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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

An extensible ExifReader class with customizable tag handlers

29 Mar 2010 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

15 Sep 2014 by Daniel Vaughan

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

Manageable Services

30 Apr 2009 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

27 Nov 2009 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.

SQL-Server-2005

Hierarchy of Categories and Classifying Wikipedia Articles using XML Dump

9 Apr 2021 by Ilia Reznik, Vladimir Shatalov

How to classify articles on Wikipedia using XML dump

Introduction to Model Driven Development with Sculpture – Part 1

3 Sep 2008 by Ahmed Negm

This article introduces how to create and manage .NET enterprise applications using your favorite technology (Data Access Application Block, LINQ, NHibernate, ASMX, and WCF) with the Model Driven Development approach by Sculpture.

SQL-Server-2005

C# Linq Expressions in Easy Samples

30 Oct 2022 by Nick Polyak

Explains concepts of Expression programming by simple examples

10 Oct 2012 by Andrew Rissing

An intuitive-fluent API for generating Linq Expressions.

Dynamic Table Mapping for LINQ-to-SQL

21 May 2012 by Zimin Max Yang

Dynamic table mapping for LINQ-to-SQL, suitable for data horizontal partitioning (Shard).

LINQ To Google Image and Google Groups

8 May 2007 by Ming.Chen

A LINQ Implementation for Google Images/Groups Search

WCF by Example - Chapter VII - Decoupling of WCF Services from the ViewModel

11 Oct 2011 by Enrique Albert

Baseline WCF Distribution Layer - Decoupling of WCF Services and ViewModels.

How to Implement Generic Queries by Combining EntityFramework Core and GraphQL.NET?

8 Jan 2018 by thangchung

This article will show you how to expose the database schema to the APIs, then query from it. No boilerplate code for simple query actions. Go and read it.

SOLID Poker - Part 2 - Compare Poker Hands

7 Apr 2017 by Marco-Hans Van Der Willik

This article continues with the development of the SOLID Poker project, and covers functionality to Compare and Validate Poker Hands.

Nullable datetime column in .NET DataGrid with DateTimePicker

17 Aug 2009 by vic_ch2000

A nullable datetime column in .NET DataGrid with DateTimePicker.

Using LINQ for type Conversion

25 Feb 2010 by dasblinkenlight

Converting between types in .NET

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

WuffProjects.CodeGeneration

28 Feb 2016 by WuffProjects

WuffProject.CodeGeneration is an easy to use, reliable and powerful code generation framework

Mr. Crossworder - Create Crosswords in Seconds!

6 Jan 2019 by Mehedi Shams

Crossword creator - with a touch of Unicode Logic!

7 Sep 2009 by Tamer Oz

PocketPcAgent is an application that can be installed on Windows Mobile devices that are running Windows Mobile 5.0 or higher. The application listens to events such as SMS Received, Call Missed, E-Mail Received, Battery Strength Changed, and much more on the Pocket PC.

WCF End Point Configuration

10 Aug 2012 by Wonde Tadesse

The following procedures will help you to provide the service.1. Prepare a good documentation for the configurable parts of the wcf service. These configuration parts could be the endpoint, identity etc.2. Use SvcConfigEditor.exe[^] which is provided by Microsoft for such purpose.Note:I...

C# LINQ: Ordered Joining and Grouping Lazy Operators

18 May 2017 by Yuriy Magurdumov

Lazy Joining and Grouping IEnumerable extensions for ordered sequences

Silverlight Cairngorm - Port Cairngorm to .NET

6 Oct 2008 by Modesty Zhang

Port Cairngorm 2.2.1 to Silverlight 2 Beta 2. Includes all source code and a sample application.

Windows Workflow (WF) as a WCF Service

17 Jul 2009 by eyedia

Sequential workflow as a WCF service. Create workflow custom activities, invoke child workflow from parent. Configure workflow runtime service using a config file. Basic idea of rules, creating a rule using the rule editor. Applying rules during runtime.

Hacking the Mono C# Compiler.

9 Oct 2010 by Stefan Savev 2

Describes how to dump information from the C# parse tree

virtual-machine

LINQ to Entities, Cross Apply, and Left Outer Join

12 May 2017 by DaveDavidson

In this article, I show LINQ to Entities syntax that will produce queries with CROSS APPLY and LEFT OUTER JOIN clauses.

entity-framework

LINQ Part 3: An Introduction to IQueryable

20 Apr 2018 by Eric Lynch

Part 3 in the LINQ series, this provides an introduction to IQueryable, IQueryProvider, and LINQ expression trees.

noDB

11 Jan 2020 by Mehdi Gholam

Using list of objects, LINQ and SQL like string query instead of a database with fastJSON serializer

Creating a DotNetNuke® Module using LINQ to SQL

24 Jan 2008 by defwebserver

This tutorial will show you how to create a DotNetNuke module using LINQ to SQL.

