Click here to Skip to main content

Submit your article

LINQ

LINQ

Great Reads

An extensible ExifReader class with customizable tag handlers

by Nish Nishant

An ExifReader class in C# that supports custom formatting and extraction. StyleCop compliant code, with demos for WPF and Windows Forms.

Introducing Calcium for Xamarin.Forms

by Daniel Vaughan

Create best-in-breed cross-platform MVVM apps using Calcium for Xamarin.Forms.

Manageable Services

by Roman Kiss

This article describes a design, implementation and tooling of model driven WorkflowServices logically centralized in the Repository and physically decentralized for their runtime projecting.

Notification of Silverlight Applications about Database State Changes

by Max Paulousky

This article presents the techniques and caveats of building Silverlight applications that can be notified about database state changes via polling duplex. WSHttp binding and CLR triggers are used to implement the solution as well.

Latest Articles

Save Your Settings in a File in JSON and using LINQ for Read and Save

by Dario Picca

Save Key and Value in JSONformat using C# and LINQ

The Workings of Dynamic Lambda in LINQ

by Tragdor

A quick lesson in LINQ and dynamic Lambda statements

Iterator Benchmarks that Shocked with Unexpected Results

by Dev Leader

This article is follow up content to previous articles I've written about iterators and collections, but the benchmark results were NOT what I expected!

A Beginners Guide for LINQ with C#

by Kenji Elzerman

Let's take a look at the very fundamentals of LINQ and how to use it.

All Articles

LINQ

21 Jan 2013 by Srinivasu Pemma

This tip provides an easy way of dealing with different types of data sources for LINQ Group By taken from my blog http://www.srinetinfo.com/2012/12/linq-group-by.html

How to Automatically Close Un-closed HTML Tags using C# for ASP.NET Web Applications

7 Oct 2014 by Milad Ashrafi

We need this script for database based ASP.NET websites for using HTML content in post pages.

How to Convert LINQ Query to DataTable

3 Sep 2014 by debashishPaul

How to convert LINQ query to DataTable

SortedSet Linq Extension Method

26 Oct 2010 by Matt T Heffron

Since SortedSet has a constructor that takes an IEnumerable parameter, the ToSortedSet extension method can be greatly simplified:public static SortedSet ToSortedSet(this IEnumerable t){ return new SortedSet(t);}

Convert LINQ to Entity Result to a DataTable

22 Mar 2011 by Mohammad Al Hoss

entity-framework

See the SQL Generated by LINQ

8 Apr 2011 by Henry Minute

Or, there's always Scott Guthrie's LINQ To SQL Debug Visualizer[^].[Edit]While I'm posting links there is a nice utility that can output the generated SQL to the Debug Window in VS written by Kris Vandermotten.You can get it here[^].To use it: MyDataContext db = new...

Multiple Indexers in C#

25 Jan 2012 by Sion Cohen

An elegant programmatic solution for having multiple indexers in C#

Uploading multiple files and creating a Zip File in ASP.NET with C#

18 Jul 2013 by Mannava Siva Aditya

Uploading multiple files and creating a Zip file in ASP.NET with C#.

Entity Model to Excel using LINQ in C#

31 Oct 2013 by Debopam Pal

How to bring data from Entity model to Excel file using LINQ.

SQL-Server-2008

Dynamic paging in Entity Framework

14 Apr 2014 by Maninder Singh Puhi

Appropriate query to fetch required no of results from DB instead of getting all at on time for binding controls like Gridview, listview etc

entity-framework

Finding Non-disposed Contexts in Entity Framework 6.x Applications

28 Sep 2014 by Vahid_N

It's easy to forget not disposing object contexts, which leads to memory leaks and also leaves too many related connection objects not disposed as well.

