示例
此示例演示如何处理 ScrollViewer 的 ScrollChanged 事件。
在 XAML 中定义了具有 Paragraph 部件的 FlowDocument 元素。 当由于用户交互而发生 ScrollChanged 事件时，将调用一个处理程序，且会向 TextBlock 中写入文本，指示发生了该事件。
<ScrollViewer Name="sv1" CanContentScroll="False" ScrollChanged="sChanged">
<FlowDocument FontFamily="Arial" PageWidth="400">
<Paragraph>
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
</Paragraph>
...
<Paragraph>
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
</Paragraph>
</FlowDocument>
</ScrollViewer>
Private Sub sChanged(ByVal sender As Object, ByVal args As ScrollChangedEventArgs)
If (sv1.CanContentScroll = True) Then
tBlock1.Foreground = System.Windows.Media.Brushes.Red
tBlock1.Text = "ScrollChangedEvent just Occurred"
tBlock3.Text = "ExtentWidth is now " + args.ExtentWidth.ToString()
tBlock4.Text = "ExtentHeightChange was " + args.ExtentHeightChange.ToString()
tBlock5.Text = "ExtentWidthChange was " + args.ExtentWidthChange.ToString()
tBlock6.Text = "HorizontalOffset is now " + args.HorizontalOffset.ToString()
tBlock7.Text = "VerticalOffset is now " + args.VerticalOffset.ToString()
tBlock8.Text = "HorizontalChange was " + args.HorizontalChange.ToString()
tBlock9.Text = "VerticalChange was " + args.VerticalChange.ToString()
tBlock10.Text = "ViewportHeight is now " + args.ViewportHeight.ToString()
tBlock11.Text = "ViewportWidth is now " + args.ViewportWidth.ToString()
tBlock12.Text = "ViewportHeightChange was " + args.ViewportHeightChange.ToString()
tBlock13.Text = "ViewportWidthChange was " + args.ViewportWidthChange.ToString()
Else
tBlock1.Text = ""
End If
private void sChanged(object sender, ScrollChangedEventArgs e)
{
if (sv1.CanContentScroll == true)
{
tBlock1.Foreground = System.Windows.Media.Brushes.Red;
tBlock1.Text = "ScrollChangedEvent just Occurred";
tBlock2.Text = "ExtentHeight is now " + e.ExtentHeight.ToString();
tBlock3.Text = "ExtentWidth is now " + e.ExtentWidth.ToString();
tBlock4.Text = "ExtentHeightChange was " + e.ExtentHeightChange.ToString();
tBlock5.Text = "ExtentWidthChange was " + e.ExtentWidthChange.ToString();
tBlock6.Text = "HorizontalOffset is now " + e.HorizontalOffset.ToString();
tBlock7.Text = "VerticalOffset is now " + e.VerticalOffset.ToString();
tBlock8.Text = "HorizontalChange was " + e.HorizontalChange.ToString();
tBlock9.Text = "VerticalChange was " + e.VerticalChange.ToString();
tBlock10.Text = "ViewportHeight is now " + e.ViewportHeight.ToString();
tBlock11.Text = "ViewportWidth is now " + e.ViewportWidth.ToString();
tBlock12.Text = "ViewportHeightChange was " + e.ViewportHeightChange.ToString();
tBlock13.Text = "ViewportWidthChange was " + e.ViewportWidthChange.ToString();
}
else
{
tBlock1.Text = "";
}