Matching grid and window size WPF - wpf

Question

I just started using WPF (instead of winforms) and I'm trying to create a fixed-sized window (see image).
Problem is, whenever I run the app the bottom right corner gets messed up, having near zero space between the button and the edge. (see other image)
Here's the XAML code (mostly generated by the Visual Studio designer)
<Window x:Class="UseCaseHelper.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:UseCaseHelper"
mc:Ignorable="d"
Title="UseCaseHelper" Height="500" Width="900">
<Grid>
<Button x:Name="button" Content="Button" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="75"/>
<Button x:Name="button1" Content="Button" HorizontalAlignment="Left" Margin="809,441,0,0" VerticalAlignment="Top" Width="75"/>
</Grid>
</Window>
I've tried googling for a solution without much success. Hopefully someone can point out what I'm doing wrong here.

Answer 1

I always find DockPanel more flexible in these settings. Instead of the VerticalAlighnment and the Margin you set, you can set DockPanel.Dock to Left, Right, Bottom or Top.
<DockPanel LastChildFill="False">
<Button DockPanel.Dock="Top"
Content="Button" HorizontalAlignment="Left" Margin="10,10,0,0"
Width="75"/>
<Button DockPanel.Dock="Bottom"
Content="Button" HorizontalAlignment="Right" Margin="0,0,10,10" Width="75"/>
</DockPanel>
Note that you can also use Margin="10" for both Buttons.
However, if you want to use Grid, you can use the following structure:
<Grid>
<Button Content="Button" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="10,10,0,0"
Width="75"/>
<Button Content="Button" HorizontalAlignment="Right" VerticalAlignment="Bottom" Margin="0,0,10,10" Width="75"/>
</Grid>
Note that in this case they will overlap if the Window is small enough.
Another option is to add RowDefinitions and ColumnDefinitions to the Grid:
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Button
Content="Button" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="10,10,0,0"
Width="75"/>
<Button Grid.Column="2" Grid.Row="2"
Content="Button" HorizontalAlignment="Right" VerticalAlignment="Bottom" Margin="0,0,10,10" Width="75"/>
</Grid>
Its perfomance is better than the other two, if Window is very small.