How do you implement default text for a search box in WPF?

Question

I want to implement something exactly like "Changing the Default Text in the Search Box" for a WPF search TextBox. The box should show some greyed out "Search.." text when it's empty, and then it should function normally when text is typed in. The linked article shows how to do this in javascript. How would one start down this path in WPF? The best idea I've had so far is another text box on top of the main one that goes invisible whenever the search textbox gets focus or text.

Answer 1

This style will show text using a the background property and a visualbrush. Once control gets focus the text is removed.

    <TextBox.Style>
            <Style TargetType="TextBox">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Path=Text}" Value="">
                        <Setter Property="Background">
                            <Setter.Value>
                                <VisualBrush Stretch="None">
                                    <VisualBrush.Visual>
                                        <TextBlock Text="Enter value" Foreground="Gray"/>
                                    </VisualBrush.Visual>
                                </VisualBrush>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Path=Text}" Value="{x:Null}">
                        <Setter Property="Background">
                            <Setter.Value>
                                <VisualBrush Stretch="None">
                                    <VisualBrush.Visual>
                                        <TextBlock Text="Enter value" Foreground="Gray"/>
                                    </VisualBrush.Visual>
                                </VisualBrush>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Path=IsFocused}" Value="True">
                        <Setter Property="Background">
                            <Setter.Value>
                                <VisualBrush Stretch="None">
                                </VisualBrush>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                </Style.Triggers>
            </Style>
        </TextBox.Style>

Answer 2

Try the InfoTextBox sample from Kevin Moore's Bag-o-Tricks. You can download it from http://work.j832.com/2008/01/real-update-to-bag-o-tricks.html