Ler parametros da url

function getURLParam(strParamName){

var strReturn = "";
var strHref = window.location.href;
if ( strHref.indexOf("?") > -1 ){
var strQueryString = "&" + strHref.substr(strHref.indexOf("?") + 1); //.toLowerCase();
var aQueryString = strQueryString.split("&");
for ( var iParam = 0; iParam < aQueryString.length; iParam++ ){
if (aQueryString[iParam].indexOf(strParamName + "=") > -1 ){
var aParam = aQueryString[iParam].split("=");
strReturn = aParam[1];
break;
}
}
}
return strReturn;
},