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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

(Linq and Nullable Values) OR (SQL ISNULL with LINQ)

4 Jan 2011 by Pranay Rana

(Linq and Nullable Values) OR (SQL ISNULL with LINQ)

.Net - Use The Framework

22 May 2010 by #realJSOP

Don't reinvent the wheel - use the one that's already on the cart.

.Net - Use The Framework

6 Apr 2010 by TheGreatAndPowerfulOz

The following is far easier to understand and use than the Outlaw's tip (IMHO).text = Regex.Replace(text, "screen_fadetimeout=\"[^\"\']+\"", "screen_fatetimeout="99");It has the following advantages:1. It is one line of code2. It is easier to read3. It is faster (note: XmlElement...

.NET Important Topics Summary - Code Examples

31 May 2016 by Yaseer Mumtaz

.NET interview questions and answers with real world examples and code snippets

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

A better way to count(*)

7 Jun 2010 by Lee Humphries

LINQ translates .count() to a SQL query that uses COUNT(*), but on large tables even count(*) can be too slow. Here's another way

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}')

A Generic ADO.NET Overlay to Simplify DB Calls to SQL Server and Oracle

12 Jan 2016 by shijo joseph

An ADO.NET Layer for SQL Server and Oracle which makes it easier for interfacing with database

A Pagination Solution using IEnumerable<T>

17 Jul 2014 by Marlon Hizole

An elegant approach to pagination

An Example of a (LINQ) Approach to Solve Recurring Problems

8 Mar 2021 by Basem AlShabani

How to solve recurring problems using LINQ

Auto Complete with jQuery Template Plugin and AJAX

6 Jul 2013 by sumit_kapadia

AutoComplete Texbox with comma separated insertions

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.

Automated Serializer for WinRT Platform

19 Aug 2014 by Alberto Nuti

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

Best way to use Entity Framework

14 Jan 2013 by Kundan Singh Chouhan

Simplest, best and most robust architecture.

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...

Build Dynamic Order by Clause in LINQ Query in C#

5 Jun 2022 by Ramesh Bevara

An overview of a helper class to build dynamic order by clause in LINQ query in C#

Build Where Clause Dynamically in Linq

6 May 2014 by Fitim Skenderi

Build where clause dynamically in Linq

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

C# Linq GroupBy ExtensionMethod Explained

17 May 2018 by Clifford Nelson

This tip provides examples of how to use the different arguments of the Linq GroupBy extension method.

Calendar of Events in Windows Phone

15 Oct 2012 by Houssem Dellai

Developing a Windows Phone app step by step

Case Sensitive Comparison of Datatables using LINQ

22 Mar 2015 by Mathi Mani

In this tip, we will see how to perform case sensitive comparison of datatables using LINQ

Cast an IEnumerable to an IEnumerable(T)

22 Dec 2012 by Thomas Daniels

In this tip, I tell you how to cast an IEnumerable to an IEnumerable(T)

Change Tracking an ObservableCollection

6 Jul 2018 by Daniel Ziegelmiller

How to track changes in the ObservableCollection displayed in a WPF DataGrid

CheckBoxList ASP.NET MVC3

8 Sep 2012 by suhas.shiv

Custom CheckBoxList in ASP.NET MVC3

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

Compare two datatable using LINQ Query

12 Mar 2012 by Ramanujam Shankar

Convert Linq Query Result To DataTable

5 Apr 2010 by Rami Shareef

Sometimes you need the Linq query result as datatable (I need it today)Use this: public DataTable ToDataTable(System.Data.Linq.DataContext ctx, object query) { if (query == null) { throw new ArgumentNullException("query"); ...

Convert LINQ to Entity Result to a DataTable

22 Mar 2011 by Mohammad Al Hoss

entity-framework

Convert LINQ to Entity Result to a DataTable

20 Apr 2011 by jonx

Very good stuff. Learned me a lot about how to access to the physical structure of the query.There is also a CopyToDataTable : http://msdn.microsoft.com/en-us/library/bb386921.aspx[^]And for the record here is a C# version:protected DataTable EntityToDatatable(IQueryable Result,...

entity-framework

Convert XML to Object using LINQ

17 Apr 2012 by Naufel Basheer

Convert complex XML to an object using LINQ

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

24 Jan 2012 by Mikhail-T

A short one-line way to convert Array or List of any data into custom string via LINQ

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

18 Jan 2012 by wgross

I would just use:string.Join(",", cities.Select(c=>c.Name))Since Version 4 of the Framework there is an overloaded versions of string.Join for IEnumerable too. It uses a StringBuilder internally and doesn't insert a seperator after the last element as well.I could't find the Join method...

