private void GetUser()
{
//连接服务端
EndpointAddress address = new EndpointAddress(new Uri(Application.Current.Host.Source, "/DBService.svc"));
//建立客户端对象
DBServiceClient client = new DBServiceClient(new BasicHttpBinding(), address);
//添加处理事件
client.GetUserCompleted += new EventHandler<GetUserCompletedEventArgs>(client_GetUserCompleted);
//传入参数
client.GetUserAsync(txtUsername.Text, pbPassword.Password);
}