WPF Grid自动画边框线，找到一个很好的控件GridOption，顺便修复这个控件的一个bug

GridOption可以自动的帮我们画出Grid边框线，并且支持Grid.RowSpan, ColumnSpan。

代码如下：

注意红线处的代码，修复了来回切换界面时，边框线越来越粗的问题，同时也需要注意，修改边框线属性，要重启才能生效

public class GridOption
{
    //暂时不处理实时显示的事情
    #region 显示边框信息
    public static readonly DependencyProperty ShowBorderProperty =
        DependencyProperty.RegisterAttached("ShowBorder", typeof(bool), typeof(GridOption)
            , new PropertyMetadata(OnShowBorderChanged));
    public static bool GetShowBorder(DependencyObject obj)
    {
        return (bool)obj.GetValue(ShowBorderProperty);
    }

    public static void SetShowBorder(DependencyObject obj, bool value)
    {
        obj.SetValue(ShowBorderProperty, value);
    }

    public static void OnShowBorderChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var grid = d as Grid;
        if ((bool)e.OldValue)
            grid.Loaded -= (s, arg) => { };
        else
        {
            grid.Loaded += new RoutedEventHandler(GridLoaded);
        }
    }
    #endregion
    #region 线宽信息
    public static readonly DependencyProperty LineThicknessProperty =
       DependencyProperty.RegisterAttached("LineThickness", typeof(double), typeof(GridOption),
           new PropertyMetadata(1d, OnGridLineThicknessChanged));
    public static double GetLineThickness(DependencyObject obj)
    {
        return (double)obj.GetValue(LineThicknessProperty);
    }

    public static void SetLineThickness(DependencyObject obj, double value)
    {
        obj.SetValue(LineThicknessProperty, value);
    }


    public static void OnGridLineThicknessChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {

    }
    #endregion

    public static readonly DependencyProperty LineBrushProperty =
        DependencyProperty.RegisterAttached("LineBrush", typeof(Brush), typeof(GridOption),
            new PropertyMetadata(Brushes.Gray, OnGridLineBrushChanged));

    #region 线画刷问题
    public static Brush GetLineBrush(DependencyObject obj)
    {
        var brush = (Brush)obj.GetValue(LineBrushProperty);
        return brush ?? Brushes.LightGray;
    }

    public static void SetLineBrush(DependencyObject obj, Brush value)
    {
        obj.SetValue(LineBrushProperty, value);
    }

    public static void OnGridLineBrushChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {

    }
    #endregion

    private static void GridLoaded(object sender, RoutedEventArgs e)
    {
        #region 思路
        /*
         * 1、覆盖所有单元格都要包围上边框。
         * 2、边框线不能存在重复。每个单元格绘制【右下】部分，主体绘制右上部分
         */
        #endregion
        var grid = sender as Grid;
        var rowCount = Math.Max(1, grid.RowDefinitions.Count);
        var columnCount = Math.Max(1, grid.ColumnDefinitions.Count);
        #region 初始化标准数组
        int[,] flagArray = new int[rowCount, columnCount];
        #endregion
        var controls = grid.Children;
        var count = controls.Count;
        var settingThickness = GetLineThickness(grid);
        var borderBrush = GetLineBrush(grid);
        
        for (int i = 0; i < count; i++)
        {
            var item = controls[i] as FrameworkElement;
            var row = Grid.GetRow((item));
            var column = Grid.GetColumn(item);
            var rowSpan = Grid.GetRowSpan(item);
            var columnSpan = Grid.GetColumnSpan(item);
            for (int rowTemp = 0; rowTemp < rowSpan; rowTemp++)
            {
                for (int colTemp = 0; colTemp < columnSpan; colTemp++)
                {
                    flagArray[rowTemp + row, colTemp + column] = 1;
                }
            }

            var border = CreateBorder(row, column, rowSpan, columnSpan, settingThickness);
            border.BorderBrush = borderBrush;

            grid.Children.RemoveAt(i);
            border.Child = item;
            grid.Children.Insert(i, border);
        }

        #region 整理为填充单元格
        for (int i = 0; i < rowCount; i++)
        {
            for (int k = 0; k < columnCount; k++)
            {
                if (flagArray[i, k] == 0)
                {
                    var border = CreateBorder(i, k, 1, 1, settingThickness);
                    border.BorderBrush = borderBrush;
                    grid.Children.Add(border);
                }
            }
        }
        #endregion

        grid.Loaded -= GridLoaded;//这一句很重要，修复了来回切换界面时，边框线越来越粗的问题，同时也需要注意，修改边框线属性，要重启才能生效

    }

    private static Border CreateBorder(int row, int column, int rowSpan, int columnSpan, double thickness)
    {
        var useThickness = new Thickness(0, 0, thickness, thickness);
        if (row == 0)
            useThickness.Top = thickness;
        if (column == 0)
            useThickness.Left = thickness;
        var border = new Border()
        {
            BorderThickness = useThickness,
        };
        Grid.SetRow(border, row);
        Grid.SetColumn(border, column);
        Grid.SetRowSpan(border, rowSpan);
        Grid.SetColumnSpan(border, columnSpan);
        return border;
    }
}