MS Dynamics CRM - Login user's security role using javascript

I have one situation, login user has multiple security roles, if the login user has permission for particular role, show some buttons/fields otherwise the hide buttons/fields.

It is not stright forward to find out the security role, So i wrote one javascript to find out the security role.

Here i am checking the user has "Content Manager" security role or not.

var CMRole = CheckUserRole("Content Manager");
if (CMRole) {
    //true to show buttons
} else {
    //false to hide buttons
}

This function will get all the user's security role Id, passing security role id to get the security role name. If it match, it is true otherwise false.

function CheckUserRole(roleName) {
    var currentUserRoles = Xrm.Page.context.getUserRoles();
    for (var i = 0; i < currentUserRoles.length; i++) {
        var userRoleId = currentUserRoles[i];
         var userRoleName = GetRoleName(userRoleId);
         if (userRoleName == roleName) {
            return true;
         }
    }
    return false;
}

This function calling odata web service and get the each security role name.

 function GetRoleName(userRoleId) {
     var selectQuery = "RoleSet?$top=1&$filter=RoleId eq guid'" + userRoleId + "'&$select=Name";
     var odataSelect = GetServerUrl() + selectQuery;
     //alert(odataSelect);
     var roleName = null;
     $.ajax({
         type: "GET",
         async: false,
         contentType: "application/json; charset=utf-8",
         datatype: "json",
         url: odataSelect,
         beforeSend: function (XMLHttpRequest) { XMLHttpRequest.setRequestHeader("Accept", "application/json"); },
         success: function (data, textStatus, XmlHttpRequest) {
             var result = data.d;
             if (!!result) {
                 roleName = result.results[0].Name;
             }
         },
         error: function (XmlHttpRequest, textStatus, errorThrown) {
             //alert('OData Select Failed: ' + odataSelect);
         }
     });
     return roleName;
 }