Lightswitch Job Hunter Application

19 Jan 2012 by stuxstu

Job application tracker for those out of work built using Visual Studio Lightswitch 2011.

Monad like programming with C#

18 Sep 2013 by Muraad Nofal

A haskell monad/(applicative)functor like interface in C# that extends IEnumerable.

Using MVVM to create Tabbed Interfaces with Calcium for Xamarin Forms

17 Sep 2014 by Daniel Vaughan

Create a Xamarin Forms tabbed page or carousel page by binding to a collection of ViewModels; extending beyond the current capabilities of Xamarin Forms.

A Simple Pathfinding Laboratory

7 Sep 2018 by Robert Vandenberg Huang

Experiment, run and compare different pathfinding algorithms and heuristic functions

LINQ to SQL - Detach Entities

12 Jul 2009 by Eric J. Smith, Shannon Davidson

Easily detach entities when using LINQ to SQL

Tool Window Support for LINQ and Lambda, PerfTip and Diagnostics Tool Window in Visual Studio 2015

14 Jun 2016 by Akhil Mittal

This article will cover other debugging improvements of VisualStudio 2015 like the tool window support for LINQ and Lambda expressions, the newperftips, and the new diagnostic tool window.

Angular2 & WebApi (SPA) for Enterprise App - Part 7 - Manage Application Lifecycle

29 May 2017 by tranthanhtu.vn

In this article, We will learn why do we need to manage the stages of our application.

Intertexti - Resurrecting HyperCard

2 Feb 2013 by Marc Clifton

A prototype application for cross-referencing and indexing files, URL's.

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.

A generic equality comparer library which will work across types

14 Nov 2013 by shijo joseph

An extension methods library which could do the equality comparison operations easily

How to Convert LINQ Query to DataTable

3 Sep 2014 by debashishPaul

How to convert LINQ query to DataTable

Optimizing LINQ

29 Sep 2016 by matt warren

How to optimize Linq

An Introduction to ASP.NET Core MVC through an Example (Part 1)

9 Mar 2022 by Coding Notes

An introduction to ASP.NET Core MVC

jLinq 2.2.0 Released!

13 Aug 2009 by webdev_hb

jLinq is a Javascript query language that makes it easy to work with large arrays of information. Today, jLinq 2.2.0 is released which offers new commands, bug fixes and more!

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

Playing Around with LINQ for JavaScript

18 Jun 2015 by Duke Of Haren

Playing around with LINQ for JavaScript

Parsing and Interpreting XSD Using LINQ

6 May 2012 by CodingBruce

How to use a Linq2Xsd generated object to directly manipulate XmlSchema

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...

C# Linq query: Get all items from list which key is in other list

11 Apr 2011 by jim lahey

Using your code, I'd do it like this:var results = records.Where(r => Keys.Contains(r.key));

Multiple Indexers in C#

25 Jan 2012 by Sion Cohen

An elegant programmatic solution for having multiple indexers in C#

Filter Using Linq On datatable with "IN" and "Not In" Clause

8 May 2012 by VJ Reddy

From the question it appears that all rows from datatable, which do not contain JOB in stauscode column are required to be filtered out, as the same datatable is used in the inner query. If that is the case, then I think the following query can be used.var filteredRows = from n in...

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#.

LINQ to Family Tree (Prolog Style)

31 Jul 2013 by Hisham Abdullah Bin Ateya

Querying a family tree in LINQ fashion.

artificial-intelligence

Short But Very Useful regex – lookbehind, lazy, group, and backreference

19 Aug 2013 by morzel

How to match text which is preceded by some other text? How to reference matched text to find closing tag? Read this post if you want to know the answers to these and few other questions.

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.

Difference between two dates in hours

3 Sep 2015 by OriginalGriff

First of, never fetch DateTime.Now more than once: it leads to intermittent problem around midnight which can really mess you up. Fetch it once, and use it for all checks.Then try:DateTime now = DateTime.Now;var receiveDetails = objDB.GetAllReceivedDetails().Where(a =>...

Writing Custom LINQ Extension Methods

17 Jun 2009 by Sacha Barber

How to write custom LINQ extension methods

Why can't this cast be done?

5 Aug 2009 by Pete O'Hanlon

You can't cast it as such because a.Except(b) returns the type System.Linq.Enumerable.ExceptIterator. You have two options here:c.AddRange(a.Except(b)); or c = a.Except(b).ToList(); "WPF has many lovers. It's a veritable porn star!" - Josh...

