Recent articles

On this page you will find an overview of all articles that I have written myself. The more recent articles deal with software development with .NET (C#, Visual Studio, VSTS, Azure, LINQ, Entity Framework, Web services, WPF, Silverlight, ...) in particular. The older articles were often written for the purposes of courses or demonstrations at my computerclub and these articles are mostly about Delphi, PHP, databases, Javascript, Windows, Office, Multimedia applications, Atari, ...

Below the 25 most recent articles are listed. Use the left panel to filter the more than 110 articles by category. These articles can be used freely for personal use. Placing the full articles on other websites is not allowed without the permission of the author.

Documentation Delphi TscExcelExport component
Documentation, release notes and many examples of the Delphi VCL TscExcelExport component (in PDF format). The last version of this component works in Embarcadero Delphi 10 Seattle, 10.1 Berlin, 10.2 Tokyo and 10.3 Rio and it supports all Excel versions from Office 97 to 2019.
- English - Delphi, Excel
.NET - Customized tasks in VSTS builds
The Microsoft Visual Studio Team Services (VSTS) have a totally new way of creating build definitions. There are many available tasks right out of the box. In this article I will cover some techniques how to customize the build process. I will show you how to implement PowerShell scripts and work with environment variables and arguments, how to load custom C# .NET assemblies and how to create extensions and upload them to VSTS.
- English - .NET, VSTS
.NET - Azure Management Libraries
This article contains a lot of C# .NET examples how to use the Microsoft Azure Management Libraries to automate, deploy, and test cloud infrastructure easily. It includes examples for creating and deleting Azure clouds services, SQL databases, storage, websites, services bus, configuring websites, starting and stopping virtual machines, …
- English - .NET, Azure
.NET - ASP.NET WebAPI services and Windows Integrated Authentication
A detailed article about ASP.NET WebAPI 2.2 REST services and Windows Integrated Authentication (WIA) for intranets. How does it work and how to configure windows authentication in your .NET server project, in IIS (Express) and in the webbrowsers. And finally I will show some examples how to implement .NET and HTML/Javascript clients which consume the service.
- English - .NET, Web services
.NET - Spatial Data in Entity Framework 5.0
In Entity Framework 5.0 spatial data types are supported so now we can create Linq queries to query nearby locations, calculate distances and check if locations intersect with an area. This articles demonstrates how to insert and update locations with latitude and longitude coordinates and how to query them in different ways.
- English - .NET, Entity Framework, Geography
.NET - Customize WCF RIA Services code generation
SP1 of Visual Studio 2010 and the new WCF RIA Services Toolkit makes it possible for you to implement you own code generation classes that can manipulate the client code generation of WCF RIA Services. In this article I will describe how the code generation works and I will demonstrate some scenarios and ideas were customizing the generated code is a nice technique to extend your own framework.
- English - .NET, Web services, Silverlight
.NET - Functions in the Entity Framework 4.0: part 3
In this third article about the Entity Framework 4.0 I will explore some SqlClr features and show how to call custom .NET functions and aggregates in LINQ to Entities queries.
- English - .NET, Entity Framework, Database
.NET - Functions in the Entity Framework 4.0: part 2
In this second article about the Entity Framework version 4.0 user defined functions and the new Model Defined Functions will be explored. Based on a series of simple examples I will show how to map UDF's and Entity SQL expressions to Model Defined Functions and how to call them in LINQ to Entities queries.
- English - .NET, Entity Framework, Database
.NET - Functions in the Entity Framework 4.0: part 1
The Entity Framework together with LINQ to Entities are very powerful technologies to access and manipulate data from a database. But when you need to gain performance or need extra security, stored procedures and user defined functions are often required. In this first article in a series of three I will focus on how to use stored procedures in the Entity Framework 4.0.
- English - .NET, Entity Framework, Database
.NET - Silverlight 4 design-time features for ViewModels
Visual Studio 2010, .NET 4.0 and Silverlight 4 offer a lot of new features. I like all the new features but I was especially interested in improvements that could help my current developments which are based on a M-V-VM architecture with ViewModels and a lot of bindings with UI controls. In this article I will focus on the improved design-time features. Along the way I will show a lot of screenshots and try to cover some other new Silverlight 4 features.
- English - .NET, Silverlight, Visual Studio
.NET - Advanced databinding with ViewModels in Silverlight
Silverlight and RIA Services are great technologies and the Model-View-ViewModel (M-V-VM) pattern is a nice approach to keep UI and logic separated. But using the combination of view models with item controls, dataforms and commands can be a laborious task because the databinding features in Silverlight are quite limited. In this article I will demonstrate how binding with ViewModels can be improved by using the BindingHelper class and by creating your own command behaviors.
