js按钮控制全屏和退出全屏

功能介绍：想用按钮控制页面进入全屏和退出全屏，下面给大家介绍几个函数requestFullscreen、exitFullScreen，不同浏览器名称不一样！

1、进入全屏

var docElm = document.documentElement;
if (docElm.requestFullscreen) {  //W3C
	docElm.requestFullscreen();
} else if (docElm.mozRequestFullScreen) {   //FireFox
	docElm.mozRequestFullScreen();
} else if (docElm.webkitRequestFullScreen) {  //Chrome等
	docElm.webkitRequestFullScreen();
} else if (elem.msRequestFullscreen) {  //IE11
	elem.msRequestFullscreen();
}

2、退出全屏

if (document.exitFullScreen) {
	document.exitFullScreen();
} else if (document.mozCancelFullScreen) {
	document.mozCancelFullScreen();
} else if (document.webkitExitFullscreen) {
	document.webkitExitFullscreen();
} else if (document.msExitFullscreen) {
	document.msExitFullscreen();
}