How to get related entities in lightswitch RIA domain service?

Question

I have set up my DomainService and here is the data structure(one CombinedStadium may
have many CombindeEcoStatus)
public class CombinedStadium
[Key]
public int SiteId { get; set; }
[Include]
[Association("Stadium_EcoStatus", "SiteId", "StadiumId")]
public IQueryable<CombindeEcoStatus> EcoStatus { get; set; }
public class CombindeEcoStatus
private CombinedStadium _combinedStadium;
[Key]
public int EcoId { get; set; }
public int Year {get;set;}
public int StadiumId { get; set; }
[Include]
[Association("Stadium_EcoStatus", "StadiumId", "SiteId", IsForeignKey = true)]
public virtual CombinedStadium Stadium
get { return this._combinedStadium; }
set
this._combinedStadium = value;
if (value == null)
this.StadiumId = value.SiteId;
the query is
[Query(IsDefault = true)]
public IQueryable<CombinedStadium> GetAllStadiums()
var stadiumsQuery = from stadium in this.Context.StadiumSet
select new
SiteId = stadium.Id
return stadiumsQuery;
When I consume this RIA service in my lightswitch app as datasource,and the result looks as same as the Original lightswitch Data Source.
Question:When I query the "CombinedStadium" in HTML client. I can't use the "expand" keyword to get the "EcoStatus" Items which belong to the selected
"CombinedStadium" items.the query code is below:
//streetIds, openIds are query parameters
//streetIds is parameter for query the "CombinedStadiumItem" table
//openIds is parameter for query the "CombindeEcoStatusItem" table
myapp.activeDataWorkspace
.WCF_RIA_ServiceData
.CombindedStadiumQuery(streetIds, openIds)
.expand('EcoStatus')
.execute()
.then(function(proItems) {
var test = proItems.results;
addPin2Map(test);
loadStadiumInfoGrid(test);
the browser throw "error 501".
So I query the "CombinedStadiumItem" table alone.the code is below: 
//streetIds, openIds are query parameters
//streetIds is parameter for query the "CombinedStadiumItem" table
//openIds is parameter for query the "CombindeEcoStatusItem" table
myapp.activeDataWorkspace
.WCF_RIA_ServiceData
.CombindedStadiumQuery(streetIds,openIds)
.execute()
.then(function(proItems) {
var test = proItems.results;
addPin2Map(test);
loadStadiumInfoGrid(test);
myapp.activeDataWorkspace
.WCF_RIA_ServiceData
.RiaEcostatusQuery(streetIds,openIds)
.execute()
.then(function(proItems) {
var test = proItems;
and the query code in server :
partial void CombindedStadiumQuery_PreprocessQuery(string streetPara, string openPara, ref IQueryable < CombinedStadiumItem > query) {
var street = ParseParaStr(streetPara);
if (street != null) {
query = query.Where(e => street.Contains(e.Street));
var open = ParseParaStr(openPara);
if (open != null) {
//when I try to access "EcoStatus" property in "CombindedStadiumItem" table,it throws error
query = query.Where(e => e.EcoStatus.Any(eco => open.Contains(eco.OpenStatus)));
//when I try to access "Stadium" property in "CombindedEcoStatusItem" table,it throws error
partial void RiaEcostatusQuery_PreprocessQuery(string streetPara, string openPara, ref IQueryable < CombindeEcoStatusItem > query) {
var street = ParseParaStr(streetPara);
if (street != null) {
//when I try to access "Stadium" property in "CombindedEcoStatusItem" table,it throws error
query = query.Where(e => street.Contains(e.Stadium.Street));
var open = ParseParaStr(openPara);
if (open != null) {
query = query.Where(e => e.EcoStatus.Any(eco => open.Contains(eco.OpenStatus)));
Now, I can not get "CombindedEcoStatusItem" that related selected "CombindedStadiumItem" respectively.
How can I  get related entities when I use lightswitch RIA service in  HTML Client query?
Thanks!!!

Answer 1

How to write to the event log is not a WPF topic. Please ask C# questions in the C# forum:
https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?forum=csharpgeneral
There is an example of how to the event log using C# code available here:
https://support.microsoft.com/en-us/kb/307024?wa=wsignin1.0
This sample code should work:
string sSource;
string sLog;
string sEvent;
sSource = "My application name";
sLog = "Application";
sEvent = "Log initialization";
if (!System.Diagnostics.EventLog.SourceExists(sSource))
System.Diagnostics.EventLog.CreateEventSource(sSource, sLog);
System.Diagnostics.EventLog.WriteEntry(sSource, sEvent);
System.Diagnostics.EventLog.WriteEntry(sSource, sEvent,
System.Diagnostics.EventLogEntryType.Warning, 234);
The event will get added to Event Viewer->Windows Logs->Application.
Please remember to close your threads by marking helpful posts as answer and then start a new thread in the appropriate forum if you have a new question. And please don't ask several questions in the same thread.