也许我仍然可以帮助遇到这个问题的人,因为这是一个非常老的问题。
我也需要这个,并写了一个行为来解决这个问题。所以这是行为:
public class StretchMaxWidthBehavior : Behavior<FrameworkElement>
{
protected override void OnAttached()
{
base.OnAttached();
((FrameworkElement)this.AssociatedObject.Parent).SizeChanged += this.OnSizeChanged;
}
protected override void OnDetaching()
{
base.OnDetaching();
((FrameworkElement)this.AssociatedObject.Parent).SizeChanged -= this.OnSizeChanged;
}
private void OnSizeChanged(object sender, SizeChangedEventArgs e)
{
this.SetAlignments();
}
private void SetAlignments()
{
var slot = LayoutInformation.GetLayoutSlot(this.AssociatedObject);
var newWidth = slot.Width;
var newHeight = slot.Height;
if (!double.IsInfinity(this.AssociatedObject.MaxWidth))
{
if (this.AssociatedObject.MaxWidth < newWidth)
{
this.AssociatedObject.HorizontalAlignment = HorizontalAlignment.Left;
this.AssociatedObject.Width = this.AssociatedObject.MaxWidth;
}
else
{
this.AssociatedObject.HorizontalAlignment = HorizontalAlignment.Stretch;
this.AssociatedObject.Width = double.NaN;
}
}
if (!double.IsInfinity(this.AssociatedObject.MaxHeight))
{
if (this.AssociatedObject.MaxHeight < newHeight)
{
this.AssociatedObject.VerticalAlignment = VerticalAlignment.Top;
this.AssociatedObject.Height = this.AssociatedObject.MaxHeight;
}
else
{
this.AssociatedObject.VerticalAlignment = VerticalAlignment.Stretch;
this.AssociatedObject.Height = double.NaN;
}
}
}
}
然后,您可以像这样使用它:
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="0" Text="Label" />
<TextBox Grid.Column="1" MaxWidth="600">
<i:Interaction.Behaviors>
<cbh:StretchMaxWidthBehavior/>
</i:Interaction.Behaviors>
</TextBox>
</Grid>
最后忘了使用System.Windows.Interactivity
命名空间来使用行为。