()) { DataLaodOptions options =new DataLoadOptions(); options.LoadWith<Product>(p=>p.Category); return this.DataContext.Products.Where(p=>p.SomeCondition); } generates the following sql: Select Id,Name from Categories Select Id,Name, CategoryId from Products where p.SomeCondition when all the products are created, will we have a categories.ToArray(); Parallel.Foreach(products, p => { p.Category == categories.FirstOrDefault(c => c.Id == p.CategoryId); }); or categories.ToArray(); foreach(Product product in products) { product.Category = categories.FirstOrDefault(c => c.Id == product.CategoryId); } ?

    Read the article

  • Custom RoleProvider: Can't insert record in UsersInRole Table

    - by mahr.g.mohyuddin
    Hi, I have implemented a LINQ to SQL based RoleProvider, when I assign role to a user following exception is thrown while AddUsersToRoles method is called. I have defined a composite primary key userid & roleId on this table, it still throwing this exception: Can't perform Create, Update or Delete operations on 'Table(UsersInRole)' because it has no primary key. My LinQ to SQL implementation of AddUsersToRoles method is as follows. It breaks at db.UsersInRoles.InsertOnSubmit(userInRole); using (RussarmsDataContext db = new RussarmsDataContext()) { List<UsersInRole> usersInRole = new List<UsersInRole>(); foreach (string username in usernames) { foreach (string rolename in rolenames) { UsersInRole userInRole = new UsersInRole(); object userId = ProvidersUtility.GetUserIdByUserName(username,applicationName); object roleId = ProvidersUtility.GetRoleIdByRoleName(rolename,applicationName); if (userId != null && roleId != null) { userInRole.UserId = (Guid)userId; userInRole.RoleId = (Guid)roleId; db.UsersInRoles.InsertOnSubmit(userInRole); } } } try { // db.UsersInRoles.InsertAllOnSubmit(usersInRole); db.SubmitChanges(); } catch (ChangeConflictException) { db.ChangeConflicts.ResolveAll(RefreshMode.OverwriteCurrentValues); db.SubmitChanges(); } } Any help will be appreciated. Thanks.

    Read the article

  • Cross join (pivot) with n-n table containing values

    - by Styx31
    I have 3 tables : TABLE MyColumn ( ColumnId INT NOT NULL, Label VARCHAR(80) NOT NULL, PRIMARY KEY (ColumnId) ) TABLE MyPeriod ( PeriodId CHAR(6) NOT NULL, -- format yyyyMM Label VARCHAR(80) NOT NULL, PRIMARY KEY (PeriodId) ) TABLE MyValue ( ColumnId INT NOT NULL, PeriodId CHAR(6) NOT NULL, Amount DECIMAL(8, 4) NOT NULL, PRIMARY KEY (ColumnId, PeriodId), FOREIGN KEY (ColumnId) REFERENCES MyColumn(ColumnId), FOREIGN KEY (PeriodId) REFERENCES MyPeriod(PeriodId) ) MyValue's rows are only created when a real value is provided. I want my results in a tabular way, as : Column | Month 1 | Month 2 | Month 4 | Month 5 | Potatoes | 25.00 | 5.00 | 1.60 | NULL | Apples | 2.00 | 1.50 | NULL | NULL | I have successfully created a cross-join : SELECT MyColumn.Label AS [Column], MyPeriod.Label AS [Period], ISNULL(MyValue.Amount, 0) AS [Value] FROM MyColumn CROSS JOIN MyPeriod LEFT OUTER JOIN MyValue ON (MyValue.ColumnId = MyColumn.ColumnId AND MyValue.PeriodId = MyPeriod.PeriodId) Or, in linq : from p in MyPeriods from c in MyColumns join v in MyValues on new { c.ColumnId, p.PeriodId } equals new { v.ColumnId, v.PeriodId } into values from nv in values.DefaultIfEmpty() select new { Column = c.Label, Period = p.Label, Value = nv.Amount } And seen how to create a pivot in linq (here or here) : (assuming MyDatas is a view with the result of the previous query) : from c in MyDatas group c by c.Column into line select new { Column = line.Key, Month1 = line.Where(l => l.Period == "Month 1").Sum(l => l.Value), Month2 = line.Where(l => l.Period == "Month 2").Sum(l => l.Value), Month3 = line.Where(l => l.Period == "Month 3").Sum(l => l.Value), Month4 = line.Where(l => l.Period == "Month 4").Sum(l => l.Value) } But I want to find a way to create a resultset with, if possible, Month1, ... properties dynamic. Note : A solution which results in a n+1 query : from c in MyDatas group c by c.Column into line select new { Column = line.Key, Months = from l in line group l by l.Period into period select new { Period = period.Key, Amount = period.Sum(l => l.Value) } }

    Read the article

  • LinqKit System.InvalidCastException When Invoking method-provided expression on member property.

