linq

Linq Query after Where statement not returning relationship data

public List<Store> GetAllFriendsTopStores(long uid, List<long> users) { using (var entities = new myEntities()) { var v = entities.DbUsers .Where( x => users.Contains( x.uid )) .Stores // i can't select stores here? Why is this??? } } In this case Stores is a navigation property... I need to be ...

this method cannot be translated into a store expression

I have a bunch of Linq to Entity methods that had the same select statement, so I thought I would be clever and separate that out into it's own method to reduce redundancy... but when i attempted to run the code, i got the following error... this method cannot be translated into a store expression Here is the method i created... ...

How to get "One -one" permutation string from a List<String> in C# using LINQ

I'm having a list of string List<String> MyList=new List<String>{ "A,B" , "C,D,E" , "F,G" }; I need to convert the List "MyList" into the following format "A-B" "B-A" "C-D" "C-E" "D-C" "D-E" "E-C" "E-D" "F-G" "G-F" Now i'm using something like spliting each item by "," and then adding that to a new list, then taking combination and...

Is there a LINQ syntax for the (T, int) overloads of Where and Select?

The query var q = from elem in collection where someCondition(elem) select elem; translates to var q = collection.Where(elem => someCondition(elem)); Is there a LINQ syntax that would translate to the following? var q = collection.Where((elem, index) => someCondition(elem, index)); ...

How to remove duplicate combinations from a List<string> using LINQ

I'm having a List of String like List<string> MyList = new List<string> { "A-B", "B-A", "C-D", "C-E", "D-C", "D-E", "E-C", "E-D", "F-G", "G-F" }; I need to remove duplicate from the List i.e, if "A-B" and "B-A" exist then i need to keep only "A-B" (First entry) So the result will be like ...

Rendering a hierarchy using LINQ?

Hi everyone, Let say we have a class Category { ID, Name, ParentID } and a List 1, 'Item 1', 0 2, 'Item 2', 0 3, 'Item 3', 0 4, 'Item 1.1', 1 5, 'Item 3.1', 3 6, 'Item 1.1.1', 4 7, 'Item 2.1', 2 Can we using LINQ to render a tree like: Item 1 Item 1.1 Item 1.1.1 Item 2 Item 2.1 Item 3 Item 3.1 Any helps is appreci...

Simplest Way To Do Dynamic View Models in ASP.NET MVC 3

Caveat: This might be an inappropriate use of C#'s dynamic keyword and I probably should be using a strongly-typed view model, but... I'm trying to avoid creating a strongly-typed view model by passing a C# 4 dynamic type to my view. I have this in my controller: public ActionResult Index() { var query = fro...

Using Linq Aggregate to return array of values

I have something like this: long[] f = new long[4]{1,10,100,1000}; I want to divide 1000 by 100, 100 by 10 and 10 by 1 Is there a way to return results in an array with the results eg/ 10,10,10 UPDATE: This seems to confuse a few so here is another example long[] f = new long[3]{1,2,6}; I want to divide 6 by 2 and 2 by 1 with the ...

Group by element in Linq

Lets assume we have the following array var arr = new string[] {"foo","bar","jar","\r","a","b,"c","\r","x","y","z","\r"); Also ignore the fact that this is strings, so no string hack solutions please. I want to group these elements by each "\r" in the sequence. That is, I want one array/enumerable with "foo","bar","jar" and another w...

how can i conver the below SQLQuery into LINO......

SELECT t_PersonalInformation.personalInformation_Name, t_PersonalInformation.personalInformation_PresentAddress, t_PersonalInformation.personalInformation_PermanentAddress, t_PersonalInformation.personalInformation_Phone, t_PersonalInformation.personalInformation_Email, t_Applicant.appl...

What will be the LINQ query for the below SQL Query

SELECT t_PersonalInformation.personalInformation_Name, t_PersonalInformation.personalInformation_PresentAddress, t_Applicant.applicant_TotalExperience, t_Experience.experience_CompanyName, t_Experience.experience_Responsibilities, t_Training.training_TitleDetails FROM t_Applic...

.NET LINQ: Check array index and length EXCEPTION.

Hi All I have the following method: /// <summary> /// Gets the specified side of trades. /// </summary> /// <param name="tradesDictionary">The trades dictionary.</param> /// <param name="side">The side.</param> public IEnumerable<TradeRecord> GetTrades(Dictionary<Guid, TradeRecord> tradesDictionary, Side side) { return (from tradeR...

LINQ OrderBy versus ThenBy

Can anyone explain what the difference is between: tmp = invoices.InvoiceCollection .OrderBy(sort1 => sort1.InvoiceOwner.LastName) .OrderBy(sort2 => sort2.InvoiceOwner.FirstName) .OrderBy(sort3 => sort3.InvoiceID); and tmp = invoices.InvoiceCollection .OrderBy(sort1 => sort1.Inv...

Calling a method in a linq foreach - how much overhead is there?

I'm thinking of replacing a lot of inline foreaches with Linq and in so doing will make new methods, e.g. Current: foreach(Item in List) { Statement1 Statement2 Statement3 } Idea: List.Foreach(Item => Method(Item)) Obviously Method() contains Statement1..3 Is this good practise or is calling a method thousands of times...

Is there a LINQ equivalent method?

Folks, I know LINQ has a SequenceEquals method. This method makes sure each item value in each collection matches, in the same order. What I'm looking for is a more "Equivalent" type of functionality. Just that both sequences contain the same items, not necessarily in the same order. For example, nUnit has CollectionAssert.AreEqual(...

Implementing conditional 'if' statements within a LINQ queries 'where' statement

I'm trying to figure out a way of querying an object in my datamodel and include only those parameters that are not null. Like below: public List<Widget> GetWidgets(string cond1, string cond2, string cond3) { MyDataContext db = new MyDataContext(); List<Widget> widgets = (from w in db.Widgets where ...

Gridview filter and sorting using LINQ

I'm upgrading a project to .net 4. My GridViews are using DataSets and implement filtering, sorting and paging using an ObjectDataSource. What is the best practice to connect a GridView to a Linq query and implement sorting, filtering and paging? Do i still use a DataSet and ObjectDataSource or is there a way to use another type of Da...

Expression Trees as the basis for user defined query engine (using EAV)?

I'm supporting a multi-tenant system that allows users to define custom forms. The data model is EAV based because issuing dynamic DDL to change table schema doesn't work when supporting multiple tenants in a single DB. An upcoming requirement is to build a flexible query designer that allows users to setup simple predicates against th...

Get Range of integers with linq

I'm looking for a way to compute the range of a give set of number for example. if I had H555,H567,H589,H590,H591,H592,H593,H594,H595,H596,H597 I would like output of H555,H567,H589-H597. I have looked through relevant questions and can not find anything like what I'm looking for. Thanks ...

Quick query to retrieve binary image on Image Load?

Is there such a thing?! So for eample, on my image load I have the following hooked up to a table where "Image" is a binary image set of data. protected void Image1_Load1(object sender, EventArgs e) { myent logo = new myent(); var query = (from p in logo.tblLogoes where p.Id == id && p.Id2 == ...