我为我的应用程序不期望的每个条件创建了异常。UserNameNotValidException, PasswordNotCorrectException等。

然而,我被告知我不应该为这些条件创造例外。在我的UML中,那些是主要流程的异常,那么为什么它不应该是异常呢?

是否有创建异常的指导或最佳实践?


当前回答

我有三种情况。

Bad or missing input should not be an exception. Use both client side js and server side regex to detect, set attributes and forward back to the same page with messages. The AppException. This is usually an exception that you detect and throw with in your code. In other words these are ones you expect (the file does not exist). Log it, set the message, and forward back to the general error page. This page usually has a bit of info about what happened. The unexpected Exception. These are the ones you don't know about. Log it with details and forward them to a general error page.

希望这能有所帮助

其他回答

异常类就像“正常”类。当一个新类“是”一个不同类型的对象,具有不同的字段和不同的操作时,您可以创建一个新类。

As a rule of thumb, you should try balance between the number of exceptions and the granularity of the exceptions. If your method throws more than 4-5 different exceptions, you can probably merge some of them into more "general" exceptions, (e.g. in your case "AuthenticationFailedException"), and using the exception message to detail what went wrong. Unless your code handles each of them differently, you needn't creates many exception classes. And if it does, may you should just return an enum with the error that occured. It's a bit cleaner this way.

首先,如果API的用户对特定的、细粒度的故障不感兴趣,那么为他们设置特定的异常就没有任何价值。

由于通常不可能知道什么可能对用户有用,一个更好的方法是有特定的异常,但确保它们继承自一个公共类(例如,std::exception或其在c++中的派生类)。这允许您的客户端捕获特定的异常(如果他们愿意的话),或者捕获更一般的异常(如果他们不关心的话)。

我有三种情况。

Bad or missing input should not be an exception. Use both client side js and server side regex to detect, set attributes and forward back to the same page with messages. The AppException. This is usually an exception that you detect and throw with in your code. In other words these are ones you expect (the file does not exist). Log it, set the message, and forward back to the general error page. This page usually has a bit of info about what happened. The unexpected Exception. These are the ones you don't know about. Log it with details and forward them to a general error page.

希望这能有所帮助

如果用户名无效或密码不正确,这不是一个例外。这些都是在正常操作流程中应该预料到的事情。异常不属于正常程序操作的一部分,而且相当罕见。

我不喜欢使用异常,因为仅仅通过查看调用就无法判断一个方法是否引发了异常。这就是为什么只有当你不能以一种体面的方式处理这种情况时才应该使用异常(比如“内存不足”或“电脑着火了”)。

其他人建议不应该使用异常,因为在正常流程中,如果用户输入错误,就会出现错误的登录。我不同意,我不明白其中的道理。与打开文件相比。如果该文件不存在或由于某种原因不可用,则框架将抛出异常。使用上述逻辑是微软的一个错误。他们应该返回一个错误代码。解析、webrequest等也一样。

I don't consider a bad login part of a normal flow, it's exceptional. Normally the user types the correct password, and the file does exist. The exceptional cases are exceptional and it's perfectly fine to use exceptions for those. Complicating your code by propagating return values through n levels up the stack is a waste of energy and will result in messy code. Do the simplest thing that could possibly work. Don't prematurely optimize by using error codes, exceptional stuff by definition rarely happens, and exceptions don't cost anything unless you throw them.