方法一（flv.js为哔哩哔哩开源框架）

安装flv.js

npm install flv.js --save

引入：（在使用的页面引入）

import flvjs from "flv.js"

html:(video本身不支持flv格式视频，通过flv.js转换)

<video id="videoElement"></video>

js:(填写自己的url)

  var videoElement = document.getElementById('videoElement');
        var flvPlayer = flvjs.createPlayer({
            type: 'flv',
            url: 'http://video.flv'
        });
        flvPlayer.attachMediaElement(videoElement);
        flvPlayer.load();
        flvPlayer.play();

方法2：

下载依赖：

npm i xgplayer-flv.js --save
npm i xgplayer --save

引入：

import FlvJsPlayer from 'xgplayer-flv.js';
import Player from 'xgplayer';

直接上代码（我封装在一个组件中）

<!--xgplayer  -->
<template>
  <div class="cam" v-if="mainCamUrl != ''">
    <div class="video" v-show="isPlay" :id="camDOMid" ref="video"></div>
  </div>
</template>
<script>
  import FlvJsPlayer from 'xgplayer-flv.js';
  import Player from 'xgplayer';
  export default {
    name: "XgPlayer",
    data() {
      return {
        isPlay: false,
        player: null,
        camDOMid:'liveId',
        mainCamUrl:'http:flv格式视频'
      }
    },
    mounted() {
      this.getData();
    },
    methods: {
      // 设置视频配置(注意：initPlayer应放在异步函数里或mounted之后，不可在created里直接加载，否则不生效)
      initPlayer(url) {
        console.log("this.camDOMid", this.camDOMid);
        var player = document.getElementById(this.camDOMid);
        this.isPlay = true;
        this.player = new FlvJsPlayer({
          id: this.camDOMid,
          url: url,
          fitVideoSize: 'auto',
          hasStart: true,
          autoplay: true, //自动播放，设置自动播放必要参数
          autoplayMuted: true, //自动播放静音，设置自动播放参数必要参数
          volume: 0,
          defaultMuted: true,
          isLive: true,
          playsinline: false,
          screenShot: true,
          fluid: true,
          aspectRatio: '16:9',
          whitelist: [''],
          ignores: ['time'],
          closeVideoClick: true,
          // errorTips: '<span class="app-error">无视频源</span>',
          customConfig: {
            isClickPlayBack: false
          },
          flvOptionalConfig: {
            enableWorker: true,
            enableStashBuffer: true, //启用缓存
            stashInitialSize: 4096, //缓存大小4m
            lazyLoad: false,
            lazyLoadMaxDuration: 40 * 60,
            autoCleanupSourceBuffer: true,
            autoCleanupMaxBackwardDuration: 35 * 60,
            autoCleanupMinBackwardDuration: 30 * 60
          } //flv.js可选配置项 [flv.js配置](https://github.com/bilibili/flv.js/blob/master/docs/api.md#config)
        });
        console.log("this.player", this.player);
        this.player.once('complete', () => {
          console.log('complete')//以下这段我没成功。
          try {
            this.player.play() // 尝试再次执行播放
            setTimeout(() => { // 500毫秒后检测
              if (!this.player.hasStart && this.player.currentTime ===
                0) { // hasStart返回false，并且播放时间还是0，那么就可以认为自动播放失效了
                isAutoPlay = false;
              }
            }, 500)
          } catch (e) {
            console.log(e);
          }
        })
      },
      getData() {
        let playUrl = this.mainCamUrl //播放地址
        this.initPlayer(playUrl)
      },
    },
    beforeDestroy() {
      if (this.player) {
        this.player.destroy();
      }
      console.log('销毁了');
	  },
  }
</script>

<style scoped>
  .cam {
    position: relative;
  }
  .video {
    width: 100%;
    height: 100%;
  }
</style>

基于方法2的播放flv视频，完成项目要求的拖拽盒子

<template>
  <div>
    <div class="drag-follow-box" id="drag-video-id">
      <div class="drag-top" @mousedown="draggableFun($event)">
        <img src="../assets/close.png" class="drag-close" @click="closeDragBox($event)">
        <span class="drag-device">
          {
   {deviceName}}
          <i class="member-status-icon info-status"></i>
        </span>
      </div>
      <div :id="dragPlayId" ref="video2" v-show="isPlay" class="drag-bottom" v-if="mainCamUrl != ''"></div>
    </div>
  </div>

