Display a Toolbar
<Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="WPF" Height="200" Width="300"> <DockPanel FocusManager.FocusedElement="{Binding ElementName=rtbTextBox}" LastChildFill="True"> <ToolBarTray DockPanel.Dock="Top"> <ToolBar Band="0"> <Button Command="ApplicationCommands.Cut" Content="Cut" /> <Button Command="ApplicationCommands.Copy" Content="Copy" /> <Button Command="ApplicationCommands.Paste" Content="Paste" /> </ToolBar> <ToolBar Band="1"> <TextBlock Text="Font Size" VerticalAlignment="Center" /> <ComboBox Name="cbxFontSize"> <ComboBoxItem Content="12" IsSelected="True" Margin="2" /> <ComboBoxItem Content="14" Margin="2" /> <ComboBoxItem Content="16" Margin="2" /> </ComboBox> <Separator Margin="5"/> <RadioButton Command="EditingCommands.AlignLeft" Content="Left" IsChecked="True"/> <RadioButton Command="EditingCommands.AlignCenter" Content="Center" /> <RadioButton Command="EditingCommands.AlignRight" Content="Right" /> <Separator Margin="5"/> <Button Command="EditingCommands.ToggleBold" Content="Bold" /> <Button Command="EditingCommands.ToggleItalic" Content="Italic" /> <Button Command="EditingCommands.ToggleUnderline" Content="Underline" /> </ToolBar> </ToolBarTray> <RichTextBox Name="rtbTextBox"> <FlowDocument> <Paragraph FontSize="{Binding ElementName=cbxFontSize, Path=SelectedItem.Content}"> this is a test </Paragraph> </FlowDocument> </RichTextBox> </DockPanel> </Window>