先写点css样式：

*{margin:0;padding:0}

.btn1{

position:absolute;right:0;bottom:0;

z-index:23;

}

.div1{

position:relative;z-index:1;

width:423px;

height:230px;

}

这是全屏的封装函数：

function   aaa(element){

if(element.requestFullscreen){

element.requestFullscreen();

}else if(element.mozRequestFullScreen){

element.mozRequestFullscreen();

}else if(element.webkitRequestFullscreen){

element.webkitRequestFullscreen();

}else if(element.msRequestFullscreen){

element.msRequestFullscreen();

}

}

这是缩小的封装函数：

function   bbb(){

if(document.exitFullscreen){

document.exitFullscreen();

}else if(document.mozExitFullscreen){

document.mozExcitFullscreen();

}else if(document.webkitExitFullscreen){

document.webkitExitFullscreen();

}

}

函数调用

window.οnlοad=function(){

varoV=document.getElementById('ov');

varoBtn=document.getElementById('btn1')；

oBtn.οnclick=function(){

aaa(document.getElementById('ov'));

};

oV.οndblclick=function(){

bbb();

};

};