网页全屏显示

注意，<iframe> 标签全屏时需要在标签中添加 allowfullscreen 属性

// 全屏
function handleFullScreen() {
  var de = document.documentElement
  if (de.requestFullscreen) {
    de.requestFullscreen()
  } else if (de.mozRequestFullScreen) {
    de.mozRequestFullScreen()
  } else if (de.webkitRequestFullScreen) {
    de.webkitRequestFullScreen()
  } else if (de.msRequestFullscreen) {
    de.msRequestFullscreen()
  } else {
    alert('当前浏览器不支持全屏操作')
  }
}

// 取消全屏
function exitFullScreen() {
  if (document.exitFullscreen) {
    document.exitFullscreen()
  } else if (document.mozCancelFullScreen) {
    document.mozCancelFullScreen()
  } else if (document.webkitExitFullscreen) {
    document.webkitExitFullscreen()
  } else {
    alert('当前浏览器不支持取消全屏操作')
  }
}