function refresh(url, key){
    var key= (key || 't') +'=';      //默认是"t"
    var reg=new RegExp(key+'\\d+');  //正则:t=1472286066028
    var timestamp=+new Date();
    if(url.indexOf(key)>-1){         //有时间戳,直接更新
        return url.replace(reg,key+timestamp);
    }else{  //没有时间戳,加上时间戳
        if(url.indexOf('\?')>-1){
            var urlArr=url.split('\?');
            if(urlArr[1]){
                return urlArr[0]+'?'+key+timestamp+'&'+urlArr[1];
            }else{
                return urlArr[0]+'?'+key+timestamp;
            }
        }else{
            if(url.indexOf('#')>-1){
                return url.split('#')[0]+'?'+key+timestamp+location.hash;
            }else{
                return url+'?'+key+timestamp;
            }
        }
    }
}

在写实际代码之前做好CSS样式重置可避免一系列稀奇古怪的问题

body,ol,ul,h1,h2,h3,h4,h5,h6,p,th,td,dl,
dd,form,fieldset,legend,input,textarea,select{margin:0;padding:0}
body{font:12px "宋体","Arial Narrow",
HELVETICA;background:#fff;-webkit-text-size-adjust:100%}
a{text-decoration:none}
em{font-style:normal}
li{list-style:none}
img{border:0;vertical-align:middle}
table{border-collapse:collapse;border-spacing:0}
p{word-wrap:break-word}