Usercontrol自动调整边框

Question

我正在Controls中创建一组UserControl。但是第二个UserControl的边界也会围绕第一个绘制的UserControl绘制。 这里有一段视频来说明我的意思：https://vid.me/e/rZ3N如何才能使边框仅围绕UserControl本身绘制？

这是我将UserControl添加到

的Controls类

public class GroupUserControl : UserControl
{
    private Point mDown { get; set; }
    private Point conLoc { get; set; }

    public GroupUserControl()
    {
        AutoSize = true;
        BorderStyle = BorderStyle.FixedSingle;
    }

    protected override void OnMouseDown(MouseEventArgs e)
    {
        base.OnMouseDown(e);
        mDown = e.Location;
        conLoc = this.Location;
    }


    protected override void OnMouseMove(MouseEventArgs e)
    {
        // Call MyBase.OnMouseMove to activate the delegate. 
        base.OnMouseMove(e);


        if (e.Button == MouseButtons.Left)
        {
            Location = new Point(e.X + Left - mDown.X, e.Y + Top - mDown.Y);
        }
    }


}

TreeView拖放方法

    private void shapeTreeView_DragDrop(object sender, DragEventArgs e)
    {
        if (e.Data.GetDataPresent("System.Windows.Forms.TreeNode", true))
        {
            // node exists in drag data payload
            Point pt = this.shapeTreeView.PointToClient(new Point(e.X, e.Y));


            // Get a handle to the destination node. This will become the parent of our new node.
            TreeNode DestinationNode = this.shapeTreeView.GetNodeAt(pt);

            // Create the new node based on the dragged node
            TreeNode newNode = (TreeNode)e.Data.GetData("System.Windows.Forms.TreeNode");

            // Check destination mode
            if (!(DestinationNode == newNode) && DestinationNode.Text=="Group")
            {
                TreeNode newNodeClone = (TreeNode)newNode.Clone();//add

                // add a clone
                //DestinationNode.Nodes.Add((TreeNode)newNode.Clone());
                DestinationNode.Nodes.Add(newNodeClone);

                // expand the new node
                DestinationNode.Expand();

                // remove the original node
                newNode.Remove();

                //add - create groups of controls drag under construction
                if (newNodeClone.PrevNode != null)
                {
                    Control prevControl = (Control)newNodeClone.PrevNode.Tag;
                    Control control = (Control)newNodeClone.Tag;

                    var compositeGraphic = (CompositeGraphic)DestinationNode.Tag;


                    if (!compositeGraphic.uc.Contains(prevControl))
                    {
                        compositeGraphic.uc.Controls.Add(prevControl);
                    }
                    if (!compositeGraphic.uc.Controls.Contains(control))
                    {
                        compositeGraphic.uc.Controls.Add(control);
                    }

                    if (!panel.Controls.Contains(compositeGraphic.uc))
                    {
                        panel.Controls.Add(compositeGraphic.uc);
                    }
                }

                var parent = newNodeClone.Parent;

                if (parent == null)
                {
                    return;
                }
                else
                {
                    var compositeGraphic = (CompositeGraphic)DestinationNode.Tag/*newNodeClone.Parent.Tag*/; //Kan ook veranderd naar destination node  >?
                    string shapeType = newNodeClone.Text;

                    switch (shapeType)
                    {
                        case "Ellipse":
                            Ellipse el = (Ellipse)newNodeClone.Tag;
                            compositeGraphic.Add(el);
                            break;
                        case "Box":
                            Box b = (Box)newNodeClone.Tag;
                            compositeGraphic.Add(b);
                            break;
                    }
                    //compositeGraphic.Print();
                }
            }