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));

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

24 Jan 2012 by Richard Deeming

If you're stuck with .NET 3.5, you can use the Aggregate extension method[^]:string cities_string = cities.Aggregate(new StringBuilder(), (sb, c) =>{ if (0 != sb.Length) sb.Append(", "); sb.Append(c.Name); return sb;}, sb => sb.ToString());

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

4 Feb 2012 by jarvisa

string.Join(",...

Count number of occurences of a value in a List using LINQ

29 Mar 2010 by The Manoj Kumar

Did you ever face a situation where you want to calculate total number of occurrences of a value in a List object?What approach did you used for it?Did you ever try LINQ for the same? Yes, you can use it. Just look at the example below:class Program{ static void Main() ...

Create Linq to SQL connection with select, insert, delete, update

6 Feb 2011 by SuhasHaridas

Create Linq to SQL connection with select, insert, delete, update

SQL-Server-2005

Creating Func delegates using TextToCalcExpression

16 Mar 2012 by Carlos Conceição

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

Creating Presentation Objects with PresentationMapper

29 Apr 2015 by HUONG Minh-Luong

How to use PresentationMapper to generate presentation objects

CRUD in ASP.NET MVC 4 with KnockOut.JS

20 Jan 2016 by Indresh_Prajapati

This tip will help beginners to implement CRUD operations in ASP.NET MVC 4 with scripting language as KnockOut and Database as MS SQL 2008R2.

Cumulating values with LINQ

26 Jul 2012 by Wendelius

This tip describes few examples how ro cumulate values using an extension method with LINQ

Cumulating Values with LINQ

27 Jul 2012 by Matt T Heffron

This is an alternative for "Cumulating values with LINQ"

Cumulating values with LINQ

27 Jul 2012 by Wendelius

This is an alternative for "Cumulating values with LINQ"

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.

DataLoadOptions and How to use in Compiled Linq query

13 Nov 2011 by Pranay Rana

DataLoadOptions and How to use in Compiled Linq query

DataReader into IEnumerable with C#

4 Nov 2013 by Jaume González

How to convert any datareader into generic list.

6 Feb 2019 by Maciej Los

C# helper class to convert date into words

Determine selected RadioButton in a Group of RadioButtons

5 Mar 2010 by karenpayne

This code permits a developer to determine if a radio button is selected in a container such as a panel or GroupBox using syntax similar to TryParse.Requires Requires Framework 3.5 or higherExamplePrivate Sub Button1_Click() Handles Button1.Click Dim SelectedButton As New...

Duplicate Notifier for a List using ObservableCollection

7 Mar 2012 by Sunil_Sebastian

Duplicate Notifier for a List using ObservableCollection.

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

Dynamic Sorting in LINQ

8 Oct 2013 by Thomas Corey

Dynamically sort query results using LINQ expressions and reflection.

Dynamically Build LINQ to SQL Classes at Runtime

13 Sep 2013 by oryan

Dynamically build Linq2Sql classes based off SQL table

Dynamically creating a predicate delegate

29 May 2014 by Randy Kroeger

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

Dynamically generate a LINQ query with a custom property

23 Mar 2012 by Elvis Begluk

Dynamically generate LINQ query with a custom property.

Easy Method to Split Large XML File Using LINQ to XML

23 Jun 2014 by ravgill66

Use LINQ to XML to split an XML file into a number of smaller files

EBCDIC to ASCII Converter

18 Feb 2018 by Max Vagner

Converting mainframe EBCDIC to ASCII format

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

EF Remove If Exists

12 Apr 2014 by Robert Lindblom

Removing entity if it exists

Effective Paging Using LINQ (Sample Code)

13 Sep 2012 by Sarvesh Kushwaha

Binding Gridview (or any other data control) with effective paging using LINQ

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

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

EntityWorker.Core - An Alternative to Entity Framework

3 Oct 2018 by Alen Toma

EntityWorker.Core - an alternative to entity Framework

Excel To DataBase Table

3 Nov 2012 by Sarvesh Kushwaha

Export Excel to SQL database table (Sample Code)

Expressmapper - The New .NET Mapper!

