catch (ArgumentNullException e) {    return MailSendStatus.ErrorCannotSend;} catch 
(ObjectDisposedException e) {    return MailSendStatus.ErrorCannotSend;} catch 
(InvalidOperationException e) {    return MailSendStatus.ErrorCannotSend;

我不喜欢这个。 ArgumentNull，ObjectDisposed是编程错误（和InvalidOperation一样）。您不应该将它们分解为SMTP错误，而是将其修复。 Fpr这个，崩溃的程序是好的（并放出一个堆栈跟踪）。方法快速失败。不要重新排除异常，你不知道如何处理，而InvalidOperationException，ObjectDisposedException表示状态有问题，ArbumentNullException是一个用法/ ui错误。

I dont like this. ArgumentNull, ObjectDisposed are programming errors (as is InvalidOperation). You should not break them down to a SMTP error but have them fixed. Fpr this, crashing the program is good (and putting out a stack trace). Approach "fail fast". Dont rethriow exceptions you dont know how to handle, and InvalidOperationException, ObjectDisposedException indicate something is wrong with the state, ArbumentNullException is a usage / ui error.