在c＃中停靠mdi控件

Question

I have a main form in a panel on the left thats clickable, depending on what you click a new type of form opens. on the righti have another panel where i want to dock the forms that have been opened from clicking on the left.

How can i get the forms to add in a list under one another in the panel on the right? the issue with the code below is that it adds the first element fine. However when i add the second element they both dissapear behind the panel :/

private void addToPanel2(Form o)
{
    if (o is Form)
    {

        if (panel2.Controls.Count == 0)
        {
            o.MdiParent = this;
            panel2.Controls.Add(o);
            o.Dock = DockStyle.Top;
            o.Show();
        }
        else
        {
            //then we know that this is an addable data item
            foreach (Form obj in panel2.Controls)
            {
                if(obj.GetType().Name.Equals(o.GetType().Name))
                {
                    //we dont want to add it as the data type is already open
                    MessageBox.Show("This data item must already be open. Please Check.");
                }
                else
                {
                    // add it as its not in there
                    Form f = (Form)obj;
                    f.MdiParent = this;
                    f.Dock = DockStyle.Top;
                    f.Show();
                }
            }
        }
    }

thanks

Answer 1

This is not possible, an MDI child form cannot be a child control of a panel. Adding a non-MDI form to a panel is an iffy proposition as well but is supported. Call its SetTopLevel() method, passing false, set its Visible property to true. You also have to set its FormBorderStyle property to None, it no longer behaves properly as a top-level window.

This just turns it into a UserControl. You are better off actually making it a UserControl, that uses a lot less resources and is much better documented.