13 Jul 2015 by Yuriy Anisimov

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

Extended ORM generated class

24 Oct 2011 by Pranay Rana

Extended ORM generated class

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

Filtering records from List similar to Sql IN Operator using LINQ

27 Feb 2012 by Greg Sipes

An alternate solution.

Find Odds Out in a Generic List

22 Oct 2012 by Rajesh Kariyavula

Find the Odds Out in A Generic List

Finding Items in a Collection that Match one of...

19 Oct 2016 by Midi_Mick

Use LINQ to get the members of a collection that match the members of another collection

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.

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.

Flatmapper

9 Feb 2016 by João Matos Silva

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

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

Formatting unformatted XML string in LINQ – Code snippets

18 Oct 2011 by CodingLover

How to format unformatted XML string easily with LINQ.

Generate code from database

7 Jun 2011 by User-Rock

LINQ to SQL

Generate Game List Based on List of Players in C#

2 Sep 2014 by Andre van Dun

Generate game list based on list of players in C#

Generate XML in ASP.NET MVC5 and AngularJs using Database Value

16 May 2016 by Md._Mehedi_Hasan

This tip will help you to generate .xml file in AngularJs and ASP.NET MVC5 using XElement of C#.

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

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

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

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.

Get basic intuition about how LINQ works

8 Nov 2011 by Delashmate

Deep Look in the basics of LINQ

15 Oct 2021 by BillWoodruff

Create collections of #n sized elements from arrays, lists, and string

Get LINQ GetCommand Parameters

5 Dec 2012 by moosa pourghafari

Get LINQ GetCommand parameters.

Get Nested Property value using reflection and Linq.Expression

20 Nov 2011 by Massimiliano Peluso "WeDev Limited"

Get Nested Property value using reflection and Linq.Expression

Get Nested Property value using reflection and Linq.Expression

8 Apr 2011 by cechode

Saw this a while back; it's simpler (dirty and wrong but... ):public static T Get(Func getDelegate, bool DefaultTOnNull = false, T defaultVal = null) where T : class{ T result = null; try { result = getDelegate(); } catch...

Get Selected CheckBoxes from container

24 Jan 2011 by karenpayne

Returns all checked Checkbox controls in a Windows Form container

Getting more from your enumerations

11 Dec 2012 by Gregory Gadow

With LINQ, you can retrieve an enumeration's metadata, such as its minimum and maximum values and whether it contains a given value.

Getting Property Name using LINQ

7 Feb 2010 by Arun Jacob

Sometimes we want to compare the property names like,if (e.PropertyName == "FirstName"){//Do Something}But this is not type safe. If we change the property name then this won’t work as expected and also it won’t throw compile time error. For getting property name for Type safe...

How to Attach object to a different data context

10 Feb 2010 by Dev_2580

For the last couple of days, working on my project for my studies I have struggled with this annoying issue regarding LINQ to SQL classes.When we update an entity within a DataContext, we can simple use something likecontext.Entity.Attach(updatedEntityInstance)The proplem is that...

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 capture the effect of LIMIT clause in MySql using LINQ

3 Feb 2011 by debolina.d

Limit the number of records that can be fetched from database based on its count like using the LIMIT clause in MySql

How to Convert LINQ Query to DataTable

3 Sep 2014 by debashishPaul

How to convert LINQ query to DataTable

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 fix "LocalDB - Requested Login failed"

20 May 2014 by Ed Nutting

How to fix LocalDB / SQL Server: "Cannot open database "XYZ" requested by the login. The login failed. Login failed for user ABC"

How To Insert Records Into A Table That Has No Primary Key, using LINQ to SQL?

12 Dec 2014 by karimbaig5

This tip provides an idea about how to insert a record into a table having no primary key using LINQ to SQL.

How to log your LINQ query

24 Oct 2011 by Pranay Rana

Log your LINQ query

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...

How to Return/Serialize JSON in VB.NET

23 Jan 2018 by The Myth

How to return Json in VB.NET in multiple ways

How to serialize list of linq entities (ex. from DBML)

10 Dec 2009 by EuGenius_Krivbass

Today I was trying to save list of entities those were generated by DBMLThis code shows how you can store your list in XML string and put it in ViewState, after that you get your list back.Using the CodeYou can use this code as you need.Here is class Serializatorpublic class...