兼容手机端屏幕

<script type="text/javascript">
var version = parseFloat(RegExp.$1);
var phoneScale = parseInt(window.screen.width) / 640;
if (/Android (\d+\.\d+)/.test(navigator.userAgent) && version > 2.3 ) {
document.write('<meta name="viewport" content="width=640, maximum-scale=' + phoneScale + ', minimum-scale=' + phoneScale + ', user-scalable=no , target-densitydpi=device-dpi">');
}else{
document.write('<meta name="viewport" content="width=640, user-scalable=no , target-densitydpi=device-dpi">');
}
//if( window.innerWidth != 640 ){ document.getElementsByTagName("html")[0].setAttribute("style","zoom:"+phoneScale);}
//固定分辨率:适配腾讯新闻及微信
</script>