How to do it...

In the following steps, we will build a simple application that will create and execute a multi trigger based on some conditions and change the Foreground and Background properties of the TextBox controls:

1. Open the MainWindow.xaml file.
2. Replace the default Grid panel with a vertical StackPanel.
3. Add two TextBox controls inside the panel and set their Text property to represent some text. Here's the XAML that we will be using in this example:

<StackPanel> 
    <TextBox Text="Focus your cursor here" 
             FontSize="20" 
             HorizontalAlignment="Stretch" 
             VerticalAlignment="Center" 
             Height="30" 
             Margin="4"/> 
 
    <TextBox Text="Focus your cursor here" 
             FontSize="20" 
             HorizontalAlignment="Stretch" 
             VerticalAlignment="Center" 
             Height="30&quot...