    - by mdworkin
    Given a simple parent/child class structure. I want to use linqkit to apply a child lambda expression on the parent. I also want the Lambda expression to be provided by a utility method. public class Foo { public Bar Bar { get; set; } } public class Bar { public string Value { get; set; } public static Expression<Func<Bar, bool>> GetLambdaX() { return c => c.Value == "A"; } } ... Expression<Func<Foo, bool>> lx = c => Bar.GetLambdaX().Invoke(c.Bar); Console.WriteLine(lx.Expand()); The above code throws System.InvalidCastException: Unable to cast object of type 'System.Linq.Expressions.MethodCallExpression' to type 'System.Linq.Expressions.LambdaExpression'. at LinqKit.ExpressionExpander.VisitMethodCall(MethodCallExpression m) at LinqKit.ExpressionVisitor.Visit(Expression exp) at LinqKit.ExpressionVisitor.VisitLambda(LambdaExpression lambda) at LinqKit.ExpressionVisitor.Visit(Expression exp) at LinqKit.Extensions.Expand<TDelegate>(Expression`1 expr) .... Please help!

    Read the article

  • Problem with .Contains

    - by Rene
    Hello there, I have a little problem which i can't solve. I want to use an SQL-In-Statement in Linq. I've read in this Forum and in other Forums that I have to use the .Contains (with reverse-thinking-notation :-)). As input i have a List of Guids. I first copied them into an array and then did something like that : datatoget = (from p in objectContext.MyDataSet where ArrayToSearch.Contains(p.Subtable.Id.ToString()) select p).ToList(); datatoget is the result in which all records matching the Subtable.Id (which is a Guid) should be stored. Subtable is a Detail-Table from MyData, and the Id is a Guid-Type. I've tried several things (Convert Guid to String, and then using .Contains, etc), but I always get an Exception which says : 'Linq to Entities' doesn't recognize the Method 'Boolean Contains(System.Guid) and is not able to Translate this method into a memory expression. (Something like that, because I'm using the German Version of VS2008) I am using L2E with .NET 3.5 and am programming in C# with VS 2008. I've read several Examples, but it doesn't work. Is it perhaps because of using Guid's instead of strings ? I've also tried to write my own compare-function, but I don't know how to integrate it so that .NET calls my function for comparing.

    Read the article

  • Entity Framework 4 / POCO - Where to start?

    - by Basiclife
    Hi, I've been programming for a while and have used LINQ-To-SQL and LINQ-To-Entities before (although when using entities it has been on a Entity/Table 1-1 relationship - ie not much different than L2SQL) I've been doing a lot of reading about Inversion of Control, Unit of Work, POCO and repository patterns and would like to use this methodology in my new applications. Where I'm struggling is finding a clear, concise beginners guide for EF4 which doesn't assume knowledge of EF1. The specific questions I need answered are: Code first / model first? Pros/cons in regards to EF4 (ie what happens if I do code first, change the code at a later date and need to regenerate my DB model - Does the data get preserved and transformed or dropped?) Assuming I'm going code-first (I'd like to see how EF4 converts that to a DB schema) how do I actually get started? Quite often I've seen articles with entity diagrams stating "So this is my entity model, now I'm going to ..." - Unfortunately, I'm unclear if they're created the model in the designer, saved it to generate code then stopped any further auto-code generation -or- They've coded (POCO)? classes and the somehow imported them into the deisgner view? I suppose what I really need is an understanding of where the "magic" comes from and how to add it myself if I'm not just generating an EF model directly from a DB. I'm aware the question is a little vague but I don't know what I don't know - So any input / correction / clarification appreciated. Needless to say, I don't expect anyone to sit here and teach me EF - I'd just like some good tutorials/forums/blogs/etc. for complete entity newbies Many thanks in advance

