drag 自定义指令

import Vue from 'vue'

const drag = Vue.directive('drag', {

    bind: function(el) {},

    inserted: function(el) {

        el.onmousedown = function(e) {

            var disx = e.pageX - el.offsetLeft

            var disy = e.pageY - el.offsetTop

            document.onmousemove = e => {

                el.style.left = e.pageX - disx + 'px'

                el.style.top = e.pageY - disy + 'px'

            }

            document.onmouseup = () => {

                document.onmousemove = document.onmouseup = null

            }

        }

    },

    updated: function(el) {},

})

export default drag