linq

Open source LINQ search engine for website

I want to add a search engine to my website. I want it to handler boolean searches and give me a list of results in order or best match. I need it to be able to work with LINQ, because I want to add additional where clauses to the final query that gets run. I am looking for the best open source .NET search engine that works with LINQ. I...

Navigating by foreign keys in ADO.NET Entity Framework/MySQL

I am using ASP.NET MVC2 on top of a MySQL database in VS2008. I am using the MySQL ADO.NET connector 6.2.3 to provide the connection for the ADO.NET Entity Data Model. This is mostly working ok, however navigating via foreign keys is causing me a real headache! Here is a simplified example.. Car (Table) CarID PK Colour Doors Manufactu...

How can I use plinq to fill an array with strings returned from my "FormatStatus" Method?

This is my first time playing around with linq and I can't quite figure out what I need to search on google to find out what I am doing wrong, so here I am. Here is what I have so far: var formattedStatuses = (from status in _statusCollection select FormatStatus(status)).AsParallel(); ...

LinqToSql Select to a class then do more queries

I have a LINQ query running with multiple joins and I want to pass it around as an IQueryable<T> and apply additional filters in other methods. The problem is that I can't work out how to pass around a var data type and keep it strongly typed, and if I try to put it in my own class (EG: .Select((a,b) => new MyClass(a,b))) I get errors w...

ControlCollection extension method optimization

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...

Using Linq to group a list of objects into a new grouped list of list of objects

Hi, I don't know if this is possible in Linq but here goes... I have an object: public class User { public int UserID { get; set; } public string UserName { get; set; } public int GroupID { get; set; } } I return a list that may look like the following: List<User> userList = new List<User>(); userList.Add( new User { UserID =...

Do I need to include all fields in my entity framework model

Quick question for everyone: Do I need to include all the database table fields on my EF model? For example; I've created a sub-model that only deals with tblPayment and associated tables. Now, I need to write a LINQ query to get some information about items. I would typically get this by joining tblPayment to tblInvoice to tblInvoic...

Linq TakeWhile depending on sum (or aggregate) of elements

I have a list of elements and want to takeWhile the sum (or any aggregation of the elements) satisfy a certain condition. The following code does the job, but i am pretty sure this is not an unusual problem for which a proper pattern should exist. var list = new List<int> { 1, 2, 3, 4, 5, 6, 7 }; int tmp = 0; var listWithSum = from x i...

remove schema from linq datacontexts

When I add stored procedures to a linq datacontext, by default visual studio prefixes the stored procedure with the sql schema that it is in. Is there any way to stop this? In our environment, the stored procedures may be moved to other schemas over time, and we will default the schema based on the sql user used to connect. Do I have ...

C#: How to remove items from the collection of a IDictionary<E, ICollection<T>> with LINQ?

Here is what I am trying to do: private readonly IDictionary<float, ICollection<IGameObjectController>> layers; foreach (ICollection<IGameObjectController> layerSet in layers.Values) { foreach (IGameObjectController controller in layerSet) { if (controller.Model.DefinedInV...

What's FirstOrDefault for DateTime in Linq?

If I have a query that returns a DateTime, what's the value of FirstOrDefault? Is there a generic way to get the default value of a C# scalar? Example: var list = (from item in db.Items where item.ID==1234 select item.StartDate).FirstOrDefault(); Edit: Assume that the column StartDate can't be null. ...

Linq - Orderby not ordering

Hello everyone, I have a linq query that for whatever reason is not coming back ordered as i would expect it to. Can anyone point me in the right direction as to why and what i am doing wrong? Code is as follows: List<TBLDESIGNER> designer = null; using (SOAE strikeOffContext = new SOAE()) { //Invoke the query designer = AdminD...

Generic List .First not working LINQ

var stuff = ctx.spReport(); var StuffAssembled = new List<ReportCLS>(); var val = new List<ReportCLS>(); foreach (var item in stuff) { StuffAssembled.Add(new ReportCLS(item)); } val.Add(StuffAssembled.First()); Keeps throwing System.Collections.Generic.List' does n...

Entity Framework query

Hi all, I have a piece of code that I don't know how to improve it. I have two entities: EntityP and EntityC. EntityP is the parent of EntityC. It is 1 to many relationship. EntityP has a property depending on a property of all its attached EntityC. I need to load a list of EntityP with the property set correctly. So I wrote a piece ...

How to pass output of a linq query to another form in C#

I have a Linq query and I want to pass the ouput (userid) to another form for further processing. var userid = from auser in allusers.Users where auser.Username == nameString select new { id = auser.UserId }; so only 'UserId' is stored in variable 'userid' and I want to use this value in another form. Is there any way we can ...

How can I evaluate a deferred Linq statement when debugging?

I'm debugging in VS2010, and I want to inspect a string value but all I can get the debugger to show me (through watches, hovering, locals, etc.) is: "System.Linq.Enumerable+<TakeIterator>d__3a`1[System.Char]" I don't care if there are side effects from premature evaluation or whatever, I just want to see what the expression would ev...

Using LINQ to XML, how can I join two sets of data based on ordinal position?

Using LINQ to XML, how can I join two sets of data based on ordinal position? <document> <set1> <value>A</value> <value>B</value> <value>C</value> </set1> <set2> <value>1</value> <value>2</value> <value>3</value> </set2> </document> Based on the above fragment, I would li...

Is saving to database just to get an ID a bad hack?

I hope the title is not too confusing. I am trying to make folders with linq-to-sql objects' IDs. Actually I have to create folders before I should save them. I will use them to keep user uploaded files. As you can see I have to create the folder with the FileID before I can save it there. So I just save a record which will be edited or ...

Using LINQ to SQL in ASP.NET MVC2 project

Well I am new to this ORM stuff. We have to create a large project. I read about LINQ to SQL. will it be appropriate to use it in the project of high risk. i found no problem with it personally but the thing is that there will be no going back once started.So i need some feedback from the ORM gurus here at the MSDN. Will entity framewor...

linq - how to sort a list

Hello everyone, I have a linq query that populates a list of designers. since i am using the filters below my sorting is not functioning properly. My question is with the given code below how can i best sort this List after the fact or sort while querying? I have tried to sort the list after the fact using the following script but i...