#300 – Button is a ContentControl

Button is a ContentControl, which means that it can contain exactly one child control.  The child element can be any .NET object.

A simple string is the most common content for a Button.

        <Button Content="Click me" Click="Button_Click"/>

Examining the Button control at runtime, you can see that its stores an instance of a string in its Content property.  Also note that the base type of Content is object, meaning that the button could store any .NET object as its content.

Here’s a Button that contains a single Ellipse control as its content:

        <Button Click="Button_Click" Width="140" Height="80">
            <Ellipse Fill="PaleGreen" Stroke="Blue" StrokeThickness="5" Width="120" Height="60"/>
        </Button>

And here’s a Button that uses a StackPanel to host several child controls.

        <Button Click="Button_Click" Width="140" Height="120">
            <StackPanel>
                <Ellipse Stroke="Blue" StrokeThickness="5" Width="120" Height="60"/>
                <Label Content="Name my ellipse"/>
                <TextBox />
            </StackPanel>
        </Button>