如何在 C#/WPF 中的网格上设置边框？
这是我想要的，但在整个事物周围设置了一个边框，而不是我在我的应用程序中放置的网格控件。
<Grid>
<Border BorderBrush="Black" BorderThickness="2">
<Grid Height="166" HorizontalAlignment="Left" Margin="12,12,0,0" Name="grid1" VerticalAlignment="Top" Width="479" Background="#FFF2F2F2" />
</Border>
... and so on ...
【问题讨论】：
如果你只想要一个外边框，最简单的方法是把它放在一个Border控件中：
<Border BorderBrush="Black" BorderThickness="2">
<Grid>
<!-- Grid contents here -->
</Grid>
</Border>
您看到边框完全填满控件的原因是，默认情况下，它的 HorizontalAlignment 和 VerticalAlignment 设置为 Stretch。请尝试以下操作：
<Grid>
<Border HorizontalAlignment="Left" VerticalAlignment="Top" BorderBrush="Black" BorderThickness="2">
<Grid Height="166" HorizontalAlignment="Left" Margin="12,12,0,0" Name="grid1" VerticalAlignment="Top" Width="479" Background="#FFF2F2F2" />
</Border>
</Grid>
这应该可以满足您的需求（尽管您可能希望在所有 4 个边上都留出边距，而不仅仅是 2...）
【讨论】：
如果将网格嵌套在边框控件中
<Border>
<Grid>
</Grid>
</Border>
没有做你想做的事，那么你将不得不为网格（或边框）制作你自己的控件模板来做你想做的事。
【讨论】：
我认为你的问题是边距应该在边框标签中指定，而不是在网格中。
【讨论】：
如果将来可能对任何人有用，这是对我有用的稍后答案。我想在网格的所有四个边上都有一个简单的边框，我就这样实现了......
<DataGrid x:Name="dgDisplay" Margin="5" BorderBrush="#1266a7" BorderThickness="1"...
【讨论】：
Grid 控件没有BorderBrush 属性，但DataGrid 有...
<Grid x:Name="outerGrid">
<Grid x:Name="innerGrid">
<Border BorderBrush="#FF179AC8" BorderThickness="2" />
<other stuff></other stuff>
<other stuff></other stuff>
</Grid>
</Grid>
此代码在“innerGrid”内包裹一个边框
【讨论】：
如果有人对类似问题感兴趣，但没有使用 XAML，这是我的解决方案：
var B1 = new Border();
B1.BorderBrush = Brushes.Black;
B1.BorderThickness = new Thickness(0, 1, 0, 0); // You can specify here which borders do you want
YourPanel.Children.Add(B1);
【讨论】：
这是我的解决方案，希望对你有用：
public class Sheet : Grid
{
public static readonly DependencyProperty BorderBrushProperty = DependencyProperty.Register(nameof(BorderBrush), typeof(Brush), typeof(Sheet), new FrameworkPropertyMetadata(Brushes.Transparent, FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender, OnBorderBrushChanged));
public static readonly DependencyProperty BorderThicknessProperty = DependencyProperty.Register(nameof(BorderThickness), typeof(double), typeof(Sheet), new FrameworkPropertyMetadata(1D, FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender, OnBorderThicknessChanged, CoerceBorderThickness));
public static readonly DependencyProperty CellSpacingProperty = DependencyProperty.Register(nameof(CellSpacing), typeof(double), typeof(Sheet), new FrameworkPropertyMetadata(0D, FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender, OnCellSpacingChanged, CoerceCellSpacing));
public Brush BorderBrush
{
get => this.GetValue(BorderBrushProperty) as Brush;
set => this.SetValue(BorderBrushProperty, value);
}
public double BorderThickness
{
get => (double)this.GetValue(BorderThicknessProperty);
set => this.SetValue(BorderThicknessProperty, value);
}
public double CellSpacing
{
get => (double)this.GetValue(CellSpacingProperty);
set => this.SetValue(CellSpacingProperty, value);
}
protected override Size ArrangeOverride(Size arrangeSize)
{
Size size = base.ArrangeOverride(arrangeSize);
double border = this.BorderThickness;
double doubleBorder = border * 2D;
double spacing = this.CellSpacing;
double halfSpacing = spacing * 0.5D;
if (border > 0D || spacing > 0D)
