One of the many samples released for Visual Studio 2010 Beta 1 that you should be aware of are examples of WPF data binding against Entity Data Models. You can find some easy to follow samples here: http://code.msdn.microsoft.com/WPFDatabinding

This sample demonstrates how to create a WPF Forms solution that checks user input with validation code, demonstrates common controls such as DataGrid and ComboBox, and shows typical data manipulation including create, read, update, and delete. The sample solution is available in both Visual Basic and C# and is intended for use with Visual Studio 2010 Beta 1 and with the .NET Framework 3.5.  In the future, we will release a sample that performs with the .Net Framework 4.0 Beta.

Check out the VS Data Team blog for more information on WPF data-binding and Karl’s blog on a great WPF sample series.

Enjoy!

Kathleen McGrath has started a series where she takes Visual Studio 2010 walkthroughs and demonstrates them with a screen-cast each week on Channel 9. If you’re just digging into the VS2010 Beta you should definitely check these out to help get you started on all the new features.

Don’t miss my favorites so far…

• Video: Deploying Multiple Office Solutions in a Single ClickOnce Installer
• Video: Auto-Implemented Properties in Visual Basic 2010

Enjoy!

Visual Basic 10 (in Visual Studio 2010) is getting a new feature called Collection Initializers which contains the same functionality as the C# 3 feature but it takes it one step further. Let me show you what I mean.

Visual Basic 9 (in Visual Studio 2008) already has Object Initializers which come in handy when you want to quickly populate some public properties on an object. For instance, say I have a class called Student that has Name (string), Age (integer) and Score (integer) public properties. In a single line of code I can initialize a new object and specify only the properties I want to set as long as the Student class has a default constructor:

Dim s As New Student With {.Age = 29, .Name = "Beth"}

Object Initializers are also used often in LINQ statements when you want to project selected values into your own named objects:

'produces a collection of Student objects from a LINQ query. IEnumerable(Of Student):
Dim myStudents = From contact In ContactList _
                 Select New Student _
                        With {.Age = contact.Age, _
                              .Name = contact.Name}

However if you want to create a Generic.List(Of Student) in Visual Basic 9 you can’t do it in one line. A trick is to use Array Initializers to populate an array with objects using Object Initializers and then call ToList to create the generic List:

'Use Array & Object Initializers to create an array of Students
Dim s As Student() = {New Student With {.Age = 10, .Name = "Beth"}, _
                      New Student With {.Age = 11, .Name = "Alan"}, _
                      New Student With {.Age = 12, .Name = "Robert"}, _
                      New Student With {.Age = 13, .Name = "Jenn"}}

'Convert the array to a Generic.List
Dim studentList As List(Of Student) = s.ToList()

But this is really less than ideal because of the casting. What we really want to do is have the objects automatically added to the list via the List.Add method. Collection Initalizers do just that. They are basically just a shorthand syntax for calling the Add method explicitly on the collection.

Collection Initializers in C# 3  look like this:

var nums = new List<int> { 1, 2, 3, 4, 5 };

var studentList = new List<Student> {new Student {Age = 10, Name = "Beth"}, 
                                     new Student {Age = 11, Name = "Alan"}, 
                                     new Student {Age = 12, Name = "Robert"}, 
                                     new Student {Age = 13, Name = "Jenn"}};

Visual Basic 10 now also provides this feature using the From keyword (note, VB 10 does not require underscores and provides a new syntax coloring):

Dim nums As New List(Of Integer) From {1, 2, 3, 4, 5}

Dim studentList As New List(Of Student) From
    {New Student With {.Age = 10, .Name = "Beth"},
     New Student With {.Age = 11, .Name = "Alan"},
     New Student With {.Age = 12, .Name = "Robert"},
     New Student With {.Age = 13, .Name = "Jenn"}}

What’s happening in these cases is the compilers are looking for the existence of an Add method on the collection and calling that for you. However in VB 10 they took it a step further. In C# 3 the Add method must be an instance method on the collection but in VB 10 you can provide your own Extension Method and provide your own functionality. For instance, we can make the calling syntax even simpler by writing an extension method that does the object initialization as well:

<Runtime.CompilerServices.Extension()>
Sub Add(ByVal list As List(Of Student),
        ByVal age As Integer,
        ByVal name As String)

    list.Add(New Student With {.Age = age, .Name = name})
End Sub

Now we can initialize our Generic.List(Of Student) like so:

Dim studentList As New List(Of Student) From
    {{10, "Beth"}, {11, "Alan"}, {12, "Robert"}, {13, "Jenn"}}

You can also omit the From keyword and pass the collection initialization directly to the constructor of the Generic.List because the List has an overloaded constructor that accepts an IEnumerable:

Dim nums As New List(Of Integer)({1, 2, 3, 4, 5})

So the rule of thumb is, use From to call the Add method or you could pass directly to call the constructor if it accepts an IEnumerable. Passing values this way directly isn't as efficient though because an array is created first and then passed to the constructor (which then loops through and calls Add internally). Using the From keyword calls the Add method directly for you.

Pick up a copy of the Visual Studio 2010 Beta 1 and try it out for yourself.

Enjoy!

Joe Stagner, ASP.NET/Web community guru, has just launched a new podcast on MisfitGeek.com. In this first episode he talks with Scott Hunter, a Senior Program Manager Lead on the ASP.NET Team, about the future of Web Forms and how Web Forms compares with ASP.NET MVC. He also talks about web data controls and compares the web forms development experience to the ease of VB6 forms development which is interesting to me.

Episode #1 - Scott Hunter on the Future of Web Forms

This Joe’s first podcast and he’s taking suggestions on how to make it better so please send him comments here.

Enjoy!

Last week Alan and I headed up to Yosemite National Park with my sister and her boyfriend and Robert Green (VSTO MVP and log-time friend) and his wife, Colette. We had an absolutely fabulous time and I recommend that everyone in the world come visit. And believe me, Memorial Day weekend it seems like everyone in the world is doing just that! ;-) Luckily we stayed the whole week so after Sunday people left the valley and we were left with a peaceful vacation.

The falls are full, the Merced river is flowing high and the flowers are all in bloom.

We all agreed that heaven must look something like this. This is the view from inspiration point just as you come through the Wawona tunnel – showing Half Dome at the east end of the Yosemite Valley, El Capitan to the North and Bridal Vail Falls to the South (click to enlarge).

And here’s Half Dome (left), Vernal Falls (lower) and Nevada Falls (upper) from Glacier Point. Stunning. We hiked down the 4-mile trail from Glacier Point down to the valley with views of Yosemite falls (first and fourth picture above) the whole time.

We stayed in a cottage in Yosemite West and did a lot of day hiking and long valley walks. The highlight was Robert, Colette and I hiked 16.4 miles up to the top of Half Dome and back on Tuesday which took us about 10 hours. You hike up to Vernal then Nevada falls first and then a long walk up the John Muir trail through Little Yosemite Valley and cut over onto the Half Dome trail. I’ve done it once before about 15 years ago but I didn’t remember how hard those cables were, especially coming down, but we did it!

Yosemite only takes about 3.5 hours to drive there from my house so I’m already thinking about our next long weekend….

I really enjoyed this vacation.