    Read the article

  • How to find unique values in jagged array

    - by David Liddle
    I would like to know how I can count the number of unique values in a jagged array. My domain object contains a string property that has space delimitered values. class MyObject { string MyProperty; //e.g = "v1 v2 v3" } Given a list of MyObject's how can I determine the number of unique values? The following linq code returns an array of jagged array values. A solution would be to store a temporary single array of items, looped through each jagged array and if values do not exist, to add them. Then a simple count would return the unique number of values. However, was wondering if there was a nicer solution. db.MyObjects.Where(t => !String.IsNullOrEmpty(t.MyProperty)) .Select(t => t.Categories.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries)) .ToArray() Below is a more readable example: array[0] = { "v1", "v2", "v3" } array[1] = { "v1" } array[2] = { "v4", "v2" } array[3] = { "v1", "v5" } From all values the unique items are v1, v2, v3, v4, v5. The total number of unique items is 5. Is there a solution, possibly using linq, that returns either only the unique values or returns the number of unique values?

    Read the article

  • XDocument.Parse fails due to resolution error, how to disable resolution

    - by Frank Krueger
    I am trying to parse the contents of http://feeds.feedburner.com/riabiz using XDocument.Parse(string) (because it gets cached in a DB.) However, it keeps failing with the below stack trace when it tries to resolve some URIs in that XML. I don't care about validation or any of that XML nonsense, I just want the structure parsed. How can I use XDocument without this URI resolution? System.ArgumentException: The specified path is not of a legal form (empty). at System.IO.Path.InsecureGetFullPath (System.String path) [0x00000] in :0 at System.IO.Path.GetFullPath (System.String path) [0x00000] in :0 at System.Xml.XmlResolver.ResolveUri (System.Uri baseUri, System.String relativeUri) [0x00000] in :0 at System.Xml.XmlUrlResolver.ResolveUri (System.Uri baseUri, System.String relativeUri) [0x00000] in :0 at Mono.Xml2.XmlTextReader.ReadStartTag () [0x00000] in :0 at Mono.Xml2.XmlTextReader.ReadContent () [0x00000] in :0 at Mono.Xml2.XmlTextReader.Read () [0x00000] in :0 at System.Xml.XmlTextReader.Read () [0x00000] in :0 at Mono.Xml.XmlFilterReader.Read () [0x00000] in :0 at Mono.Xml.XmlFilterReader.Read () [0x00000] in :0 at System.Xml.XmlReader.ReadEndElement () [0x00000] in :0 at System.Xml.Linq.XElement.LoadCore (System.Xml.XmlReader r, LoadOptions options) [0x00000] in :0 at System.Xml.Linq.XNode.ReadFrom (System.Xml.XmlReader r, LoadOptions options) [0x00000] in :0 ...

    Read the article

  • 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...

    Read the article

  • Problems finding classes in namespace and testing extend expected parent

    - by Matt
    So I am in the process of building a site in ASP.Net MVC, and in the process I am adding certain things to my Site.Master I want to make sure that all of my model classes extend a certain base class that contains all of the pieces the Site.Master needs to be operable. I want to test to make sure this assumption isn't broken (I believe this will save me time when I forget about it and can't figure out why a new combination isn't working.) I wrote a test that I thought would help with this, but I am running into two problems. First it isn't finding the one example model class I have so far in the LINQ call all of a sudden, I am admittedly still a bit new to LINQ. Second, I had it finding the class earlier, but I couldn't get it to verify that the class inherits from the base class. Here is the example test. [Test] public void AllModelClassesExtendAbstractViewModel() { var abstractViewModelType = typeof (AbstractViewModel); Assembly baseAssembly = Assembly.GetAssembly(abstractViewModelType); var modelTypes = baseAssembly.GetTypes() .Where(assemblyType => (assemblyType.Namespace.EndsWith("Models") && assemblyType.Name != "AbstractViewModel")) .Select(assemblyType => assemblyType); foreach (var modelType in modelTypes) { Assert.That(modelType.IsSubclassOf(abstractViewModelType), Is.True , modelType.Name + " does not extend AbstractViewModel"); } }

    Read the article

  • How can you pre-define a variable that will contain an anonymous type?

