异步调用WCF的方法需要小心的地方

直接使用下面的代码，由于client对象占用的资源没有被释放，会导致内存泄露
GetSimServiceReference.GetSimServiceClient client = new GetSimServiceReference.GetSimServiceClient()
client.computerSimAsync(DepartmentNo, FileID, F_intput.Length, ReadStringArrayFromStrings());
上面的问题，可以使用下面的方法来避免

                    using (GetSimServiceReference.GetSimServiceClient client = new GetSimServiceReference.GetSimServiceClient())

                    {

                        client.computerSimA(DepartmentNo, FileID, F_intput.Length, ReadStringArrayFromStrings());

                    }

但是如果使用异步调用的方式，会导致调用不到远程服务，并且没有任何异常提示，很是让人摸不到头脑

                    using (GetSimServiceReference.GetSimServiceClient client = new GetSimServiceReference.GetSimServiceClient())

                    {

                       client.computerSimAsync(DepartmentNo, FileID, F_intput.Length, ReadStringArrayFromStrings());

                    }

最后，采用了如下的代码：

                    try

                    {

                        GetSimServiceReference.GetSimServiceClient client = new GetSimServiceReference.GetSimServiceClient();

                        client.computerSim(DepartmentNo, FileID, F_intput.Length, ReadStringArrayFromStrings());

                        if (client.State != CommunicationState.Faulted) client.Close();

                    }

                    catch (CommunicationObjectFaultedException cofe)

                    {

                        ShowException.SaveLogAsTXTInfoex("调用WCF服务失败，异常信息：" + cofe.Message);

                    }

                    catch (Exception ex)

                    {

                        ShowException.SaveLogAsTXTInfoex("调用WCF服务失败，异常信息：" + ex.Message+f_intput.FullName);

                    }