JavaScript读取URL参数代码

function request(paras) {
var url = location.href;
var paraString = url.substring(url.indexOf("?") + 1, url.length).split("&");
var paraObj = {}
for (i = 0; j = paraString[i]; i++) {
paraObj[j.substring(0, j.indexOf("=")).toLowerCase()] = j.substring(j.indexOf("=") + 1, j.length);
}
var returnValue = paraObj[paras.toLowerCase()];
if (typeof (returnValue) == "undefined") {
return "";
} else {
return returnValue;
}
}