The Label control

The screenshot shows our sample dialog as it looks when the Alt key is pressed. Try running it, holding down the [Alt] key and then pressing N and M. You will see how focus is moved between the two textboxes.

So, there's several new concepts here. First of all, we define the access key by placing an underscore (_) before the character. It doesn't have to be the first character, it can be before any of the characters in your label content. The common practice is to use the first character that's not already used as an access key for another control.

We use the Target property to connect the Label and the designated control. We use a standard WPF binding for this, using the ElementName property, all of which we will describe later on in this tutorial. The binding is based on the name of the control, so if you change this name, you will also have to remember to change the binding.

Using controls as Label content

As already mentioned, the Label control allows you to host other controls, while still keeping the other benefits. Let's try an example where we have both an image and a piece of text inside the Label, while also having an access key for each of the labels:

<Window x:Class="WpfTutorialSamples.Basic_controls.LabelControlAdvancedSample"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="LabelControlAdvancedSample" Height="180" Width="250">
	<StackPanel Margin="10">
		<Label Target="{Binding ElementName=txtName}">
			<StackPanel Orientation="Horizontal">
				<Image Source="http://cdn1.iconfinder.com/data/icons/fatcow/16/bullet_green.png" />
				<AccessText Text="_Name:" />
			</StackPanel>
		</Label>
		<TextBox Name="txtName" />
		<Label Target="{Binding ElementName=txtMail}">
			<StackPanel Orientation="Horizontal">
				<Image Source="http://cdn1.iconfinder.com/data/icons/fatcow/16/bullet_blue.png" />
				<AccessText Text="_Mail:" />
			</StackPanel>
		</Label>
		<TextBox Name="txtMail" />
	</StackPanel>
</Window>

This is just an extended version of the previous example - instead of a simple text string, our Label will now host both an image and a piece of text (inside the AccessText control, which allows us to still use an access key for the label). Both controls are inside a horizontal StackPanel, since the Label, just like any other ContentControl derivate, can only host one direct child control.

The Image control, described later in this tutorial, uses a remote image - this is ONLY for demonstrational purposes and is NOT a good idea for most real life applications.

Summary

In most situations, the Label control does exactly what the name implies: It acts as a text label for another control. This is the primary purpose of it. For most other cases, you should probably use a TextBlock control or one of the other text containers that WPF offers.