Drag any of the controls in the. NET WinForm form with the mouse __.net

In the WinForm form, drag through the mouse to change the position of the control. During the drag process, follow the mouse to display a black box that is the size of the dragged control to simulate the drag effect. The following figure: This is the source code. A button control is dragged here. If you want, you can also change the cursor as you drag. using system; using system.collections.generic; using system.componentmodel; using system.data; using system.drawing; using system.text; using system.windows.forms; Namespace windowsapplication1 {    public partial class formdrag :  form     {        //The controls that will be dragged          private Control control;         public formdrag ()          {            initializecomponent ();             this. Paint += new system.windows.forms.painteventhandler (this. Formdrag_paint);              control = new button ();             control. Mousedown += new mouseeventhandler (Control_mousedown);             control. Mousemove += new mouseeventhandler (Control_mousemove);             control. Mouseup += new mouseeventhandler (Control_mouseup);             this. Controls.Add (Control);                      }                  //mouse down coordinates (relative coordinates of control controls)         Point  mousedownpoint = point.empty;          //the rectangle that displays the drag effect         rectangle rect =  Rectangle.Empty;         //is dragging         bool  isDrag = false;         void control_mousedown (object sender,  Mouseeventargs e)         {             if  (E.button == mousebuttons.left)              {                 mouseDownPoint = e.Location;                 //the size of the record control                 rect =  cOntrol. Bounds;             }         &NBSP}         void control_mousemove (Object sender,  mouseeventargs e)         {             if  (E.button == mousebuttons.left)              {                 isDrag = true;                 //Reset the rect position, Follow the mouse to move the                 rect. Location = getpointtoform (New point) (e.location.x - mousedownpoint.x, e. LOCATION.Y - MOUSEDOWNPOINT.Y));  &nBsp;              this. Refresh ();                               }         }         void control_mouseup (object sender,  Mouseeventargs e)         {             if  (E.button == mousebuttons.left)              {                 if  (Isdrag)                  {                     isDrag = false;                      //move control to the place where the mouse is released                      control. Location = rect. Location;                      this. Refresh ();                 }                  reset ();             }         &NBSP}         //Reset Variable          private void reset ()         {             mousedownpoint = point.empty ;             rect = Rectangle.Empty;             isDrag = false;        &NBSP}         //form Redraw          private void formdrag_paint (object sender,  Painteventargs e)         {             if  (Rect != rectangle.empty)              {                 if  (Isdrag)                 &nbsp {//Draw a black box of the same size as control                      e.graphics.drawrectangle (Pens.black, rect);                 }                  else                  {                     e. Graphics.drawrectangle (this. New pen BackColor),  rect);                 }              }         }         //converts the coordinates of control controls to relative to the form's coordinates.         private point getpointtoform (point p)          {            return  This. PointToClient (Control. Pointtoscreen (p));         }              &NBSP}}