HorizontalAlignment=Stretch, MaxWidth, and Left aligned at the same time?

Question

This seems like it should be easy but I\'m stumped. In WPF, I\'d like a TextBox that stretches to the width of it\'s parent, but only to a maximum width. The problem is that

Answer 1

Functionally similar to the accepted answer, but doesn't require the parent element to be specified:

<TextBox
    Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type FrameworkElement}}}"
    MaxWidth="500"
    HorizontalAlignment="Left" />

Answer 2

In my case I had to put textbox into a stack panel in order to stretch textbox on left side. Thanks to previous post. Just for an example I did set a background color to see what’s happens when window size is changing.

<StackPanel Name="JustContainer" VerticalAlignment="Center" HorizontalAlignment="Stretch" Background="BlueViolet" >
    <TextBox 
       Name="Input" Text="Hello World" 
       MaxWidth="300"
       HorizontalAlignment="Right"
       Width="{Binding ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type FrameworkElement}}}">
    </TextBox>
</StackPanel>