Linq Joins with SelectMany

19 Jan 2011 by Pranay Rana

Linq Joins with SelectMany

When to use PLINQ vs LINQ

27 Apr 2012 by Tony Dubey

This code demonstrate pros and cons of PLINQ as compared to LINQ

Dynamically creating a predicate delegate

29 May 2014 by Randy Kroeger

Created a POC that dynamically builds a predicate using Expression and Reflection.

15.2 What's New for XAF

29 Nov 2015 by Michael Bogaerts

What brings the 15.2 release for XAF (win) developers

entity-framework

LINQ To Entity Outer Join

21 Apr 2010 by Mr Orange

Introduction...

entity-framework

Using Extension Methods To Avoid XML Problems

17 May 2010 by Rama Krishna Vavilala

I will just make it a little more compact by omitting the Contains method:public static string GetValue(this XElement root, string name, string defaultValue) { return (string)root.Elements(name).FirstOrDefault() ?? defaultValue; }The explicit operators for XElement...

Duplicate Notifier for a List using ObservableCollection

7 Mar 2012 by Sunil_Sebastian

Duplicate Notifier for a List using ObservableCollection.

Real-time statistics with Rx (Statistical Demo App 1 of 2)

10 Jan 2015 by John L. Vidal

Know how an event in your app is performing by using Reactive Extensions

Creating Presentation Objects with PresentationMapper

29 Apr 2015 by HUONG Minh-Luong

How to use PresentationMapper to generate presentation objects

Linq, Lambda and Expressions

12 Dec 2015 by aboubkr90

A way around "The LINQ expression node type 'Invoke' is not supported in LINQ to Entities"

A better way to count(*)

8 Jun 2010 by basementman

Or, assuming your table has an index, you could do this "old-school" as:select MAX(rows) from sysindexes where id = Object_ID('{tablename}')

How to dynamically retrieve results from a LINQ Query

3 Dec 2010 by -james

Iterate through the results and extract using system.reflection

How to log your LINQ query

20 Oct 2011 by jim lahey

I prefer to use ToTraceString() on the ObjectQuery:http://msdn.microsoft.com/en-us/library/system.data.objects.objectquery.totracestring.aspx[^]It's less intrusive as I don't have to instantiate and dispose the StreamWriter and I have more control over where and how I log the resultant...

Simple jQuery Carousel Matrix 2D AJAX

28 Feb 2013 by Dav Zen

Simple and easy to use jQuery matrix 2D.

Paging DataGridView in C# using LINQ

5 May 2013 by mohammad amiri

Paging DataGridView using LINQ in C#.

Automated Serializer for WinRT Platform

19 Aug 2014 by Alberto Nuti

How to serialize an object without having to manually instruct the DataContractSerializer class.

Run SQL queries on datatables with SqlToDataset

14 Feb 2015 by DerStauner

With this library it is possible to query datatables with SQL commands.

Tip – Walk Before You Can Run

26 Aug 2018 by Toby Steed

Walk before you can run

Fixes to LINQ to SQL Explicit Client Evaluation which Causes Poor Performance

25 Dec 2021 by scott_liu

Entity Framework Core client evaluation was disabled by default since version 3.0 because of performance.

Generating sequential indices using LINQ

17 Jan 2011 by Michael Agroskin

Many LINQ functions have a hidden parameter useful to generate or analyze sequential indices

String concatenation using LINQ to create a CSV/PSV string

29 Jun 2011 by Erich Ledesma

I rather like IEnumerable than IList, parameters should be as general as posible. I think it's really getting very fun up here. Here's my choice, just for strings.public static string Join(this IEnumerable parts, string separator){ if (! parts.Any()) return...

Converting Array or List of data to String => made easy! (C#, MVC3, LINQ)

18 Jan 2012 by Namlak

string blah = string.Join(",", cities.Select(c=> c.Name));

Filtering records from List similar to Sql IN Operator using LINQ

27 Feb 2012 by Rishikesh_Singh

Filtering records from List similar to Sql IN Operator using LINQ

Creating Func delegates using TextToCalcExpression

16 Mar 2012 by Carlos Conceição

This article how you can use TextToCalcExpression to generate Linq Expressions in runtime

Select Recursive Extension method

7 Sep 2010 by John Adams

Magnus, I really like the idea! I believe your original idea (posted @ http://www.codeproject.com/KB/linq/LinqToTree.aspx) is even better for the general case - probably better than the solution in the article - it does feel more generic while still being very easy to use.I'm sure you may...