{
foreach (UIElement child in this.InternalChildren)
{
this.GetChildBounds(child, out double left, out double top, out double width, out double height);
left += halfSpacing + border;
top += halfSpacing + border;
height -= spacing + doubleBorder;
width -= spacing + doubleBorder;
if (width < 0D)
{
width = 0D;
}
if (height < 0D)
{
height = 0D;
}
left -= left % 0.5D;
top -= top % 0.5D;
width -= width % 0.5D;
height -= height % 0.5D;
child.Arrange(new Rect(left, top, width, height));
}
if (border > 0D && this.BorderBrush != null)
{
this.InvalidateVisual();
}
}
return size;
}
protected override void OnRender(DrawingContext dc)
{
base.OnRender(dc);
if (this.BorderThickness > 0D && this.BorderBrush != null)
{
if (this.CellSpacing == 0D)
{
this.DrawCollapsedBorder(dc);
}
else
{
this.DrawSeperatedBorder(dc);
}
}
}
private void DrawSeperatedBorder(DrawingContext dc)
{
double spacing = this.CellSpacing;
double halfSpacing = spacing * 0.5D;
#region draw border
Pen pen = new Pen(this.BorderBrush, this.BorderThickness);
UIElementCollection children = this.InternalChildren;
foreach (UIElement child in children)
{
this.GetChildBounds(child, out double left, out double top, out double width, out double height);
left += halfSpacing;
top += halfSpacing;
width -= spacing;
height -= spacing;
dc.DrawRectangle(null, pen, new Rect(left, top, width, height));
}
#endregion
}
private void DrawCollapsedBorder(DrawingContext dc)
{
RowDefinitionCollection rows = this.RowDefinitions;
ColumnDefinitionCollection columns = this.ColumnDefinitions;
int rowCount = rows.Count;
int columnCount = columns.Count;
const byte BORDER_LEFT = 0x08;
const byte BORDER_TOP = 0x04;
const byte BORDER_RIGHT = 0x02;
const byte BORDER_BOTTOM = 0x01;
byte[,] borderState = new byte[rowCount, columnCount];
int column = columnCount - 1;
int columnSpan;
int row = rowCount - 1;
int rowSpan;
#region generate main border data
for (int i = 0; i < rowCount; i++)
{
borderState[i, 0] = BORDER_LEFT;
borderState[i, column] = BORDER_RIGHT;
}
for (int i = 0; i < columnCount; i++)
{
borderState[0, i] |= BORDER_TOP;
borderState[row, i] |= BORDER_BOTTOM;
}
#endregion
#region generate child border data
UIElementCollection children = this.InternalChildren;
foreach (UIElement child in children)
{
this.GetChildLayout(child, out row, out rowSpan, out column, out columnSpan);
for (int i = 0; i < rowSpan; i++)
{
borderState[row + i, column] |= BORDER_LEFT;
borderState[row + i, column + columnSpan - 1] |= BORDER_RIGHT;
}
for (int i = 0; i < columnSpan; i++)
{
borderState[row, column + i] |= BORDER_TOP;
borderState[row + rowSpan - 1, column + i] |= BORDER_BOTTOM;
}
}
#endregion
#region draw border
Pen pen = new Pen(this.BorderBrush, this.BorderThickness);
double left;
double top;
double width, height;
for (int r = 0; r < rowCount; r++)
{
RowDefinition v = rows[r];
top = v.Offset;
height = v.ActualHeight;
for (int c = 0; c < columnCount; c++)
{
byte state = borderState[r, c];
ColumnDefinition h = columns[c];
left = h.Offset;
width = h.ActualWidth;
if ((state & BORDER_LEFT) == BORDER_LEFT)
{
dc.DrawLine(pen, new Point(left, top), new Point(left, top + height));
}
if ((state & BORDER_TOP) == BORDER_TOP)
