TreeView DrawNode Event Problem

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C#

C#4.0

Hi,

I have a TreeView in one form. I have used the DrawNode event to create two columns in the TreeView. Source code, which is taken from microsoft msdn site, used is given below:

private void tvwCOA_DrawNode(object sender, DrawTreeNodeEventArgs e)
{
  int intFlag = 0;

  // Draw the background and node text for a selected node.
  if ((e.State & TreeNodeStates.Selected) != 0)
  {
    // 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, e.Bounds.X, e.Bounds.Y);
    e.Graphics.DrawString(clsCommon.Right(e.Node.Tag.ToString(), 8), nodeFont, Brushes.White, 435, e.Bounds.Y);
                intFlag = 1;
  }

  // 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 (intFlag != 1)
  {
    e.Graphics.DrawString(clsCommon.Right(e.Node.Tag.ToString(), 8), tagFont, Brushes.Black, 435, 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) != 0)
  {
    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 - 1,
      focusBounds.Height - 1);
      e.Graphics.DrawRectangle(focusPen, focusBounds);
    }
  }
} 

private Rectangle NodeBounds(TreeNode node)
{
  // Set the return value to the normal node bounds.
  Rectangle bounds = node.Bounds;
  if (node.Tag != null)
  {
    // Retrieve a Graphics object from the TreeView handle
    // and use it to calculate the display width of the tag.
    Graphics g = tvwCOA.CreateGraphics();
    //int tagWidth = (int)g.MeasureString (node.Tag.ToString(), tagFont).Width + 6;
    int tagWidth = 485; // (int)g.MeasureString(node.Text.ToString(), tagFont).Width + 6;
    // Adjust the node bounds using the calculated value.
    bounds.Offset(tagWidth / 2, 0);
    bounds = Rectangle.Inflate(bounds, tagWidth / 2, 0);
    g.Dispose();
  }

  return bounds;
}

Each node has a value in the tag. The problem I am facing is whenever I click a node to expand it, the tag value of the first node in the TreeView ( which is printed against the first node at X= 435 ) is overwritten by the tag value of the first child of the expanded node. If we scroll down and come to the first node the value is correct. I tried a lot but could not locate where I am making a mistake. Hope I explained well. Please help.

Cris Evan