/// <summary>
/// Begins executing this async request.
/// </summary>
/// <param name="callback">The AsyncCallback delegate.</param>
/// <param name="state">An object that contains state information for this request.</param>
/// <returns>An IAsyncResult that references the asynchronous request.</returns>
internal IAsyncResult BeginExecute(AsyncCallback callback, object state)
{
this.Validate();
IEwsHttpWebRequest request = this.BuildEwsHttpWebRequest();
WebAsyncCallStateAnchor wrappedState = new WebAsyncCallStateAnchor(this, request, callback /* user callback */, state /* user state */);
// BeginGetResponse() does not throw interesting exceptions
IAsyncResult webAsyncResult = request.BeginGetResponse(SimpleServiceRequestBase.WebRequestAsyncCallback, wrappedState);
return(new AsyncRequestResult(this, request, webAsyncResult, state /* user state */));
}