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

remove item where not saved on insertonsubmitchanges method

31 May 2012 by Shahin Khorshidnia

HelloUse CommittableTransaction in System.Transactions. Maybe you need to add reference.For example:using (System.Transactions.CommittableTransaction transaction = new System.Transactions.CommittableTransaction()){ //... if(new...

how to use inner join in linq query

13 Jun 2012 by Prasad_Kulkarni

Please refer:LINQ TO ENTITIES – JOIN QUERIES[^]Inner, Outer, All Join With LINQ[^]

Error - LINQ/TransactionScope with multiple database connections

26 Jun 2012 by Wonde Tadesse

Have a look these articles.1.Distributed transactions and TransactionScope [how to get it?][^]2.Entity Framework & Transactions[^]3.TransactionScope and DataAdapters[^]4.Handling transactions in .Net using TransactionScope[^]

SQL-Server-2008

Can anyone help me to find out the mistake

30 Apr 2014 by Thomas Daniels

You try to convert a collection of anonymous types to a List with elements of the type ren. Change select new { into select new ren() {List renewedorderlist = (from ordernum in salesContext.SL_OrderIdMapper where ordernum.OrderNumber==placeOrderModel.OrderInfo.OrderID from...

Dynamically creating a predicate delegate

29 May 2014 by Randy Kroeger

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

CRUD Operations Web Application/ XML Data in ASP.NET MVC 4

27 Jan 2015 by luckylaxman

Create, read, update, delete,Log in and Log out, (CRUD) operations are easy to perform in ASP.NET MVC. By using the default T4 scaffolding templates and strongly-typed views you can quickly build a web application that can create, update, and delete records.

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

Difference of two datatables in C# using LINQ

31 May 2016 by Karthik_Mahalingam

try thisDataTable dt1 = new DataTable(); dt1.Columns.Add("ID"); dt1.Columns.Add("Name"); dt1.Rows.Add(101, "ABC"); dt1.Rows.Add(102, "XYZ"); dt1.Rows.Add(103, "MNO"); dt1.Rows.Add(104, "PQR"); DataTable dt2 = new DataTable(); ...

Making an Event Calendar for Trucking/Shipping with C# MVC and jQuery.Fullcalendar

10 Feb 2018 by Changming Wang

A complete event calendar, using trucking/shipping as an example, built with Visual Studio Community 2015, C# MVC and jQuery.Fullcalendar

Descriptive Statistics and Data Normalization with CNTK and C#

1 Jul 2018 by Bahrudin Hrnjica

How to calculate some of the basic statistics operations on data set

Very basic question about linq select method

16 Aug 2019 by F-ES Sitecore

Select is an extension method with the first param (IEnumerable source) marked as "this"; IEnumerable Select(this IEnumerable source, Func selector) The way extension methods word is the object you enact them on is passed to the "this"...

Sql statement to return a list of partial dues

1 Oct 2019 by MadMyche

First things first; it is always helpful to post code that has some formatting to it, which makes it a lot easier for people to read what you are trying to doSELECT distinct RTRIM(Students.StudentNumber) , RTRIM(Students.StudentSurname) , RTRIM(Students.StudentFirstNames)...

QueryMap: Custom Translation of LINQ Expressions

22 Apr 2012 by Overboard Software

QueryMap allows you to pre-translate a LINQ expression into a form that the underlying query provider (such as LINQ to SQL) can understand.

Linq To Object query

6 Sep 2009 by Eslam Afifi

.Skip(m).Take(n)

Leveraging LINQ to XML: Querying an obfuscation map

5 Oct 2009 by Alexander Yegorov

Practical use of LINQ to XML technology.

Leveraging LINQ to XML: Querying an obfuscation map: Part 2

5 Oct 2009 by Alexander Yegorov

A practical use of the LINQ to XML technology.

LINQ: Single vs. First

13 Apr 2010 by Paulo Morgado

LINQ: Single vs. First

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...

Concatenate a string and decimal in a Linq query

15 Jul 2016 by larry118

I am writing an application in VS2010, Framework 4.0, C# and silverlight 4.I have a simple class and Linq Query.The class is:public class pmDues { [Key] public int DuesID { get; set; } [DataMember] public string dues_type { get; set; } ...

Dumping Objects Using Expression Trees

11 Aug 2010 by Paulo Morgado

Dumping Objects using Expression Trees

Need a how to "linq anonymous list to a strong typed list"

7 Feb 2011 by Nish Nishant

Typically this is done with a call to Cast(). I don't know the VB syntax to call it, so check this page out:http://msdn.microsoft.com/en-us/library/bb341406.aspx[^]

XDocument Parse- Element("ServiceResponse").Element("Message").Value returns null

15 Feb 2011 by Fredrik Bornander

You're running into problems because you're trying to read elements in a namespace without specifying that namespace.The last attribute of the XML, xmlns="http://www.dealerlink.us" defines the default namespace of the document as http://www.dealerlink.us.You can fix that by prefixing...