    - by HitLikeAHammer
    In the simplified example below I want to define result before it is assinged. The linq queries below return lists of anonymous types. result will come out of the linq queries as an IEnumerable<'a but I can't define it that way at the top of the method. Is what I am trying to do possible (in .NET 4)? bool large = true; var result = new IEnumerable(); //This is wrong List<int> numbers = new int[]{1,2,3,4,5,6,7,8,9,10}.ToList<int>(); if (large) { result = from n in numbers where n > 5 select new { value = n }; } else { result = from n in numbers where n < 5 select new { value = n }; } foreach (var num in result) { Console.WriteLine(num.value); } EDIT: To be clear I know that I do not need anonymous types in the example above. It is just to illustrate my question with a small, simple example.

    Read the article

  • 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.

    Read the article

  • Where do objects merge/join data in a 3-tier model?

    - by BerggreenDK
    Its probarbly a simple 3-tier problem. I just want to make sure we use the best practice for this and I am not that familiary with the structures yet. We have the 3 tiers: GUI: ASP.NET for Presentation-layer (first platform) BAL: Business-layer will be handling the logic on a webserver in C#, so we both can use it for webforms/MVC + webservices DAL: LINQ to SQL in the Data-layer, returning BusinessObjects not LINQ. DB: The SQL will be Microsoft SQL-server/Express (havent decided yet). Lets think of setup where we have a database of [Persons]. They can all have multiple [Address]es and we have a complete list of all [PostalCode] and corresponding citynames etc. The deal is that we have joined a lot of details from other tables. {Relations}/[tables] [Person]:1 --- N:{PersonAddress}:M --- 1:[Address] [Address]:N --- 1:[PostalCode] Now we want to build the DAL for Person. How should the PersonBO look and when does the joins occure? Is it a business-layer problem to fetch all citynames and possible addressses pr. Person? or should the DAL complete all this before returning the PersonBO to the BAL ? Class PersonBO { public int ID {get;set;} public string Name {get;set;} public List<AddressBO> {get;set;} // Question #1 } // Q1: do we retrieve the objects before returning the PersonBO and should it be an Array instead? or is this totally wrong for n-tier/3-tier?? Class AddressBO { public int ID {get;set;} public string StreetName {get;set;} public int PostalCode {get;set;} // Question #2 } // Q2: do we make the lookup or just leave the PostalCode for later lookup? Can anyone explain in what order to pull which objects? Constructive criticism is very welcome. :o)

    Read the article

  • How can I have 2 ADO access methods use the same Transaction?

    - by KevinDeus
    I'm writing a test to see if my LINQ to Entity statement works.. I'll be using this for others if I can get this concept going.. my intention here is to INSERT a record with ADO, then verify it can be queried with LINQ, and then ROLLBACK the whole thing at the end. I'm using ADO to insert because I don't want to use the object or the entity model that I am testing. I figure that a plain ADO INSERT should do fine. problem is.. they both use different types of connections. is it possible to have these 2 different data access methods use the same TRANSACTION so I can roll it back?? _conn = new SqlConnection(_connectionString); _conn.Open(); _trans = _conn.BeginTransaction(); var x = new SqlCommand("INSERT INTO Table1(ID, LastName, FirstName, DateOfBirth) values('127', 'test2', 'user', '2-12-1939');", _conn); x.ExecuteNonQuery(); //So far, so good. Adding a record to the table. //at this point, we need to do **_trans.Commit()** here because our Entity code can't use the same connection. Then I have to manually delete in the TestHarness.TearDown.. I'd like to eliminate this step //(this code is in another object, I'll include it for brevity. Imagine that I passed the connection in) //check to see if it is there using (var ctx = new XEntities(_conn)) //can't do this.. _conn is not an EntityConnection! { var retVal = (from m in ctx.Table1 where m.first_name == "test2" where m.last_name == "user" where m.Date_of_Birth == "2-12-1939" where m.ID == 127 select m).FirstOrDefault(); return (retVal != null); } //Do test.. Assert.BlahBlah(); _trans.Rollback();

