滚动条滑到底完美解决方案（适合任何带滚动条或ScrollBar控件 - c++编程基础

if (Scroll != null)
{
ScrollView = Scroll;
ScrollView.ValueChanged += ScrollView_ValueChanged;
}
}

void ScrollView_ValueChanged(object sender, RoutedPropertyChangedEventArgs e)
{
OnOffsetChanged();
}

void OnOffsetChanged()
{
if (ScrollView == null)
return;

ScrollBar Scroll = ScrollView;

switch (DirectionType)
{
case DirectionType.Top:
case DirectionType.Left:
{
if (Scroll.Maximum < double.Epsilon || Scroll.Value - Scroll.ViewportSize > 0)
return;
}
break;
case DirectionType.Bottom:
case DirectionType.Right:
{
if (Scroll.Maximum < double.Epsilon || Scroll.Value + Scroll.ViewportSize < Scroll.Maximum)
return;
}
break;
default: break;
}

if (ScrollTrigger != null)
{
ScrollTrigger(this.AssociatedObject,new EventArgs());
}
base.InvokeActions(null);

}
}

public enum DirectionType { Top, Bottom, Left, Right }
public class ScrollBarTrigger : TriggerBase
{
ScrollBar ScrollView;
public static readonly DependencyProperty DirectionTypeProperty = DependencyProperty.Register("DirectionType", typeof(DirectionType), typeof(ScrollBarTrigger), new PropertyMetadata(DirectionType.Bottom));

public DirectionType DirectionType
{
get
{
return (DirectionType)base.GetValue(ScrollBarTrigger.DirectionTypeProperty);
}
set
{
base.SetValue(ScrollBarTrigger.DirectionTypeProperty, value);
}

}

public event EventHandler ScrollTrigger;

protected override void OnAttached()
{
base.OnAttached();

if (this.AssociatedObject != null && this.AssociatedObject is FrameworkElement)
{
(this.AssociatedObject as FrameworkElement).SizeChanged += control_SizeChanged;
}
}

protected override void OnDetaching()
{
base.OnDetaching();

if (ScrollView != null)
ScrollView.ValueChanged -= ScrollView_ValueChanged;

if (this.AssociatedObject != null && this.AssociatedObject is FrameworkElement)
{
(this.AssociatedObject as FrameworkElement).SizeChanged -= control_SizeChanged;
}
}

void control_SizeChanged(object sender, SizeChangedEventArgs e)
{
if (this.AssociatedObject == null || !(this.AssociatedObject is FrameworkElement))
return;

ScrollBar Scroll = this.AssociatedObject.GetFirstDescendantOfType();
if (Scroll != null)
{
AttachedScroll(Scroll);
(this.AssociatedObject as FrameworkElement).SizeChanged -= control_SizeChanged;
}
}

void AttachedScroll(ScrollBar Scroll)
{
if (Scroll != null)

滚动条滑到底完美解决方案（适合任何带滚动条或ScrollBar控件 (六)