// param 为 参数的名称

function getParameter(param)
{
var query = window.location.search;
var iLen = param.length;
var iStart = query.indexOf(param);
if (iStart == -1)
　return "";
iStart += iLen + 1;
var iEnd = query.indexOf("&", iStart);
if (iEnd == -1)
　return query.substring(iStart);
return query.substring(iStart, iEnd);
}

var url=window.location .href;
　var aa=url.indexOf(''='');
if (aa == -1)
　return "";
　url=url.substring(aa+1);
　window.alert(url);

<script language="JScript">
<!-
var LocString=String(window.document.location.href);
function GetQueryString(str){
var rs=new RegExp("(^|)"+str+"=([^&]*)(&|$)","gi").exec(LocString),tmp;
if(tmp=rs)return tmp[2];
return "没有这个参数";
}
alert("日记编号："+GetQueryString("log_id"));
alert("分类编号："+GetQueryString("cat_id"));
alert("所在页数："+GetQueryString("page"));
-->
</script>