I'm refactoring this code and was trying to think of a simple linq expression to populate this Dictionary. IEnumerable<IHeaderRecord> headers = PopulateHeaders(); var headerLocationLookup = new Dictionary<string, IHeaderRecord>(); foreach (var header in headers) { //destination locations can repeat, if they do, dictionary should only ...
I've got a situation where I need to prefetch some entities through a many-to-many relationship. So it's like the classic BlogPost <- BlogPostTag -> Tag situation. Yes, I'm aware of LoadOptions but I can't use it because it's a web application and I'm using the one datacontext per request pattern. It also seems you can't use projection...
I'm trying to figure out a way to allow users of my application to define their own queries or filters that can be applied to a collection. I want to eventually provide an intuitive user interface to create these filters (see image below), but initial it would be OK if a user had to type of a text query string. I'll also need to be able ...
I tried to use linq but failed because i have no xml knowledge. What is the easiest way to get the id or link and updated from an rss feed? (an example feed -> http://stackoverflow.com/feeds/question/1926343) I have no idea how to skip all elements until the first entry element. I also dont know how to pull each link and data from each...
I have a bunch of rows grouped on an attribute called MyID. Now I want the one row from each group where the StatusDate attribute is the highest in that one group. This is what I've come up with. rows.Select(x => x.Where(y => y.StatusDate == x.Max(z => z.StatusDate)).First()) With a bit more explanation: rows.Select(x => // x is a g...
Hi all, I have this code. How can I check null values for SingleOrDefault method ?? public static List<ETY.Rol> GetRolesByApplicationAndCompany(this UsuarioContext usuario, int company, int app) { List<ETY.Company> lCompanies= usuario.Companies; var roles = lCompanies. SingleOrDefault(e ...
I have a solution "Foo" with 2 projects. "FooCore" and "FooWeb" where FooCore peoject contains the FooDatacontext in namespace Foo.FooCore.Core.Domain . How can bind the datacontext with linqdatasource in FooWeb project in aspx page. Is this possible by doing "<% Import Namespace="Foo.FooCore.Core.Domain"%>" in that aspx page? I hope I a...
Hi - I am trying to read an XML file using LINQ. I have had no problem reading and parsing simple XML files but this one has me stumped. Here is a portion of the file: The file is properly formed and valid. <Activities> <Activity Sport="Other"> <Id>2009-12-17T19:53:14Z</Id> <Lap StartTime="2009-12-17T19:53:14Z"> ...
if you have a select LINQ query that should only return one result, do you have to have a foreach loop to get the result? Or is there a better way? ...
I have 2 lists and I need to combine the joining values from A and B, but also include the values from A and B that don't match the join. class TypeA { public string Key { get; set; } public int ValueA { get; set; } } class TypeB { public string Key { get; set; } public int ValueB { get; set; } } class TypeAB { pub...
Note this question is similar this one except I'm not working with linq-to-sql, so the "let" is not usable. Basically I have a select of the type ... .Select(c => new SampleClass { Id = c.Location.Name, Name = c.Location.Name }).Distinct().ToList() which used to work when I just had ... .Select(c => c.Location.Name).Distinct().ToLis...
Hi Folks, i've got the following code, which compiles but doesn't retrieve the correct results. I'm trying to retrieve all the Banned log entries for people who have been recorded at cheating on a gaming server. The database (in this case, two IList tables) has two simple tables. GameFiles : the game which has a log file .. which w...
Can anyone help explain why when I bind the following code to a gridview, the negative numbers come out as 0.00? var shoppingCartItems2 = Checkout.GetPropertyListingShoppingCartItems(SC.ShoppingCartID); var columns = from sci in shoppingCartItems2 select new { Description = sci.ShoppingCartItemType...
Let say I got the following code in my SqlUserRepository : var user = from u in NHibernateLinqContext.Linq<User>() ... What I would like is to have a similar context for my FakeuserRepository var user = from u in FakeLinqContext.Linq<User>() ... Like that, I'll be able to use the same logic in my SqlUserRespository that my FakeUser...
I'm trying to write Linq-To-SQL queries in LinqPad to help migrate users from old tables to new tables. Part of this migration is storing all addresses in a separate table. I'm using the following query to determine if a user's address exists in the new table (so I don't have duplicate entries): var addresses = from a in Addresses where...
How to cast System.Data.Linq.Table to System.Data.DataTable DemoDBDataContext context = new DemoDBDataContext(); DataSet ds = new DataSet(); var query = context.Customers; ds.Tables[0] = query; How to do that? the assignment ds.Tables[0] = query; It throws Property or indexer 'Sys...
List<byte[]> data = new List<string>(File.ReadAllLines(Filename)).ConvertAll<byte[]>(delegate(string value) { return new List<string>(value.Split('.')).ConvertAll<byte>(delegate(string byteVal) { return Convert.ToByte(byteVal); }).ToArray(); }); ...
This question is a follow on to link text hence the revisited in the title. I raise this as a new question as the accepted answer and comment made under the original question both suggest that the equals keyword used in the join query refers to only value types within the comparison. I believe this is misleading as follows. Behind the s...
Hi, can someone explain how the LINQ functions Where(..) and FindAll(..) differ? they both seem to do the same thing.... ...
Hello, How to convert the nested hierarchical object to flatten objects by using LINQ? I know that we can easily use foreach loop to achieve that. But I'm wondering if there is a way to write it in LINQ. class Person{ public int ID {get;set} public string Name {get;set} public List<Person> Name {get;} } Data : ID : 1 Nam...