Let 2 Controls automatic fill space with same size - wpf

Question

I want two texboxes fill the available Space in a panel. But both have to contain the same width. So DockPanel lastchildfill doesn't works here.
I have an image where u can see, i simply created 2 textboxes without any width. The empty Space should be filledby both textboxes like the above (the above is made with manual Width="xxx". But I dont' want to hardcore it like this.
I want it like Grid.Column width="*"
Do I have to create a Grid for each panel? (There will be much more textboxes)
my XAML is simple because I dont know how to realize my idea:
<DockPanel LastChildFill="False">
<TextBox DockPanel.Dock="Left" x:Name="nachname_textbox"/>
<TextBox DockPanel.Dock="Right" x:Name="vorname_textbox"/>
</DockPanel>

Answer 1

UniformGrid control might suit your needs : it automaticaly places all controls in cells with the same amount of width en height for each ones. And you can define how many rows and columns you want.
<UniformGrid Columns=2>
<TextBox />
<TextBox/>
</UniformGrid>

Answer 2

If you want two elements to fill 50% each of the avalable width of a Panel, you should put a Grid with two ColumnDefinitions in each Panel, i.e. simply replace the DockPanel with a Grid:
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<TextBox />
<TextBox Grid.Column="1" />
</Grid>
If you want to decrease the amount of XAML, you could create your own custom Grid class:
public class My2x2Grid : Grid
{
public My2x2Grid()
{
ColumnDefinitions.Add(new ColumnDefinition());
ColumnDefinitions.Add(new ColumnDefinition());
}
}
...and use this one:
<local:My2x2Grid>
<TextBox />
<TextBox Grid.Column="1" />
</Grid>