// 点击进入全屏 方法、

var fullscreen=function(){

    elem=document.body;

    if(elem.webkitRequestFullScreen){

        elem.webkitRequestFullScreen();

    }else if(elem.mozRequestFullScreen){

        elem.mozRequestFullScreen();

    }else if(elem.requestFullScreen){

        elem.requestFullscreen();

    }else{

        //浏览器不支持全屏API或已被禁用

    }

}

// 点击退出全屏 方法

var exitFullscreen=function(){

    var elem=document;

    if(elem.webkitCancelFullScreen){

        elem.webkitCancelFullScreen();

    }else if(elem.mozCancelFullScreen){

        elem.mozCancelFullScreen();

    }else if(elem.cancelFullScreen){

        elem.cancelFullScreen();

    }else if(elem.exitFullscreen){

        elem.exitFullscreen();

    }else{

        //浏览器不支持全屏API或已被禁用

    }

}