H5实现页面全屏显示脚本

function openFullScreen() {
	var doc = document.documentElement;
	if (doc.requestFullscreen) {
		doc.requestFullscreen();
	} else if (doc.msRequestFullscreen) {
		doc.msRequestFullscreen(); //早期IE浏览器
	} else if (doc.webkitRequestFullScreen) {
		doc.webkitRequestFullScreen(); //早期Chrome浏览器
	} else if (doc.mozRequestFullScreen) {
		doc.mozRequestFullScreen();  //早期火狐浏览器
	}
}

function exitFullScreen() {
	var doc = document;
	if(doc.exitFullscreen) {
		doc.exitFullscreen();
	} else if(doc.msExitFullscreen) {
		doc.msExitFullscreen(); //早期IE浏览器
	} else if(doc.webkitExitFullscreen) {
		doc.webkitExitFullscreen(); //早期Chrome浏览器
	} else if(doc.mozCancelFullScreen) {
		doc.mozCancelFullScreen(); //早期火狐浏览器
	}
}

function isFullScreen(){
	return !!(document.fullscreenElement || document.msFullScreenElement || document.webkitFullScreenElement || document.mozFullScreenElement);
}