</template>

<script>
  import FlvJsPlayer from 'xgplayer-flv.js';
  import Player from 'xgplayer';
  export default {
    name: "DragFlv",
    data() {
      return {
        isPlay: false,
        player: null,
        deviceName: '设备',
        dragPlayId: 'liveId2',
        mainCamUrl: 'http:flv视频链接'
      }
    },
    mounted() {
      this.getVideo()
    },
    methods: {
      getVideo() {
        let playUrl = this.mainCamUrl //播放地址
        this.initPlayer(playUrl)
      },
      // 设置视频配置(注意：initPlayer应放在异步函数里或mounted之后，不可在created里直接加载，否则不生效)
      initPlayer(url) {
        let _this = this
        var player = document.getElementById(this.dragPlayId);
        this.isPlay = true;
        console.log(this.dragPlayId)
        this.player = new FlvJsPlayer({
          id: _this.dragPlayId,
          url: url,
          fitVideoSize: 'auto',
          hasStart: true,
          autoplay: true, //自动播放，设置自动播放必要参数
          autoplayMuted: true, //自动播放静音，设置自动播放参数必要参数
          volume: 0,
          defaultMuted: true,
          isLive: true,
          playsinline: false,
          screenShot: true,
          fluid: true,
          aspectRatio: '16:9',
          whitelist: [''],
          ignores: ['time'],
          closeVideoClick: true,
          errorTips: '<span class="app-error">无视频源</span>',
          customConfig: {
            isClickPlayBack: false
          },
          flvOptionalConfig: {
            enableWorker: true,
            enableStashBuffer: true, //启用缓存
            stashInitialSize: 4096, //缓存大小4m
            lazyLoad: false,
            lazyLoadMaxDuration: 40 * 60,
            autoCleanupSourceBuffer: true,
            autoCleanupMaxBackwardDuration: 35 * 60,
            autoCleanupMinBackwardDuration: 30 * 60
          }
        });
        console.log("this.player", this.player);
        this.player.once('complete', () => {
          console.log('complete') //以下这段我没成功。
          try {
            this.player.play() // 尝试再次执行播放
            setTimeout(() => { // 500毫秒后检测
              if (!this.player.hasStart && this.player.currentTime ===
                0) { // hasStart返回false，并且播放时间还是0，那么就可以认为自动播放失效了
                isAutoPlay = false;
              }
            }, 500)
          } catch (e) {
            console.log("hhhh")
            console.log(e);
          }
        })
      },
      draggableFun(ev) {
        console.log("点击")
        ev.preventDefault()
        let div = ev.target.parentNode
        let dragFlag = false;
        let x, y;
        div.onmousedown = function(e) {
          e.preventDefault()
          dragFlag = true;
          e = e || window.event;
          // 获取鼠标在元素上的位置（鼠标按下时在元素上得位置）
          x = e.clientX - div.offsetLeft;
          y = e.clientY - div.offsetTop;
          console.log(div.offsetLeft)
          console.log(div.offsetTop)
          console.log("-------------")
        };

        div.onmousemove = function(e) {
          e.preventDefault()
          if (dragFlag) {
            e = e || window.event;
            div.style.left = e.clientX - x + "px";
            div.style.top = e.clientY - y + "px";
          }
        };
        // 鼠标抬起事件
        div.onmouseup = function(e) {
          e.preventDefault()
          dragFlag = false;
        };
      },
      //关闭直播盒子
      closeDragBox(ev) {
        ev.target.parentNode.parentNode.remove()
        if (this.player) {
          this.player.destroy()
        }
      },

    },
    beforeDestroy() {
      if (this.player) {
        this.player.destroy();
      }
      console.log('销毁了');
    },
  }
</script>

<style scoped>
  .drag-follow-box {
    overflow: hidden;
    display: flex;
    flex-direction: column;
    width: 500px;
    height: 400px;
    border: 1px solid rgb(226, 226, 226);
    position: absolute;
    z-index: 2001;
    top: 35%;
    left: 400px;
  }

  .drag-top {
    width: 100%;
    height: 40px;
    border-bottom: 1px solid rgb(226, 226, 226);
    background: rgb(255, 255, 255);
    cursor: move;
  }

  .drag-bottom {
    flex: 1 1 0%;
    background: rgb(224, 224, 224);
    width: 100%;
    height: 100%;
    border: 0px;
  }

  .drag-close {
    float: right;
    margin: 12px;
    width: 14px;
    height: 14px;
    cursor: pointer;
  }

  .drag-device {
    float: left;
    margin: 9px 9px 9px 30px;
  }

  .member-status-icon {
    display: block;
    width: 10px;
    height: 10px;
    min-width: 10px;
    border: 2px solid rgb(255, 255, 255);
    border-radius: 50%;
    position: absolute;
    left: 6px;
    top: 13px;
    background-color: rgb(159, 155, 155);
  }
</style>