很多web项目需要用到移动端或PC端自适应，分享一段js代码给大家，以下代码亲测有效。

<script type="text/javascript">

$(document).ready(function(){

var sUserAgent = navigator.userAgent.toLowerCase();

var bIsIpad = sUserAgent.match(/ipad/i) == "ipad";

var bIsIphoneOs = sUserAgent.match(/iphone os/i) == "iphone os";

var bIsMidp = sUserAgent.match(/midp/i) == "midp";

var bIsUc7 = sUserAgent.match(/rv:1.2.3.4/i) == "rv:1.2.3.4";

var bIsUc = sUserAgent.match(/ucweb/i) == "ucweb";

var bIsAndroid = sUserAgent.match(/android/i) == "android";

var bIsCE = sUserAgent.match(/windows ce/i) == "windows ce";

var bIsWM = sUserAgent.match(/windows mobile/i) == "windows mobile";

if (bIsIpad || bIsIphoneOs || bIsMidp || bIsUc7 || bIsUc || bIsAndroid || bIsCE || bIsWM) {

   alert('移动端设备')

} else {

alert('pc端设备')

}

});

</script>

大部分机型测试基本没问题。