button inside textbox custom control

Question

create a textbox control in windows form
and add this code in FormLoad Event.

               Button btn = new Button();
            btn.Parent = textBox1;


            textBox1.Controls.Add(btn);


            btn.BackColor = Color.AliceBlue;
            Cursor.Current = Cursors.WaitCursor;
            btn.Dock = DockStyle.Right;
            btn.Text = "Search!";