String concatenation using LINQ to create a CSV/PSV string

26 Jun 2011 by JP_Rocks

A tip to concatenate a set of strings using comma/pipe

See the SQL Generated by LINQ

17 Jul 2011 by Philippe Mori

LINQPad is an interesting tool to try queries.LINQPad[^]Perfect tool to try out some alternatives for complex queries. As we can see generated queries and elapsed time, it help a lot to help having fast queries for complex requests.

See the SQL Generated by LINQ

18 Jul 2011 by AspDotNetDev

If you are the type that likes to debug production code, you can use SQL Profiler to find queries generated by your LINQ statements. This is a technique I recently used because it was so simple and did not require me to recompile anything.Note that StefanHam already posted this alternate...

Introduction to Linq To WMI with Code Generation GUI

17 Aug 2011 by John Wigger

Data Tables to Formatted XML (for loops vs. LINQ to XML)

2 Oct 2011 by Vishnu Kesaraju

Using LINQ to XML to convert datatables to formatted XML.

Get basic intuition about how LINQ works

8 Nov 2011 by Delashmate

Deep Look in the basics of LINQ

Using SQL Bulk Copy with your LINQ-to-Entities datacontext - Part 1

27 Aug 2013 by Måns Tånneryd

This tip shows how to significantly speed up inserts of large amounts of data using the entity framework.

Optimizing linq queries that retrieve a single element

14 May 2012 by taha bahraminezhad Jooneghani

Problem around .first() method in EF and a good solution

web_development

The Elegant Art of Programming

18 May 2012 by PIEBALDconsult

This is an alternative for "The Elegant Art of Programming"

Querying DataSet With LINQ in ASP.NET

31 Jul 2012 by HemendraSingh88

Hi, here we will see how to query a DataSet with LINQ(Language Integrated Query).

CheckBoxList ASP.NET MVC3

8 Sep 2012 by suhas.shiv

Custom CheckBoxList in ASP.NET MVC3

Excel To DataBase Table

3 Nov 2012 by Sarvesh Kushwaha

Export Excel to SQL database table (Sample Code)

Like Magic, No Strings Attached

28 Mar 2013 by dgDavidGreene

Helper utility replaces magic string property names.

Web API Data Structure Controller

10 Mar 2013 by xibao

Generate class definition for Web API Service Models.

Make Comma Separated List the Easy Way

28 May 2013 by David_Wimbley

How to make a comma separated string using Linq

Using SQL bulk copy with your LINQ-to-Entities datacontext - Part 2

26 Aug 2013 by Måns Tånneryd

This tip shows how to speed up inserts using POCO objects and the entity framework version 5.

To Generate XML File from Datatable using LINQ

23 Feb 2014 by puja11191

This tip shows how can we generate and save XML files

EF Remove If Exists

12 Apr 2014 by Robert Lindblom

Removing entity if it exists

Verify Resources Used by DisplayAttribute

17 Feb 2015 by Christ Akkermans

Code for verifying the resources used by DisplayAttribute in order to catch any missing resource strings

Generic LINQ Usage To Return Single Value From DataRow

15 Jul 2010 by Paul Brower

This tip will allow you to return the value from column X, where column Y matches your filter

Get Selected CheckBoxes from container

24 Jan 2011 by karenpayne

Returns all checked Checkbox controls in a Windows Form container

Silverlight, PLINQ, and my take on a Semaphore variant.

