让TextBlock文字变化的动画

<TextBlock>

            <TextBlock.Triggers>

                <EventTrigger RoutedEvent="Loaded">

                    <BeginStoryboard>

                        <Storyboard>

                            <ColorAnimation Storyboard.TargetName="color"

                                            Storyboard.TargetProperty="Color"

                                            From="Red" To="Green" Duration="0:0:0.5"

                                            RepeatBehavior="Forever" AutoReverse="True"/>

                        </Storyboard>

                    </BeginStoryboard>

                </EventTrigger>

            </TextBlock.Triggers>

            one 

            <Run>

                <Run.Foreground>

                    <SolidColorBrush x:Name="color" Color="Red"/>                                                         

                </Run.Foreground>    

                two 

            </Run>            

            three

        </TextBlock>