下面的 XAML 中 * (星号)的含义是什么?
<ColumnDefinition Width="0.07*"/>
<Grid Height="100" HorizontalAlignment="Left"
Margin="102,134,0,0"
Name="grid1" VerticalAlignment="Top"
Width="354">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="40*" />
<ColumnDefinition Width="314*" />
</Grid.ColumnDefinitions>
</Grid>