How can I change the color of the gridlines of a Grid in WPF?

Question

I have a Grid (not a DataGrid, but a real Grid), with GridLines set to True. How can I change the color of the gridlines? Hardcoded in XAML is ok, since it is just for development-reasons.

<Grid ShowGridLines="True" /> 

Answer 1

Sorry, can't be done with ShowGridLines - you need to style the elements contained.

Exhibit A:

MSDN docs say "Only dotted lines are available because this property is intended as a design tool to debug layout problems and is not intended for use in production quality code. If you want lines inside a Grid, style the elements within the Grid to have borders."

Exhibit B - The WPF Source Code:

Notice the Brushes.Blue and Brushes.Yellow hard-coded in this sealed internal class which System.Windows.Controls.Grid uses to draw the lines.

From Grid.cs

    /// <summary>     /// Helper to render grid lines.      /// </summary>     internal class GridLinesRenderer : DrawingVisual      {          /// <summary>         /// Static initialization          /// </summary>         static GridLinesRenderer()         {             s_oddDashPen = new Pen(Brushes.Blue, c_penWidth);              DoubleCollection oddDashArray = new DoubleCollection();             oddDashArray.Add(c_dashLength);              oddDashArray.Add(c_dashLength);              s_oddDashPen.DashStyle = new DashStyle(oddDashArray, 0);             s_oddDashPen.DashCap = PenLineCap.Flat;              s_oddDashPen.Freeze();              s_evenDashPen = new Pen(Brushes.Yellow, c_penWidth);             DoubleCollection evenDashArray = new DoubleCollection();              evenDashArray.Add(c_dashLength);             evenDashArray.Add(c_dashLength);              s_evenDashPen.DashStyle = new DashStyle(evenDashArray, c_dashLength);              s_evenDashPen.DashCap = PenLineCap.Flat;             s_evenDashPen.Freeze();          } 

Answer 2

var T = Type.GetType("System.Windows.Controls.Grid+GridLinesRenderer," +     " PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35");  var GLR = Activator.CreateInstance(T); GLR.GetType().GetField("s_oddDashPen", BindingFlags.Static | BindingFlags.NonPublic).SetValue(GLR, new Pen(Brushes.Black, 1.0)); GLR.GetType().GetField("s_evenDashPen", BindingFlags.Static | BindingFlags.NonPublic).SetValue(GLR, new Pen(Brushes.Black, 1.0));  myGrid.ShowGridLines = true;