    Read the article

  • odd nullreference error at foreach when rendering view

    - by giddy
    This error is so weird I Just can't really figure out what is really wrong! In UserController I have public virtual ActionResult Index() { var usersmdl = from u in RepositoryFactory.GetUserRepo().GetAll() select new UserViewModel { ID = u.ID, UserName = u.Username, UserGroupName = u.UserGroupMain.GroupName, BranchName = u.Branch.BranchName, Password = u.Password, Ace = u.ACE, CIF = u.CIF, PF = u.PF }; if (usersmdl != null) { return View(usersmdl.AsEnumerable()); } return View(); } My view is of type @model IEnumerable<UserViewModel> on the top. This is what happens: Where and what exactly IS null!? I create the users from a fake repository with moq. I also wrote unit tests, which pass, to ensure the right amount of mocked users are returned. Maybe someone can point me in the right direction here? Top of the stack trace is : at lambda_method(Closure , User ) at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext() at ASP.Index_cshtml.Execute() Is it something to do with linq here? Tell me If I should include the full stack trace.

    Read the article

  • Applying correct bindings to WPF datatemplate to maximize reusability

    - by johncatfish
    Hi. I have a WPF application. I want to apply that datatemplate to a Listbox filled with records from Table02. Then, for each listboxitem I need to bind the combobox to the same database table (Table01), but for each listboxitem the selected item will vary. It will be a foreign key to Table01. <DataTemplate x:Key="Table01DataTemplate"> <Grid> <ComboBox ItemsSource="{Binding Model.IQueryable_Table01, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}" SelectedValue="{Binding Table01_ForeignKey}" DisplayMemberPath="name" SelectedValuePath="id" /> <!-- Other stuff --> </Grid> </DataTemplate> <ListBox x:Name="lbTest" ItemTemplate="{StaticResource Table01DataTemplate}" /> <!-- In .cs file lbTest.DataContext = this; --> Notes: Model.IQueryable_Table01 is a property which encapsulates a Linq-to-sql call returning a IQueryable. lbTest will be filled by setting ItemsSource with a Linq-to-sql call. Is this a good way to do the bindings in a data template for a maximum reusability? I also thought of replacing AncestorType={x:Type Window} with lbTest.DataContext = this; AncestorType={x:Type Application} and lbTest.DataContext = App.Current; But it didn't work (Exception on loading) and I don't know if there's any caveats or down-sides to this approach. Is this good? Any suggestions or improvements? Thanks.

    Read the article

  • Problem with inheritance and List<>

    - by Jagd
    I have an abstract class called Grouping. I have a subclass called GroupingNNA. public class GroupingNNA : Grouping { // blah blah blah } I have a List that contains items of type GroupingNNA, but is actually declared to contain items of type Grouping. List<Grouping> lstGroupings = new List<Grouping>(); lstGroupings.Add( new GroupingNNA { fName = "Joe" }); lstGroupings.Add( new GroupingNNA { fName = "Jane" }); The Problem: The following LINQ query blows up on me because of the fact that lstGroupings is declared as List< Grouping and fName is a property of GroupingNNA, not Grouping. var results = from g in lstGroupings where r.fName == "Jane" select r; Oh, and this is a compiler error, not a runtime error. Thanks in advance for any help on this one! More Info: Here is the actual method that won't compile. The OfType() fixed the LINQ query, but the compiler doesn't like the fact that I'm trying to return the anonymous type as a List< Grouping. private List<Grouping> ApplyFilterSens(List<Grouping> lstGroupings, string fSens) { // This works now! Thanks @Lasse var filtered = from r in lstGroupings.OfType<GroupingNNA>() where r.QASensitivity == fSens select r; if (filtered != null) { **// Compiler doesn't like this now** return filtered.ToList<Grouping>(); } else return new List<Grouping>(); }

    Read the article

  • Visual Studio 2010 Extension Manager crashes

    - by Alexey
    After installing a bunch of extensions to try out I restarted VS 2010 and it started crashing. Unfortunately, it consistently crashes when opening Tools | Extension Manager. Any ideas how to fix and avoid a complete uninstall/reinstall? Event log has this: Application: devenv.exe Framework Version: v4.0.30319 Description: The process was terminated due to an unhandled exception. Exception Info: System.AggregateException Stack: at System.Threading.Tasks.TaskExceptionHolder.Finalize()

    Read the article

< Previous Page | 101 102 103 104 105 106 107 108 109 110 111 112  | Next Page >