silverlight同步访问WCF

private System.Collections.ObjectModel.ObservableCollection<SilverService.ProspectTaskWork_Entity> workEntitys = null;
private System.Collections.ObjectModel.ObservableCollection<SilverService.ProspectTaskWork_Entity> attentionEntitys = null;
private System.Collections.ObjectModel.ObservableCollection<SilverService.FunctionRight_Entity> functionRights = null;        
private AutoResetEvent EventAttention = null;
private AutoResetEvent EventFunction = null;
private AutoResetEvent[] EventArray = new AutoResetEvent[2];

private void Canvas_Loaded(object sender, RoutedEventArgs e)
{
　　EventAttention = new AutoResetEvent(false);
     EventFunction = new AutoResetEvent(false);
     EventArray[0] = EventAttention;
     EventArray[1] = EventFunction;
     //
     SilverService.SilverLightClient client = new SilverService.SilverLightClient();
     client.GetProspectTaskWorkListByUserIdCompleted += new EventHandler<SilverService.GetProspectTaskWorkListByUserIdCompletedEventArgs>(OnGetProspectTaskWorkListByUserIdCompleted);
     client.GetProspectTaskWorkListByUserIdAsync(SilverService.WorkQueryType.ATTENTION_USERID, m_userId);
     //
     client.GetUserSystemRightsCompleted += new EventHandler<SilverService.GetUserSystemRightsCompletedEventArgs>(OnGetUserSystemRightsCompleted);
     client.GetUserSystemRightsAsync(m_userId);
     //
     client.GetAllProspectTaskWorkCompleted += new EventHandler<SilverService.GetAllProspectTaskWorkCompletedEventArgs>(OnGetAllProspectTaskWorkCompleted);
     client.GetAllProspectTaskWorkAsync();
}

void OnGetProspectTaskWorkListByUserIdCompleted(object sender, SilverService.GetProspectTaskWorkListByUserIdCompletedEventArgs e)
{
　　if (e.Error != null)
     {
     　　//错误处理	private System.Collections.ObjectModel.Ob