<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition />
        <ColumnDefinition Width="Auto" />
    </Grid.ColumnDefinitions>
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto" />
        <RowDefinition Height="Auto" />
    </Grid.RowDefinitions>

    <TextBlock Grid.Row="0"
               Grid.Column="0"
               Grid.ColumnSpan="2"
               Text="选择目录：" />

    <TextBox Grid.Row="1"
             Grid.Column="0"
             Text="D:\Test" />
    <Button Grid.Row="1"
            Grid.Column="1"
            Width="60"
            Height="24"
            Content="浏览...." />
</Grid>