I recently had a client ask how to retrieve a list of Active Directory Domains as he wanted to give a list to his user. Turns out this is very easy to do in .NET. All you have to do is add a Reference to the System.DirectoryServices DLL and add a using statement:

When you write a Windows Phone application you will most likely consume data from a web service somewhere. If that service returns data to you in a sort order that you do not want, you have an easy alternative to sort the data without writing any C# or VB code. You use the built-in CollectionViewSource object in XAML to perform the sorting for you. This assumes that you can get the data into a collection that implements the IEnumerable or IList interfaces.

In most database applications you will have foreign keys to express a relationship between one table and another. Many times this takes the form of a lookup table where you want the user to pick from a selection of items such as an Employee Type for an Employee record. You don’t want to have the user remember a number such as 1, 2, or 3, but instead they will pick from a list of the description that corresponds to these numbers such as “Manager”, “Project Manager”, or Employee. While you want to display these descriptions in a ComboBox, like that shown in Figure 1, you want to store the Employee Type ID number into your Employee table to make the data smaller and make it more efficient to join between the two tables.

In most database applications you will have foreign keys to express a relationship between one table and another. Many times this takes the form of a lookup table where you want the user to pick from a selection of items such as an Employee Type for an Employee record. You don’t want to have the user remember a number such as 1, 2, or 3, but instead they will pick from a list of the description that corresponds to these numbers such as “Manager”, “Project Manager”, or Employee. While you want to display these descriptions in a ComboBox, like that shown in Figure 1, you want to store the Employee Type ID number into your Employee table to make the data smaller and make it more efficient to join between the two tables.

This is a follow-up to my previous blog post on the Basics of MVVM in which I used Silverlight to illustrate how to use a basic MVVM design. I had so many emails asking for a WPF version, I decided to post this sample using WPF.

While training and consulting with clients around the country, I find that many developers still have trouble grasping the concept of Model-View-View Model (MVVM) as used in Silverlight or WPF. In this blog post I thought I would show two examples side-by-side to help you learn how to move from the more traditional model of development to MVVM.

Windows Phone does not yet support multi-tasking, however you can interact with some of the built-in applications on the phone from within your application. Depending on the application you call, you will either launch the application and pass in some data to the application, or you will launch the application and have some data returned. The former is called a launcher, while the later is called a chooser. In this blog post you will learn to call a chooser from your application and have that chooser return some data from the built-in application. The specific chooser for this blog post will be the PhoneNumberChooserTask as shown in Figure 1.

The Windows Phone does not support multi-tasking (yet), however you can call many of the built-in applications on the phone from your application. Depending on the application you call, you will either launch the application and pass in some data to the application, or you will launch the application and have some data returned. The former is called a launcher, while the later is called a chooser. In this blog post you will learn to call a launcher from your application. The specific launcher will be the SavePhoneNumberTask as shown in Figure 1.