26 Jun 2011 by Alex Perepletov

String concatenation using LINQ to create a CSV/PSV string

29 Jun 2011 by Mohammad A Rahman

The idea was good, but I think we could probably do something like below:public static string UsingStringJoin(IEnumerable sList, string separator){ return sList.Any() ? string.Join(separator, sList.ToArray()) : string.Empty;}public static string...

String concatenation using LINQ to create a CSV/PSV string

30 Jun 2011 by George Swan

You can use the Aggregate method with a StringBuilder. I've modified Eric's alternative in order to save a bit of code. Only one return statement is needed as an empty StringBuilder returns an empty string.public static string Join(this IEnumerable parts, string separator) { ...

Generic DropDown Control Using LINQ to SQL and Entities using Reflection

21 Aug 2011 by murtaza dhari

A generic dropdown control using LINQ to SQL and Entities using Reflection

Solution to annoying error 0029 - Cannot convert type 'T' to 'System.Data.Linq.Link'

29 Aug 2011 by Itai Basel

Finally found a solution to the annoying LINQ to SQL dbml error: CS0029 : Cannot implicitly convert type 'int' to 'System.Data.Linq.Link'.

DataLoadOptions and How to use in Compiled Linq query

13 Nov 2011 by Pranay Rana

DataLoadOptions and How to use in Compiled Linq query

Converting Array or List of data to String => made easy! (C#, MVC3, LINQ)

4 Feb 2012 by jarvisa

string.Join(",...

Using SQL bulk copy with your LINQ-to-SQL datacontext

23 Feb 2012 by RupertC

If the order of your columns is different in the LINQ to SQL class from that in the database, then you also need to add a column mapping to the bulk copier. Otherwise you get mysterious errors in some of the loaded columns!In my simple fix, I assume that the names match even if the order may...

Cumulating values with LINQ

27 Jul 2012 by Wendelius

This is an alternative for "Cumulating values with LINQ"

WebMonster

4 Oct 2012 by ravichaitanya.m

The code shown here allows a user to get all public tweets of her /his liking without logging into Twitter and search for tweets with keywords. It also allows the user to search for his/her friends who are tagged in his/her albums.

Selecting Distinct Records Using LINQ

15 Oct 2012 by Eric Shandil

How to get dictinct records from a datatable in .NET.

Get LINQ GetCommand Parameters

5 Dec 2012 by moosa pourghafari

Get LINQ GetCommand parameters.

New methods of coding (at least for some)

3 Sep 2013 by karenpayne

Using newer conventions of coding in VS2010 and higher

Subset - Sum Problem with Numeric Collections

17 Apr 2014 by Matt T Heffron

This is an alternative for "Subset - Sum Problem with Integer Arrays "

Re-usability of View in MVC

18 Apr 2015 by Nithila Shanmugananthan

Re-usability of view in MVC

AutoCompleteExtender working with EntityFramework! (Reload 2015)

12 Nov 2015 by Eduardo Yost

Creating a Web User Control containing an AutoCompleteExtender for data through WCF (JSON) allowing to store the entity selected through EntityFramework. Entity object serialization from the server to the client and the client to the server.

See the SQL Generated by LINQ

26 Feb 2010 by MarkLTX

When using LINQ to SQL, it can be very useful to see the SQL commands that are generated by your LINQ expressions. Sometimes the results are surprising and you might be able to improve performance by tweaking the LINQ.All you have to do is set the Log property of the DataContext object. ...

EBCDIC to ASCII Converter

18 Feb 2018 by Max Vagner

Converting mainframe EBCDIC to ASCII format

Flatten a Hierarchical Collection of Objects with LINQ

18 Jul 2012 by Yves Vaillancourt

Adding an extension method to LINQ to flatten any hierarchical collection

Big n Bulky "How To" Document for ASP.NET MVC, Entity Framework, LINQ, HTML 5 and JQuery

28 Sep 2014 by Bhushan Mulmule

This is terribly unorganized document with mix of MVC, Entity Framework, LINQ, HTML 5 and JQuery how tos...

