用html5(requestFullscreen) js实现点击一个按钮使浏览器全屏效果

项目中需要将后台浏览器的窗口全屏，也就是我们点击一个按钮要实现按F11全屏的效果。 在HTML5中,W3C制定了关于全屏的API，就可以实现全屏幕的效果，也可以让页面中的图片，视频等全屏目前只有google chrome 15 +, safri5.1+,firfox10+,IE11支持
查看例子，一睹为快！
全屏

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

退出全屏

if (document.exitFullscreen) { 
    document.exitFullscreen(); 
} 
else if (document.mozCancelFullScreen) { 
    document.mozCancelFullScreen(); 
} 
else if (document.webkitCancelFullScreen) { 
    document.webkitCancelFullScreen(); 
} 
else if (document.msExitFullscreen) { 
    document.msExitFullscreen(); 
}

事件监听

document.addEventListener("fullscreenchange", function () { 
fullscreenState.innerHTML = (document.fullscreen)? "" : "not ";}, false); 

document.addEventListener("mozfullscreenchange", function () { 
fullscreenState.innerHTML = (document.mozFullScreen)? "" : "not ";}, false); 

document.addEventListener("webkitfullscreenchange", function () { 
fullscreenState.innerHTML = (document.webkitIsFullScreen)? "" : "not ";}, false); 
document.addEventListener("msfullscreenchange", function () { 
fullscreenState.innerHTML = (document.msFullscreenElement)? "" : "not ";}, false);

全屏样式设置

在浏览器全屏的使用我们还可以进行样式设置

html:-moz-full-screen { 
    background: red; 
} 

html:-webkit-full-screen { 
    background: red; 
} 

html:fullscreen { 
    background: red; 
}