JS实现页面全屏功能

<div id="videobox"></div>

進入全屏事件：

launchFullscreen(element) {
	//此方法不可以在異步任務中執行，否則火狐無法全屏
	if(element.requestFullscreen) {
		element.requestFullscreen();
	} else if(element.mozRequestFullScreen) {
		element.mozRequestFullScreen();
	} else if(element.msRequestFullscreen) {
		element.msRequestFullscreen();
	} else if(element.oRequestFullscreen) {
		element.oRequestFullscreen();
	} else if(element.webkitRequestFullscreen) {
		element.webkitRequestFullScreen();
	} else {
		var docHtml = document.documentElement;
		var docBody = document.body;
		var videobox = document.getElementById('videobox');
		var width = window.screen.width;
		var height = window.screen.height;
		var cssText = "width:" + width + ";height:" + height + ";overflow:hidden;";
		docHtml.style.cssText = cssText;
		docBody.style.cssText = cssText;
		document.IsFullScreen = true;
	}
}lau