<!-- el-tooltip 文字提示 -->
<div class="btn-fullscreen" @click="handleFullScreen">
 <el-tooltip effect="dark" :content="fullscreen " placement="bottom">
  <i class="el-icon-rank"></i>
 </el-tooltip>
</div>

data(){
return {
fullscreen: false
}
} 
 
// 全屏事件
  handleFullScreen(){
  let element = document.documentElement;
  if (this.fullscreen) {
   if (document.exitFullscreen) {
   document.exitFullscreen();
   } else if (document.webkitCancelFullScreen) {
   document.webkitCancelFullScreen();
   } else if (document.mozCancelFullScreen) {
   document.mozCancelFullScreen();
   } else if (document.msExitFullscreen) {
   document.msExitFullscreen();
   }
  } else {
   if (element.requestFullscreen) {
   element.requestFullscreen();
   } else if (element.webkitRequestFullScreen) {
   element.webkitRequestFullScreen();
   } else if (element.mozRequestFullScreen) {
   element.mozRequestFullScreen();
   } else if (element.msRequestFullscreen) {
   // IE11
   element.msRequestFullscreen();
   }
  }
  this.fullscreen = !this.fullscreen;
},