- English - .NET, Silverlight
.NET - First look at WCF RIA Services
A few months ago Microsoft released the first preview of .NET RIA Services. This new framework promises to simplify building n-tier Line of Business (LoB) applications by providing patterns, components and tools to build services, query data, handle CRUD operations, resolve concurrency, manage data validation, ... In this first article I will focus on the current limitations and I will offer you some of my workarounds and tips.
- English - .NET, Web services, Silverlight
.NET - New connection providers in LINQPad
LINQPad was introduced in 2007 and nowadays it is a very mature tool which should be in the toolbox of every .NET developer. Version 1.35 offers new connection providers and it has native support for LINQ to SQL and the ADO.NET Entity Framework data models. It also provides new query types like SQL and Entity-SQL. In this small article I will highlight some of the new features.
- English - .NET, LINQPad, LINQ, Entity Framework
.NET - Sharing source code between .NET and Silverlight
A common problem when developing Silverlight applications is how to share classes and in particular (Entity Framework) entities which are compiled for the full .NET framework in a Silverlight application. Silverlight is a browser plugin and a subset of the full .NET framework. Therefore Visual Studio does not allow referencing .NET assemblies from your Silverlight application. In this article I will demonstrate a very simple technique to share source code and it will give several real world examples and some handy tips.
- English - .NET, Silverlight, Entity Framework
.NET - Cleaning up and organizing Outlook mailboxes
This small article contains a few C# scripts which can be executed in LINQPad to clean up and organize Outlook mailboxes. If you want to keep Outlook performing as fast as possible and to reduce the size of mailboxes then these scripts and my OutlookProvider component can simplify this job.
- English - .NET, Office, Outlook, LINQ, LINQPad
.NET - ADO.NET Entity Framework : Metadata extension methods
In addition to my article about querying the metadata of the ADO.NET Entity Framework I have implemented several extension methods that utilize this metadata. This article will describe a set of extension methods which can be used to extend the standard Entity Framework classes (ObjectQuery, EntityObject, ObjectStateManager, ...).
- English - .NET, Entity Framework
.NET - Querying Excel worksheets with LINQ
A while ago I was looking for a way to query Excel with LINQ. I needed a simple solution that allowed me to query tables in Excel worksheets in a tool like LINQPad. This article will describe how I implemented my ExcelProvider and it will demonstrate its features by giving an example of a LINQ query and the result in LINQPad.
- English - .NET, Office, Excel, LINQ, LINQPad
.NET - ADO.NET Entity Framework : Querying metadata
A few months ago I posted several articles about the ADO.NET Entity Framework beta 3. In the meanwhile the Entity Framework has been officially released and a lot of resources about this technology have become available. In the last few weeks I have been taking a closer look at the metadata services. This article will demonstrate 20 examples which use LINQ to query the metadata collections of the ADO.NET Entity Framework. These queries can be used to examine the structure of your Entity Data Model or to get statistics about it.
- English - .NET, Entity Framework, LINQ
.NET - LINQ AsHierarchy() extension method - part 2
A few months ago I published an article about my LINQ AsHierarchy extension method. This extension method can be used to convert a flat collection of records to a hierarchical structure of nested collections. I got a lot of enthusiastic responses and questions so I decided to improve this technique a little further. This new article will describe the new features and demonstrates how to use the LINQ to Objects and the new LINQ to SQL AsHierarchy extension methods.
- English - .NET, LINQ, Entity Framework, LINQ to SQL
.NET - Generic custom WPF/Silverlight value converters
Data binding is one of the most powerful features of WPF/Silverlight. It allows developers to achieve more with less code. However, when building user interfaces with WPF/Silverlight, you often need to create your own value converters. A common mistake is to implement custom value converters for each and every binding that requires one. Of course value converters can be generalized an re-used. In this article I will show you the source code of my library of generic custom value converters and I will demonstrate in which scenarios you can use them.
- English - .NET, WPF, Silverlight
.NET - Using the Google Maps HTTP geocoding service
This article will demonstrate how to use the Google Maps HTTP geocoding service and how to handle REST services and XML in general. The Google Maps service can be used to retrieve the latitude, longitude and a lot of other geographical data from a given address.
- English - .NET, Geography
.NET - UI automation with the WPF UIAutomation framework
WPF UIAutomation is a framework from Microsoft to automate Windows applications. In this article I will demonstrate a lot of features (invoking button clicks, focusing controls, entering data, sending keystrokes, subscribing to events, ...) and compare it with the open-source project White.
