实现在vue中element-ui的el-dialog弹框拖拽及拉伸、双击全屏的两种方法（二）

我会带着你远行 2022-12-09 15:55 478阅读 0赞

## 封装的拖拽代码 ##

在utils/el-drag-dialog文件夹中创建drag.js和index.js两个文件

drag.js

export default {
      bind(el, binding, vnode, oldVnode) {
        // 弹框可拉伸最小宽高
        const minWidth = 400
        const minHeight = 300
    
        // 初始非全屏
        let isFullScreen = false
    
        // 当前顶部高度
        let nowMarginTop = 0
    
        // 获取弹框头部（这部分可双击全屏）
        const dialogHeaderEl = el.querySelector('.el-dialog__header')
    
        // 弹窗
        const dragDom = el.querySelector('.el-dialog')
    
        // 给弹窗加上overflow auto；不然缩小时框内的标签可能超出dialog；
        dragDom.style.overflow = 'auto'
    
        // 清除选择头部文字效果
        // dialogHeaderEl.onselectstart = new Function("return false");
    
        // 头部加上可拖动cursor
        dialogHeaderEl.style.cursor = 'move'
    
        // 获取原有属性 ie dom元素.currentStyle 火狐谷歌 window.getComputedStyle(dom元素, null);
        const sty = dragDom.currentStyle || window.getComputedStyle(dragDom, null)
        const moveDown = e => {
          // 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
    
          // 获取到的值带px 正则匹配替换
          let styL, styT
    
          // 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 (sty.left.includes('%')) {
            styL = +document.body.clientWidth * (+sty.left.replace(/\%/g, '') / 100)
            styT = +document.body.clientHeight * (+sty.top.replace(/\%/g, '') / 100)
          } else {
            styL = +sty.left.replace(/\px/g, '')
            styT = +sty.top.replace(/\px/g, '')
          }
    
          document.onmousemove = function(e) {
            // 通过事件委托，计算移动的距离
            const l = e.clientX - disX
            const t = e.clientY - disY
    
            // 移动当前元素
            dragDom.style.left = `${l + styL}px`
            dragDom.style.top = `${t + styT}px`
    
            // 将此时的位置传出去
            // binding.value({x:e.pageX,y:e.pageY})
          }
    
          document.onmouseup = function(e) {
            document.onmousemove = null
            document.onmouseup = null
          }
        }
    
        dialogHeaderEl.onmousedown = moveDown
        // 当前宽高
        let nowWidth = 0
        // let nowHight = 0
        // 双击头部全屏效果
        dialogHeaderEl.ondblclick = e => {
          if (isFullScreen === false) {
            // nowHight = dragDom.clientHeight
            nowWidth = dragDom.clientWidth
            nowMarginTop = dragDom.style.marginTop
    
            dragDom.style.left = 0
            dragDom.style.top = 0
            dragDom.style.height = '100VH'
            dragDom.style.width = '100VW'
            dragDom.style.marginTop = 0
    
            isFullScreen = true
    
            dialogHeaderEl.style.cursor = 'initial'
            dialogHeaderEl.onmousedown = null
          } else {
            dragDom.style.height = 'auto'
            dragDom.style.width = nowWidth + 'px'
            dragDom.style.marginTop = nowMarginTop
    
            isFullScreen = false
    
            dialogHeaderEl.style.cursor = 'move'
            dialogHeaderEl.onmousedown = moveDown
          }
        }
    
        dragDom.onmousemove = function(e) {
          // let moveE = e
    
          if (
            e.clientX > dragDom.offsetLeft + dragDom.clientWidth - 10 ||
            dragDom.offsetLeft + 10 > e.clientX
          ) {
            dragDom.style.cursor = 'w-resize'
          } else if (
            el.scrollTop + e.clientY >
            dragDom.offsetTop + dragDom.clientHeight - 10
          ) {
            dragDom.style.cursor = 's-resize'
          } else {
            dragDom.style.cursor = 'default'
    
            dragDom.onmousedown = null
          }
    
          dragDom.onmousedown = e => {
            const clientX = e.clientX
            const clientY = e.clientY
            const elW = dragDom.clientWidth
            const elH = dragDom.clientHeight
            const EloffsetLeft = dragDom.offsetLeft
            const EloffsetTop = dragDom.offsetTop
    
            dragDom.style.userSelect = 'none'
    
            const ELscrollTop = el.scrollTop
    
            // 判断点击的位置是不是为头部
            if (
              clientX > EloffsetLeft &&
              clientX < EloffsetLeft + elW &&
              clientY > EloffsetTop &&
              clientY < EloffsetTop + 100
            ) {
              // 如果是头部在此就不做任何动作，以上有绑定dialogHeaderEl.onmousedown = moveDown;
            } else {
              document.onmousemove = function(e) {
                // 移动时禁用默认事件
                e.preventDefault()
    
