What is the difference between the WPF TextBlock element and Label control?
WpfWpf Problem Overview
Visually both of the following snippets produce the same UI. So why are there 2 controls..
Snippet1
<TextBlock>Name:</TextBlock>
<TextBox Name="nameTextBox" />
Snippet2
<Label>Name:</Label>
<TextBox Name="nameTextBox" />
(Well I am gonna answer this myself... thought this is a useful tidbit I learnt today from Programming WPF)
Wpf Solutions
Solution 1 - Wpf
The WPF Textblock inherits from FrameworkElement instead of deriving from System.Windows.Control like the Label Control. This means that the Textblock is much more lightweight. The downside of using a textblock is no support for Access/Accerelator Keys and there is no link to other controls as target.
When you want to display text by itself use the TextBlock. The benefit is a light, performant way to display text.
When you want to associate text with another control like a TextBox use the Label control. The benefits are access keys and references to target control.
Solution 2 - Wpf
Label has an important focus handling responsibility.Its purpose is to allow you to place a caption with an access key. It has a Target property, which indicates the target of the access key. Like this...
<Label Target="{Binding ElementName=nameTextBox}">_Name:</Label>
<TextBox x:Name="nameTextBox" />
In the absence of the Target property, the Label control does nothing useful. You'll just hear a beep if you press the access key indicating 'unable to process request'
Solution 3 - Wpf
The two biggest reasons for the confusion regarding TextBlocks and Labels are Windows Forms and common sense.
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When you wanted to slap a small bit of text on your form in Windows Forms, you used a Label, so it follows (incorrectly) that you would do the same thing with a WPF Label.
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Common sense would lead you to believe that a Label is lightweight and a TextBlock isn't, when the opposite is true.
Note that you can put a TextBlock inside a Label.
Solution 4 - Wpf
With TextBlock we can easily have multi-line support I guess - using TextWrapping.
Using Label in such cases, e.g. displaying validation message, need to use <AccessKey> tags, which is less straight-forward than TextBlock.
On the other hand, using TextBlock not allow us to set the BorderBrush property.
So, to me, the two controls should be combined into a text-full-feature control.
Solution 5 - Wpf
Label takes all kinds of data inputs like String, Number etc... TextBlock, as the name suggests, only accepts a Text string.
Solution 6 - Wpf
Label can be used as an alternative to TextBlock for situations where minimal text support is required such as the label for a control. Using Label can be advantageous because it requires even less resources (lighter weight) then a TextBlock.