How to create Crystal Report with query by linq

7 Nov 2011 by Sergey Alexandrovich Kryukov

This is what it is: you cannot use nullable types. You did not provide declaration of the type of p but by some its members in your code I can guess their declarations are like this:int? Year;int? TermNo;//maybe uint? ulong? or something like thisOtherwise comparison with null I...

Wondering what exams will help me gain good employment.

7 Dec 2011 by Ganesan Senthilvel

Since .NET 4.0 is the latest framework, you should appear for 70-515 web based development in .NET 4.0

Get a count of items with Linq

19 Dec 2011 by Wendelius

You can use grouping for that. See: http://msdn.microsoft.com/en-us/library/bb896250.aspx[^]For example: var dataSource = (from t in context.Tags group t by t.Description into t_group select new { Name =...

how to make my wpf project speed

2 Jan 2012 by OriginalGriff

I'm sorry to tell you, but we can't help.The problem is that there are so many things that could be slowing down your software, that to give you any concrete results, we would have to give you such a massive list of generalities that you would have to wade through it for hours looking for...

how to make my wpf project speed

2 Jan 2012 by Espen Harlinn

As you have DevExpress, why not use Xpo[^]?You should also take a look at DXGrid: Server Mode[^]The DXGrid supports a binding mode designed to work with large datasets. This is called server mode. With this mode, even if the grid control is connected to a data store containing millions...

Alias column names for a linq query

3 Jan 2012 by Wendelius

You should be able to simply define an alias without any extra characters as long as the names of the aliases conform to C# naming rules. For example, try the following:var q = from a in Number join b in Dupnum on a.ID equals b.ID select new ...

Select Persons from Index N to Index M

4 Jan 2012 by Shahin Khorshidnia

Ok, for example you have a collection of person :List PersonList = new List(); Person person1 = new Person() { Name = "John" }; Person person2 = new Person() { Name =...

Select Persons from Index N to Index M

4 Jan 2012 by fjdiewornncalwe

Shahin's answer will help your performance issue as his method will quite simply be more efficient.However, you may have a bigger root issue. If your list of persons is being loaded from the database, then I would suggest that your paging be done on the db query side. Your performance issue is...

Duplicate Notifier for a List using ObservableCollection

7 Mar 2012 by Sunil_Sebastian

Duplicate Notifier for a List using ObservableCollection.

Excuting a query in linq

25 Apr 2012 by VJ Reddy

The following LINQ query can be used to obtain the above resultsvoid Main(){ DataTable accData = new DataTable(); accData.Columns.Add("Date",typeof(DateTime),null); accData.Columns.Add("Credit",typeof(double),null); accData.Columns.Add("Debit",typeof(double),null); ...

How to write a ling query for group by

17 May 2012 by VJ Reddy

Introduce a where clause to remove the empty strings as followsvar Serialnumberentered = from a in serialNumbercheck//For .NET 2.0 and 3.5 where a == null ? false : a.Trim() != string.Empty //or where (a ?? "").Trim()!= string.Empty ...

Flat Resultset to Treeview Hierarchy

31 May 2012 by VJ Reddy

The above data can be converted into a heirarchial data source with XML data using LINQ with GroupBy extension method, and then it can be bound to the TreeView as shown below:protected void Page_Load(object sender, EventArgs e){ DataTable dt1 = new DataTable("DataTable1"); ...

Word wrap without cutting words

7 Jun 2012 by Matt T Heffron

This is an alternative for "Word wrap without cutting words"

how to use inner join in linq query

13 Jun 2012 by Vani Kulkarni

Hello, Please go through the link given below:http://stackoverflow.com/questions/37324/what-is-the-syntax-for-an-inner-join-in-linq-to-sql[^]http://msdn.microsoft.com/en-us/library/bb397941.aspx[^]

how to use inner join in linq query

13 Jun 2012 by AmitKumar89

Hi,Please refer the links:http://stackoverflow.com/questions/525194/linq-inner-join-vs-left-join[^]http://msdn.microsoft.com/en-us/library/bb397941.aspx[^]http://msdn.microsoft.com/en-us/library/bb397676.aspx[^]All the best.--AK

What is the problem of using a lot of relations in database ?

18 Sep 2012 by Sergey Alexandrovich Kryukov

Please see my comment to the question. Your question might be based on some your misconception or maybe the conception you do not explain.The relationships should not really be quantified by the total number of them or something like that. And "a lot of relations" does not have to mean "a...

entity-framework