                // 左侧鼠标拖拽位置
                if (clientX > EloffsetLeft && clientX < EloffsetLeft + 10) {
                  // 往左拖拽
                  if (clientX > e.clientX) {
                    dragDom.style.width = elW + (clientX - e.clientX) * 2 + 'px'
                  }
    
                  // 往右拖拽
                  if (clientX < e.clientX) {
                    if (dragDom.clientWidth < minWidth) {
                      console.log()
                    } else {
                      dragDom.style.width = elW - (e.clientX - clientX) * 2 + 'px'
                    }
                  }
                }
    
                // 右侧鼠标拖拽位置
                if (
                  clientX > EloffsetLeft + elW - 10 &&
                  clientX < EloffsetLeft + elW
                ) {
                  // 往左拖拽
                  if (clientX > e.clientX) {
                    if (dragDom.clientWidth < minWidth) {
                      console.log()
                    } else {
                      dragDom.style.width = elW - (clientX - e.clientX) * 2 + 'px'
                    }
                  }
    
                  // 往右拖拽
                  if (clientX < e.clientX) {
                    dragDom.style.width = elW + (e.clientX - clientX) * 2 + 'px'
                  }
                }
    
                // 底部鼠标拖拽位置
                if (
                  ELscrollTop + clientY > EloffsetTop + elH - 20 &&
                  ELscrollTop + clientY < EloffsetTop + elH
                ) {
                  // 往上拖拽
                  if (clientY > e.clientY) {
                    if (dragDom.clientHeight < minHeight) {
                      console.log()
                    } else {
                      dragDom.style.height = elH - (clientY - e.clientY) * 2 + 'px'
                    }
                  }
    
                  // 往下拖拽
                  if (clientY < e.clientY) {
                    dragDom.style.height = elH + (e.clientY - clientY) * 2 + 'px'
                  }
                }
              }
    
              // 拉伸结束
              document.onmouseup = function(e) {
                document.onmousemove = null
    
                document.onmouseup = null
              }
            }
          }
        }
      }
    }

如果不需要缩放的drag.js可以用下面的代码

export default {
      bind(el, binding, vnode) {
        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 getStyle = (function() {
          if (window.document.currentStyle) {
            return (dom, attr) => dom.currentStyle[attr]
          } else {
            return (dom, attr) => getComputedStyle(dom, false)[attr]
          }
        })()
    
        dialogHeaderEl.onmousedown = (e) => {
          // 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 dragDomWidth = dragDom.offsetWidth
          const dragDomHeight = dragDom.offsetHeight
    
          const screenWidth = document.body.clientWidth
          const screenHeight = document.body.clientHeight
    
          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 = getStyle(dragDom, 'left')
          let styT = getStyle(dragDom, 'top')
    
          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;`
    
            // emit onDrag event
            vnode.child.$emit('dragDialog')
          }
    
          document.onmouseup = function(e) {
            document.onmousemove = null
            document.onmouseup = null
          }
        }
      }
    }

index.js

import drag from './drag'
    
    const install = function(Vue) {
      Vue.directive('el-drag-dialog', drag)
    }
    
    if (window.Vue) {
      window['el-drag-dialog'] = drag
      Vue.use(install); // eslint-disable-line
    }
    
    drag.install = install
    export default drag

然后在需要调用的地方调用 v-el-drag-dialog

<el-dialog :visible.sync="modalShow" :before-close="modalClose" v-el-drag-dialog>
    	内容内容内容
    </el-dialog>
    import elDragDialog from "@/assets/js/el-drag-dialog";//导入组件
    <script>
    export default {
      data() {
        return {
          modalShow: false
        };
      },
      directives: { elDragDialog },//调用组件
      methods: {
        init() {
          this.modalShow = true;
        },
        modalClose() {
          this.modalShow = false;
        }
      }
    };
    </script>

参考：[vue+el-dialog页面引用可拖拽弹窗组件][vue_el-dialog]

[vue_el-dialog]: https://blog.csdn.net/yaoqiuquan/article/details/104540133/