WinForm TreeView节点重绘，失去焦点的高亮显示

当用户焦点离开TreeView时，TreeView选中节点仍然高亮，但是颜色符合主题。

设置TreeView.HideSelection = False;可让选中节点保持高亮。

添加重绘事件

TreeView.DrawMode = TreeViewDrawMode.OwnerDrawText;

TreeView.DrawNode += new DrawTreeNodeEventHandler(TreeView_DrawNode);

// Draws a node.
 private void TreeView_DrawNode(object sender, DrawTreeNodeEventArgs e)
{
     // Draw the background and node text for a selected node.
   if ((e.State & TreeNodeStates.Selected) != )
   {
       // Draw the background of the selected node. The NodeBounds
       // method makes the highlight rectangle large enough to
       // include the text of a node tag, if one is present.
       e.Graphics.FillRectangle(Brushes.Green, NodeBounds(e.Node));
      // Retrieve the node font. If the node font has not been set,
      // use the TreeView font.
      Font nodeFont = e.Node.NodeFont;
     if (nodeFont == null)
       nodeFont = ((TreeView)sender).Font;
     // Draw the node text.
      e.Graphics.DrawString(e.Node.Text, nodeFont, Brushes.White,
      Rectangle.Inflate(e.Bounds, , ));
   }
      // Use the default background and node text.
  else
   {
      e.DrawDefault = true;
   }
   // If a node tag is present, draw its string representation
   // to the right of the label text.
  if (e.Node.Tag != null)
  {
     e.Graphics.DrawString(e.Node.Tag.ToString(), tagFont, Brushes.Yellow, e.Bounds.Right + , e.Bounds.Top);
  }
  // If the node has focus, draw the focus rectangle large, making
  // it large enough to include the text of the node tag, if present.
 if ((e.State & TreeNodeStates.Focused) != )
 {
   using (Pen focusPen = new Pen(Color.Black))
    {
      focusPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dot;
      Rectangle focusBounds = NodeBounds(e.Node);
      focusBounds.Size = new Size(focusBounds.Width - , focusBounds.Height - );
      e.Graphics.DrawRectangle(focusPen, focusBounds);
    }
  }
}