下面以代码示例
1.
<DockPanel LastChildFill="True">
<Button DockPanel.Dock="Top">Top</Button>
<Button DockPanel.Dock="Bottom">Bottom</Button>
<Button DockPanel.Dock="Left">Left</Button>
<Button DockPanel.Dock="Right">Right</Button>
<Button>Fill</Button>
</DockPanel>


2.调整顺序后的变化
<DockPanel LastChildFill="True">
<Button DockPanel.Dock="Left">Left</Button>
<Button DockPanel.Dock="Right">Right</Button>
<Button DockPanel.Dock="Top">Top</Button>
<Button DockPanel.Dock="Bottom">Bottom</Button>
<Button>Fill</Button>
</DockPanel>

3.当LastChildFill属性为Flase时的变化
<DockPanel LastChildFill="False">
<Button DockPanel.Dock="Left">Left</Button>
<Button DockPanel.Dock="Right">Right</Button>
<Button DockPanel.Dock="Top">Top</Button>
<Button DockPanel.Dock="Bottom">Bottom</Button>
<Button>Fill</Button>
</DockPanel>
结束