<Window x:Class="Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="UseProgressBar" Height="140" Width="300"> <Grid> <ProgressBar Height="21" Name="prgTime" VerticalAlignment="Bottom" /> <Button Height="23" Margin="100,16,100,0" Name="btnStart" VerticalAlignment="Top" Content="Start"> <Button.Triggers> <EventTrigger RoutedEvent="Button.Click"> <EventTrigger.Actions> <BeginStoryboard> <Storyboard Duration="5"> <DoubleAnimation Storyboard.TargetName="prgTime" Storyboard.TargetProperty="Value" Duration="0:0:5" From="0" To="100" /> <DoubleAnimation Storyboard.TargetName="prgTime" Storyboard.TargetProperty="Value" BeginTime="0:0:6" Duration="0:0:0" From="100" To="0" /> </Storyboard> </BeginStoryboard> </EventTrigger.Actions> </EventTrigger> </Button.Triggers> </Button> </Grid> </Window>