在保持Web.Config安全的同时从WebMethod获取错误消息

Question

I have a page that's doing jQuery Ajax calls to a WebMethod in one of my ASPX pages. In some cases, my WebMethod is throwing an exception with an error message. This error message is really important for the UI, because it tells what to say to the user, so he can fix his form.

This is working fine in development environnement. But, in my production Web.Config, I need to keep customErrors set to "On", so I wont show important information. Moreover, my IIS is overriding HTTP 500 errors too.

I tried the WebServices from ASMX, and it was working perfectly. IIS wasn't overriding my HTTP 500, and customErrors was not hiding the message sent by the WebService. But migrating all my ASPX's WebMethods to ASMX files is not possible for now.

I'm looking for a guideline. How my UI can gets my WebMethod's errors, while keeping my Web.Config safe for production?

Answer 1

You should never show a yellow screen of death to a user.

Instead, consider implementing a Response object, contaning a boolean Success, an ErrorMessage (string) and the actual result data if needed.

You can then use a JavaScript callback and check if the call succeded. If it did not, just alert() the error message.