- English - .NET, UI Automation, WPF, WinForms
.NET - UI automation with the White framework
This short article covers the most important features of the open-source White framework and the Microsoft UISpy tool. White can be used for UI automation and my C# .NET application demonstrates how to automate the Windows calculator by sending keystrokes, clicking on buttons and menus, pressing function keys, accessing textboxes, ...
- English - .NET, UI Automation, WPF, WinForms
.NET - LINQ AsHierarchy() extension method - part 1
This article explains how to convert data from a self referencing table (adjacency model) to a hierarchy of nested collections (nested set model). The new LINQ AsHierarchy() extension method can be used to convert data and bind it to WPF TreeViews.
- English - .NET, LINQ, Entity Framework, LINQ to SQL
.NET - WPF ProcessingControl and BackgroundWorker
This small article about the Windows Presentation Foundation will demonstrate how to use a WPF ProcessingControl and a BackgroundWorker thread to create responsive user interfaces and how to give visual feedback about the progress.
- English - .NET, WPF
.NET - ADO.NET Entity Framework & LINQ to Entities - part 3
In this third part of my series of articles about the ADO.NET Entity Framework I will demonstrate how to add and modify data, use change tracking and handle concurrency conflicts. I have also implemented a Dump() extension method which can be useful for displaying all change tracking information.
- English - .NET, Entity Framework, LINQ
.NET - Modeling PowerToys for Visual Studio 2008
A new version of the open-source PowerToys for the Class Designer and Distributed System Designer has been released. These add-ins provides additional functionality for the Visual Studio Class Designer, such as HTML/XML export, new creation commands, filtering commands, formatting commands, a pan/zoom window, a documentation window, a floating properties window, ... This small post describes how to install it and shows a screenshot which highlights almost all features.
- English - .NET, Visual Studio, Tools
.NET - Background color problem with WinForms and WPF
This post briefly describes how to integrate a WPF user control in a Windows Forms application. It also provides a workaround to solve the background color problem of the ElementHost class. This workaround will demonstrate how you can map properties between Windows Forms controls and WPF UI elements.
- English - .NET, WPF, WinForms
.NET - ADO.NET Entity Framework & LINQ to Entities - part 2
Second part of my series of articles about the ADO.NET Entity Framework. This article covers a few handy testing and learning tools like eSqlBlast and LINQPad. It also describes a few techniques on how to view the generated T-SQL statements when executing Entity SQL or LINQ to Entities queries.
- English - .NET, Entity Framework, LINQPad, LINQ
.NET - ADO.NET Entity Framework & LINQ to Entities - part 1
A few weeks ago Microsoft released Beta 3 of the ADO.NET Entity Framework (EF). The Entity Framework looks like an interesting technology which is more powerful and advanced than LINQ to SQL. I have created a small tutorial on how to start with the Entity Framework using the Northwind sample database. This first article covers the Entity Data Model (EDM), Entity SQL and LINQ to Entities. I will try to compare EF to LINQ to SQL if possible.
- English - .NET, Entity Framework, LINQ
.NET - LINQ to SQL - part 4
Fourth part of this series of articles about LINQ to SQL (.NET 3.5). This article shows the features of the 2 provided visualizers (LINQ to SQL Visualizer & Expression Tree Visualizer), the use of the Refresh method and how to create dynamic strong-typed Where- and OrderBy-clauses. Powerful expression trees can be created easily by using the PredicateBuilder class.
- English - .NET, LINQ to SQL, LINQ
.NET - Mole Visualizer for Visual Studio
Last week version 4 of the Mole Visualizer for Visual Studio was released. Mole is a great visualizer while debugging WPF, WinForms and WCF applications. Mole does not only allow you to view objects and data, it also allows you to drill into properties and child objects. A lot of properties can be modified and the result is displayed in a live preview.
- English - .NET, Visual Studio, Tools
.NET - WPF/Silverlight treeviews and LINQ to SQL
A few examples about .NET WPF applications using LINQ to SQL. This article will describe how to create nice looking treeviews which are populated with data using LINQ to SQL (or LINQ to Entities). Of course resources, templates, styles, datatriggers, value converters, ... will be utilized. Most examples will also work with Silverlight.
- English - .NET, WPF, Silverlight, LINQ to SQL, LINQ
.NET - Performance comparison with Parallel Extensions .NET 3.5
First tests with the Community Tech Preview of the Parallel Extensions for .NET 3.5. A comparison between sequential and parallel execution is made on the basis of charts. PLINQ and the ParallelTask Library can surely improve the performance of .NET applications.
- English - .NET, LINQ
.NET - Display Outlook contact pictures in WPF application
In this article I will show you how to create a ValueConverter class which can be used in a WPF application to display the pictures of the Outlook contacts.
- English - .NET, Office, Outlook, LINQ, WPF