@degal-directive/dragdialog/src/drag.js

弹窗框拖拽移动和改变大小指令

export const dialogDrag = {
  bind(el, binding) {
    // 自定义属性，判断是否可拖拽
    if (!binding.value) return
    const dialogHeaderEl = el.querySelector('.el-dialog__header')
    const dragDom = el.querySelector('.el-dialog')
    dialogHeaderEl.style.cssText += ';cursor:move;'
    dragDom.style.cssText += ';top:0px;'

    // 获取原有属性 ie dom元素.currentStyle 火狐谷歌 window.getComputedStyle(dom元素, null);
    const sty = (function () {
      if (document.body.currentStyle) {
        // 在ie下兼容写法
        return (dom, attr) => dom.currentStyle[attr]
      } else {
        return (dom, attr) => getComputedStyle(dom, false)[attr]
      }
    })()

    dialogHeaderEl.onmousedown = (e) => {
      // 判断当前是否为全屏状态
      const path = e.path || (e.composedPath && e.composedPath())
      const isFull = path.find((s) => {
        if (s.className === undefined) {
          return false
        } else {
          return s.className.indexOf('is-fullscreen') > -1
        }
      })

      if (isFull !== undefined) {
        return
      }

      // 鼠标按下，计算当前元素距离可视区的距离
      const disX = e.clientX - dialogHeaderEl.offsetLeft
      const disY = e.clientY - dialogHeaderEl.offsetTop

      const screenWidth = document.body.clientWidth // body当前宽度
      const screenHeight = document.documentElement.clientHeight // 可见区域高度(应为body高度，可某些环境下无法获取)

      const dragDomWidth = dragDom.offsetWidth // 对话框宽度
      const dragDomheight = dragDom.offsetHeight + 2 // 对话框高度

      const minDragDomLeft = dragDom.offsetLeft
      const maxDragDomLeft = screenWidth - dragDom.offsetLeft - dragDomWidth

      const minDragDomTop = dragDom.offsetTop
      const maxDragDomTop = screenHeight - dragDom.offsetTop - dragDomheight

      // 获取到的值带px 正则匹配替换
      let styL = sty(dragDom, 'left') // 为兼容ie
      if (styL === 'auto') styL = '0px'
      let styT = sty(dragDom, 'top')
      // 注意在ie中 第一次获取到的值为组件自带50% 移动之后赋值为px
      if (styL.includes('%')) {
        styL = +document.body.clientWidth * (+styL.replace(/%/g, '') / 100)
        styT = +document.body.clientHeight * (+styT.replace(/%/g, '') / 100)
      } else {
        styL = +styL.replace(/px/g, '')
        styT = +styT.replace(/px/g, '')
      }

      document.onmousemove = function (e) {
        // 通过事件委托，计算移动的距离
        let left = e.clientX - disX
        let top = e.clientY - disY
        // 边界处理
        if (-left > minDragDomLeft) {
          left = -minDragDomLeft
        } else if (left > maxDragDomLeft) {
          left = maxDragDomLeft
        }

        if (-top > minDragDomTop) {
          top = -minDragDomTop
        } else if (top > maxDragDomTop) {
          top = maxDragDomTop
        }

        // 移动当前元素
        dragDom.style.cssText += `;left:${left + styL}px;top:${top + styT}px;`
      }

      document.onmouseup = function () {
        document.onmousemove = null
        document.onmouseup = null
      }
      return false
    }
  },
  update: function (el) {
    const dragDom = el.querySelector('.el-dialog')
    if (el.style.display === 'none') {
      dragDom.style.cssText += `;left:0px;top:0px;`
    }
  }
}

export const dialogChange = {
  bind(el, binding) {
    // 自定义属性，判断是否可拉伸
    if (!binding.value) return
    var dragDom = el.querySelector('.el-dialog')

    let dragMouse
    // 在弹出框的右下角添加可拉伸标志 class='mouse'
    for (let i = 0; i < dragDom.childNodes[2].childNodes.length; i++) {
      if (dragDom.childNodes[2].childNodes[i].className === 'mouse') {
        dragMouse = dragDom.childNodes[2].childNodes[i]
      }
    }

    // 鼠标拖拽
    dragMouse.onmousedown = (e) => {
      // content区域
      const content = document.querySelector('html')
      const disX = e.clientX - dragDom.offsetWidth
      const disY = e.clientY - dragDom.offsetHeight

      document.onmousemove = function (e) {
        e.preventDefault() // 移动时禁用默认事件
        // 通过事件委托，计算移动的距离
        let width = e.clientX - disX
        let height = e.clientY - disY
        if (width > content.offsetWidth && height < content.offsetHeight) {
          dragDom.style.height = `${height}px`
        } else if (width < content.offsetWidth && height > content.offsetHeight) {
          dragDom.style.width = `${width}px`
        } else if (width < content.offsetWidth && height < content.offsetHeight) {
          dragDom.style.width = `${width}px`
          dragDom.style.height = `${height}px`
        }
      }
      document.onmouseup = function () {
        document.onmousemove = null
        document.onmouseup = null
      }
      return false
    }
  }
}