{
dc.DrawLine(pen, new Point(left, top), new Point(left + width, top));
}
if ((state & BORDER_RIGHT) == BORDER_RIGHT && (c + 1 >= columnCount || (borderState[r, c + 1] & BORDER_LEFT) == 0))
{
dc.DrawLine(pen, new Point(left + width, top), new Point(left + width, top + height));
}
if ((state & BORDER_BOTTOM) == BORDER_BOTTOM && (r + 1 >= rowCount || (borderState[r + 1, c] & BORDER_TOP) == 0))
{
dc.DrawLine(pen, new Point(left, top + height), new Point(left + width, top + height));
}
}
}
#endregion
}
private void GetChildBounds(UIElement child, out double left, out double top, out double width, out double height)
{
ColumnDefinitionCollection columns = this.ColumnDefinitions;
RowDefinitionCollection rows = this.RowDefinitions;
int rowCount = rows.Count;
int row = (int)child.GetValue(Grid.RowProperty);
if (row >= rowCount)
{
row = rowCount - 1;
}
int rowSpan = (int)child.GetValue(Grid.RowSpanProperty);
if (row + rowSpan > rowCount)
{
rowSpan = rowCount - row;
}
int columnCount = columns.Count;
int column = (int)child.GetValue(Grid.ColumnProperty);
if (column >= columnCount)
{
column = columnCount - 1;
}
int columnSpan = (int)child.GetValue(Grid.ColumnSpanProperty);
if (column + columnSpan > columnCount)
{
columnSpan = columnCount - column;
}
left = columns[column].Offset;
top = rows[row].Offset;
ColumnDefinition right = columns[column + columnSpan - 1];
width = right.Offset + right.ActualWidth - left;
RowDefinition bottom = rows[row + rowSpan - 1];
height = bottom.Offset + bottom.ActualHeight - top;
if (width < 0D)
{
width = 0D;
}
if (height < 0D)
{
height = 0D;
}
}
private void GetChildLayout(UIElement child, out int row, out int rowSpan, out int column, out int columnSpan)
{
int rowCount = this.RowDefinitions.Count;
row = (int)child.GetValue(Grid.RowProperty);
if (row >= rowCount)
{
row = rowCount - 1;
}
rowSpan = (int)child.GetValue(Grid.RowSpanProperty);
if (row + rowSpan > rowCount)
{
rowSpan = rowCount - row;
}
int columnCount = this.ColumnDefinitions.Count;
column = (int)child.GetValue(Grid.ColumnProperty);
if (column >= columnCount)
{
column = columnCount - 1;
}
columnSpan = (int)child.GetValue(Grid.ColumnSpanProperty);
if (column + columnSpan > columnCount)
{
columnSpan = columnCount - column;
}
}
private static void OnBorderBrushChanged(DependencyObject d, DependencyPropertyChangedEventArgs args)
{
if (d is UIElement element)
{
element.InvalidateVisual();
}
}
private static void OnBorderThicknessChanged(DependencyObject d, DependencyPropertyChangedEventArgs args)
{
if (d is UIElement element)
{
element.InvalidateArrange();
}
}
private static void OnCellSpacingChanged(DependencyObject d, DependencyPropertyChangedEventArgs args)
{
if (d is UIElement element)
{
element.InvalidateArrange();
}
}
private static object CoerceBorderThickness(DependencyObject d, object baseValue)
{
if (baseValue is double value)
{
return value < 0D || double.IsNaN(value) || double.IsInfinity(value) ? 0D : value;
}
return 0D;
}
private static object CoerceCellSpacing(DependencyObject d, object baseValue)
{
if (baseValue is double value)
{
return value < 0D || double.IsNaN(value) || double.IsInfinity(value) ? 0D : value;
}
return 0D;
}
}
【讨论】：