jquery实现拖拽调整Div大小

                    resizeW = false;
                    resizeH = true;
                    document.body.style.cursor = “s-resize”;
                }
                if (0 < target.offsetLeft + w – _startX && target.offsetLeft + w – _startX < size && (0 > target.offsetTop + h – _startY || target.offsetTop + h – _startY > size)) {
                    resizeW = true;
                    resizeH = false;
                    document.body.style.cursor = “w-resize”;
                }
                if (0 < target.offsetLeft + w – _startX && target.offsetLeft + w – _startX < size && 0 < target.offsetTop + h – _startY && target.offsetTop + h – _startY < size) {
                    resizeW = true;
                    resizeH = true;
                    document.body.style.cursor = “se-resize”;
                }
                $(target).on(‘mousedown’, downHandler);
            } else {
                resizeW = false;
                resizeH = false;
                $(target).off(‘mousedown’, downHandler);
            }
        }
        function downHandler(event) {
            target = event.target || event.srcElement;