Learning C# 3.0

Your First WPF Application

The best way to learn WPF is to start off with a traditional Hello World application. From within C# Express or Visual Studio, create a new project. When the New Project dialog box appears, select WPF Application as the project type, and name the project "Hello WPF”.

Visual Studio will create the project and open a WPF editing window for you, as you can see in Figure 19-1.

Notice the split window in the middle of the IDE. It shows a visual representation of your form on the top, called the Design view, and the XAML markup on the bottom.

Before you do anything else, take a look at the code that’s automatically created for you in the XAML window. It looks something like this:

<Window x:Class="Hello_WPF.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <Grid>

    </Grid>
</Window>

The first thing you see is the opening tag for the Window element itself. That element contains a reference to the Class for the application, created by default. The x refers to the default namespace for this application. (You can change the namespace if you like, but x is the default.) The xmlns properties define the namespace for the application, by referring to the XML schema for WPF, as defined by Microsoft. In short, this is where you’ll find the specification of the elements that you can use in this file. You don’t really need to worry much about this for the moment, ...