linq

C#: Adding Columns To Bound DatagridView With Code

// Getting data from this Admin class: public static IQueryable<Student> GetStudents() { DojoDBDataContext conn = new DojoDBDataContext(); var query = from s in conn.Students join b in conn.Belts on s.BeltID equals b.ID orderby s.LastName ascending select s; return query; } // And on my fo...

Proper way to format date from database using javascript/jquery

Hi all, I am calling my database which contains a datetime datatype. The date looks like this: 2005-05-23 16:06:00.000 I would like to display this in a table when a user selects a certain item from a list. I call my controller action and return Json of all the times and put them in a table. The problem is the date is completely wrong...

How to sort linq result by most similarity/equality

I want to do a search for Music instruments which has its informations Name, Category and Origin as I asked in my post. But now I want to sort/group the result by similarity/equality to the keyword such as. If I have the list { Drum, Grand Piano, Guitar, Guitarrón, Harp, Piano} << sorted by name and if I queried "p" the result should ...

Is it possible to compile a query for linq-to-objects

I have a linq to objects query in a recursive loop and afraid when the objects approach more then 1000 and a have more then 100 users on the site -- my website will break. so is it possible to compile a linq to objects query. The linq query does nothing more then find the direct children of a node. ...

How to access a method on a generic datacontext which is only created at runtime

I'm creating my generic DataContext using only the connectionString in the ctor. I have no issues in retrieving the table using DataContext.GetTable(). However, I need to also be able to retrieve entities of inline table functions. The dbml designer generates public IQueryable<testFunctionResult> testFunction() { return thi...

Getting the first result from a LINQ query - why does ElementAt<T>(0) fails when First<T>() succeeds?

I have a method AddStudent() which looks for a student with the same name and returns an existing student from the database if there is a student with the same name, otherwise it creates a new student and adds it to the database. I'm curious why se = students.First<StudentEntity>(); succeeds when se = students.ElementAt<StudentEntity>(0...

Does Castle ActiveRecord's ActiveRecordMediator<> support LINQ?

Does Castle ActiveRecord's ActiveRecordMediator<> class support LINQ queries? I couldn't find any method that returns an IQueryable<>. My domain objects can't inherit from ActiveRecordLinqBase<> due to their design. ...

What are some linq "best practices"

Looking to use linq throughout my next project to ease some of the hard labor. Before, I dive into the linq world I would like some advice on best prctices on using linq. I am still undecided on EF and linq to sql ...

Select some records ...

I have an IList<MyList>. I'd like with LINQ keep the same list (same number of record) but I'd like reduce or/and rename some record. At the end I'd like to have IList<MyNewList>. Update (Marc Gravell request) We have tools to generate interface/object from Oracle stored procedure. My problem is, for some stored procedure, a lot of fiel...

Linq Order By a subtable

Hello, My question is how to sort a Linq query by a sub table: Table Apps: - app_id - name Table AppStatus: - app_status_id - app_id - severity - status_date I would like to have a query with all the apps, sorted by the last status severity: app_id name 1 first 2 second 3 third app_status_id app_id severity sta...

LINQ to SQL: Reusable expression for property?

Pardon me for being unable to phrase the title more exact. Basically, I have three LINQ objects linked to tables. One is Product, the other is Company and the last is a mapping table Mapping to store what Company sells which products and by which ID this Company refers to this Product. I am now retrieving a list of products as follows:...

LINQ vs Lambda vs Anonymous Methods vs Delegates

Can anyone explain what are the LINQ, Lambda, Anonymous Methods, Delegates meant? How these 3 are different for each other? Was one replaceable for another? I didn't get any concrete answer when i did Googling ...

Update a record in L2S and L2E

I was told in L2S, the code for update and insert are the same, db.InsertOnSubmit(row); db.SubmitChanges(); and L2S will check to see if it is a insert or update and act approprately in the background. Is that true? How about L2E? I tested, looks like in L2E it is not like that. Maybe I did something wrong. ...

How do make unwanted namespaces to not appear by default on top of new classes

In Visual Studio 2008 C#, if I create a new class the following namespaces appear by default and I remove them manually every time. Is there a setting/folder template where I can go and remove these unwanted namespaces from appearing on each and every new class that's created on the project? using System.Collections.Generic; using Syste...

How to access data from multiple tables

Hi All, How to write linq query to access data from multiple table.How do you write Linq query for the following sql query:- "select * from user,employee where user.Name='smith' and employee.company='xyz'" ...

Linq issue retrieving single value from SQL Server

Hey Guys, having an issue with Linq-to-SQL, I am basically doing the following but it is saying it is "UserProfile does not contain definition for Username" in the current context where I wrote "u.Username" but it does exist I have added UserProfile table to MyDbml.dbml and if I connect to another table it works fine. TiamoDataContext c...

Linq to Datarow, Select multiple columns as distinct?

basically i'm trying to reproduce the following mssql query as LINQ SELECT DISTINCT [TABLENAME], [COLUMNNAME] FROM [DATATABLE] the closest i've got is Dim query = (From row As DataRow In ds.Tables("DATATABLE").Rows _ Select row("COLUMNNAME") ,row("TABLENAME").Distinct when i do the above i get the error Range ...

the best way to convert delimited to fixed width

What is the BEST way to convert this : FirstName,LastName,Title,BirthDate,HireDate,City,Region Nancy,Davolio,Sales Representative,1948-12-08,1992-05-01,Seattle,WA Andrew,Fuller,Vice President Sales,1952-02-19,1992-08-14,Tacoma,WA Janet,Leverling,Sales Representative,1963-08-30,1992-04-01,Kirkland,WA Margaret,Peacock,Sales Representativ...

XML to Type - Quick way?

Team; How are you doing? Im breaking my head trying to do this that seems simple but I can't figure it out... Suppose I have this XML as a string: <calles> <calle> <nombre>CALLAO AV.</nombre> <altura>1500</altura> <longitud>-58.3918617027</longitud> <latitud>-34.5916734896</latitud> <barrio>Recoleta</barrio> </calle>...

Exploding a range of dates with LINQ

If I have a pair of dates, and I want to generate a list of all the dates between them (inclusive), I can do something like: System.DateTime s = new System.DateTime(2010, 06, 05); System.DateTime e = new System.DateTime(2010, 06, 09); var list = Enumerable.Range(0, (e - s).Days) .Select(value => s.AddDays(value)); What I'm stuck o...