To drag and drop a movie clip we use two function: 1.startDrag() 2.stopDrag().

startDrag(): is used to drag a specified movieClip. MovieClip remain draggage until explicitly

stopped by making call to stopDrag().one movieclip is dragged at a time.

startDrag() uses two parameter: 1.lockCenter:Boolean : Its default value is false.It specifies whether whether the draggable movieclip locked to the point where the user first clicked the sprite .

2.bounds:Rectangle:value relative to the coordinates of the Sprite's parent that specify a constraint rectangle for the Sprite

stopDrag(): It is used to stop the draging movieclip.

Sample application to show the use of this two method:

package 
{

    import flash.display.MovieClip;
    import flash.events.MouseEvent;

    public class Main extends MovieClip
    {
        var rect:MovieClip;

        public function Main()
        {
            // constructor code
            rect = new MovieClip();
            rect.graphics.beginFill(0x660033);
            rect.graphics.drawRect(0, 0, 50, 100);
            this.addChild(rect);

            rect.addEventListener(MouseEvent.MOUSE_DOWN, startDragging);
            rect.addEventListener(MouseEvent.MOUSE_UP, stopDragging);
        }

        private function startDragging(e:MouseEvent):void
        {
            rect.startDrag();
        }

        private function stopDragging(e:MouseEvent):void
        {
            rect.stopDrag();
        }

    }
}