Flatmapper

9 Feb 2016 by João Matos Silva

FlatMapper is a library to import and export data from and to plain text files

Using SQL bulk copy with your LINQ-to-SQL datacontext

25 Jan 2012 by Måns Tånneryd

How to use bulk insert with your LINQ-to-SQL datacontext

SimpleThreading Makes Threading Easy!

4 Aug 2017 by Sharp Ninja

Threading can be a daunting topic. This library takes much of the worry (and mistakes) out of multi-threaded application programming.

LINQ Basics

11 Jan 2021 by Uladzislau Baryshchyk

Basics of the embedded LINQ language

Expressmapper - The New .NET Mapper!

13 Jul 2015 by Yuriy Anisimov

Expressmapper - lightweight, lighting fast and easy to use .NET mapper

Editing Enumerator within foreach loop (well, not really)

26 Jan 2011 by dan!sh

A simple way to edit a list or collection which is iterated in a foreach loop

Resampling and merging time series data using LINQ

29 Apr 2014 by Ashley Davis

The technique presented here is a simple method of resampling and aggregating time series.

Query Hierarchical DataTable

5 Oct 2015 by Wendelius

This tip shows one way to query hierarchical data from a DataTable by using an AsTree() method.

Building OrderBy Lambda Expression from Property Name in C#

10 Sep 2014 by DiponRoy

Let's make a lambda expression from a property name of a particular entity, and use it for OrderBy shorting

22 Apr 2014 by Member 3531622

Get rid of trivial mapping between objects like mapping between obj1.City and obj2.Town or between properties with the same name

Using `Environment.SpecialFolder` to Maximize Portability

26 Apr 2016 by _Noctis_

How to avoid some hardcoded paths with the uses of Environment.UserName

Read XML Files and Insert into Database Table

25 Jan 2016 by Gunaprasad Shetty

The tip provides the code snippet for inserting a huge XML file with details such as node level, node value, node desc and node child, etc.The snippet provides the solution for recursive reading of node and provides the value of XML nodes along with its value.

SQL-Server-2012

Using LINQ to read delimited text files

28 Mar 2010 by The Manoj Kumar

Did you ever face a situation where you want to read a delimited file (CSV or any similar format) and want to filter the records on the basis of some conditions (by checking some values against columns).For example, let's assume that Data.txt file contains the following...

1 Oct 2015 by VijayRana

Some useful MVC Attributes (Bind Attribute, HandleError Attribute, HiddenInput Attribute, Remote Attribute)

The Elegant Art of Programming

21 May 2012 by Juan Pablo G.C.

This is an alternative for "The Elegant Art of Programming"

Most Useful VS2013 Tricks and Shortcuts!!

28 Dec 2014 by Pritam Deshmukh

This tip elaborates few useful tricks and shortcuts of VS 2013 mainly for professional edition (You can find them with Ultimate version too).

Ensure Your Code First DB is Always Initialized

27 Jun 2012 by Brady Kelly

A quick and easy way to ensure that your Code First DB Initializer is always run when your app starts, not just on the first data access operation

ComboBox with Suggest Ability based on Substring-Search

5 Aug 2013 by Physlcu$

A custom ComboBox that supports live filtering of items by Substring-Search or any other Lamda-Expression

Dynamic Sorting in LINQ

8 Oct 2013 by Thomas Corey

Dynamically sort query results using LINQ expressions and reflection.

Understand Lambda Expressions in 3 Minutes

5 Mar 2013 by Dan Avidar

Lambda expressions short tutorial

Generic repository pattern using EF with Dependency injection (Ninject)

14 May 2013 by vijay__p

How to perform CRUD operations using generic repository with EF pattern with and dependency injection.

Build Where Clause Dynamically in Linq

6 May 2014 by Fitim Skenderi

Build where clause dynamically in Linq

DataReader into IEnumerable with C#

4 Nov 2013 by Jaume González

How to convert any datareader into generic list.