Sets the classes for a client on a Web Enrolment. 

By default, when a Web Enrolment is processed, the client in the new enrolment is assigned to all the classes that are in the occurrence that the Web Enrolment is for. Use this method to choose which classes in the occurrence the client is to be assigned to. The classes must be on the occurrence that the Web Enrolment is for. 

A Web Enrolment ID (webEnrolId) is passed as a parameter. This should be the ID returned by the function used to create the web enrolment: AddClientWebEnrolment or AddEmployerWebEnrolment. 

The parameter instanceIds is a List of integers, indicating the Inst_Ids of the classes to assign the client to. The easiest way to get a list of these is to use the GetClassesForOccurrence function to get a list of all classes in the occurrence the Web Enrolment is for. 

A subsequent call to this function for the same Web Enrolment ID will override all the classes assigned on any previous call for that Web Enrolment ID. 

A token is passed for authentication. If the authentication fails, or other errors occur, no price types are recorded. The result of the authentication is represented by a TAuthenticate object. 

Requires a valid registration key entry for the Short Courses feature. 

This function has security level "Protected", and can only be accessed by users that have explicitly been granted permission to the API.

[WebMethod(Description = "Records the specified classes against the existing web enrolment ID")]
public TAuthenticate AddClassesToWebEnrolment(string token, int webEnrolId, List<int> instanceIds);