Unable to create a record in ms crm 2015 online using html webresource

Hi,

I am unable to create the custom entity record using XmlHttpRequest   .

please fix the issue.

function createPortalRole()
{
var mage_portalrole = new Object();
var PortalRoleName=document.getElementById('portalrole').value;
mage_portalrole.mage_rolename = PortalRoleName;

var jsonPortalRole = window.JSON.stringify(mage_portalrole);
//Create the PortalRole

var createPortalRoleReq = new XMLHttpRequest();

createPortalRoleReq.open("POST", parent.Xrm.Page.context.getClientUrl() + "/XRMServices/2011/OrganizationData.svc/mage_portalroleSet", true);
createPortalRoleReq.setRequestHeader("Accept", "application/json");
createPortalRoleReq.setRequestHeader("Content-Type", "application/json; charset=utf-8");
createPortalRoleReq.onreadystatechange = function () {
createPortalRoleReqCallBack(this);
};
createPortalRoleReq.send(jsonPortalRole);

function createPortalRoleReqCallBack(createPortalRoleReq) {
if (createPortalRoleReq.readyState == 4 /* complete */) {
createPortalRoleReq.onreadystatechange = null; //avoids memory leaks
if (createPortalRoleReq.status == 201) {
//Success
var newPortalRole = JSON.parse(createPortalRoleReq.responseText).d;
}
else {
//Failure
errorHandler(createPortalRoleReq, newPortalRole);
}
}
};

function errorHandler(XMLHttpRequest, textStatus, errorThrown)
{ alert("Error : " + textStatus + ": " + JSON.parse(XMLHttpRequest.responseText).error.message.value); }