如何以编程方式保持wpf中对象的纵横比

Question

我以编程方式将具有特定宽度和高度的Border 添加到网格中。但是，我想获得以下任何一项：

1. 使边框保持纵横比和填充使其在网格内尽可能大
2. 每当网格缩小或放大时使边框缩放（所以不是特别大，更像是网格的百分比）

目前这是我调整窗口大小时的情况：

Color borderColor = (Color)ColorConverter.ConvertFromString(BorderColor);
Color backgroundColor = (Color)ColorConverter.ConvertFromString(BackgroundColor);

Border border = new Border();
border.BorderThickness = new Thickness(BorderSize);
border.CornerRadius = new CornerRadius(TopLeftCornerRadius, TopRightCornerRadius, BottomRightCornerRadius, BottomLeftCornerRadius);
border.BorderBrush = (SolidColorBrush)(new BrushConverter().ConvertFrom(BorderColor));
border.Background = (SolidColorBrush)(new BrushConverter().ConvertFrom(BackgroundColor));

border.Width = Width;
border.Height = Height;

border.Margin = new Thickness(10);

previewgrid.Children.Add(border);

正常情况：

规模化情况：

所以我希望它能够正确调整大小并保持在白色矩形内。顺便说一句，如您所见，白色网格有一个边距；-) 提前致谢！

Answer 1

正如 lerthe61 建议的那样，只需使用 Viewbox 并将其 Stretch 属性设置为 Uniform：

Color borderColor = (Color)ColorConverter.ConvertFromString(BorderColor);
Color backgroundColor = (Color)ColorConverter.ConvertFromString(BackgroundColor);

Border border = new Border();
border.BorderThickness = new Thickness(BorderSize);
border.CornerRadius = new CornerRadius(TopLeftCornerRadius, TopRightCornerRadius, BottomRightCornerRadius, BottomLeftCornerRadius);
border.BorderBrush = (SolidColorBrush)(new BrushConverter().ConvertFrom(BorderColor));
border.Background = (SolidColorBrush)(new BrushConverter().ConvertFrom(BackgroundColor));

border.Width = Width;
border.Height = Height;

border.Margin = new Thickness(10);

Viewbox viewBox = new Viewbox();
viewBox.Stretch = Stretch.Uniform;
viewBox.Child = border;

previewgrid.Children.Add(viewBox);

请注意，如果previewgrid 是Canvas，则此解决方案不起作用。 希望对你有帮助。

Answer 2

最简单的方法：

 <Grid Margin="50">
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="50" />
        <ColumnDefinition Width="*" />
        <ColumnDefinition Width="50" />
    </Grid.ColumnDefinitions>
    <Border CornerRadius="50,0,0,50"
            Background="Green" />
    <Border CornerRadius="0"
            Grid.Column="1"
            Background="Green" />
    <Border CornerRadius="0,50,50,0"
            Grid.Column="2"
            Background="Green" />

</Grid>

通过 C#：

        myGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(50) });
        myGrid.ColumnDefinitions.Add(new ColumnDefinition());
        myGrid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(50) });

        Border b1 = new Border
        {
            Background = new SolidColorBrush(Colors.Blue),
            CornerRadius = new CornerRadius(100, 0, 0, 100)
        };

        Grid.SetColumn(b1, 0);

        Border b2 = new Border
        {
            Background = new SolidColorBrush(Colors.Blue),
        };
        Grid.SetColumn(b2, 1);
        Border b3 = new Border
        {
            Background = new SolidColorBrush(Colors.Blue),
            CornerRadius = new CornerRadius(0, 100, 100, 0),
        };
        Grid.SetColumn(b3, 2);

        myGrid.Children.Add(b1);
        myGrid.Children.Add(b2);
        myGrid.Children.Add(b3);

正常：

调整大小：

对你来说够好吗？