在Web上处理客户端和服务器端错误的正确方法是什么？

Question

I'm new to web development (though not new to WinForms developmet) and I wanted to know the correct and efficient way to handle errors both on the client side as well as the server side.

For example, user enters a bad zip code (using letters), I want to notify the user of the bad zip code entered, how do I handle this?

I'm assuming this would be on the client side but can anyone show me an example code? What scripting language should you use? Should you display a message on the screen? Should you make an error message visible? What is the standard way of doing this?

Example two: user clicks on something that runs a query in a server database. An error occurs. How do I notify the user of the error?

Usually in Win Forms I can just do this:

try
{
     CreateDirectoriesAndSystemFiles();
}
catch (Exception ex)
{
     ErrorLogger.LogError(ex.Source, ex.TargetSite.ToString(), "Error creating directories!; " + ex.Message);
     MessageBox.Show(ex.Message, "Error creating directories!", MessageBoxButtons.OK, MessageBoxIcon.Error);
     return;
}

How can I mimic the above in a web environment?

Answer 1

1 For client notification, you can use Validators

Link : http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.requiredfieldvalidator.aspx

This link is about RequiredFieldValidator

You have also CompareValidator, CustomValidator etc ....

Link : http://msdn.microsoft.com/en-us/library/ms972961.aspx

That's good solution.

2 For treatment exception, you can use Global.asax and Applicatio_Error

Link : http://msdn.microsoft.com/en-us/library/24395wz3%28v=vs.100%29.aspx

Answer 2

Most people use jQuery validate as its very easy to use whilst being extremely powerful and flexible. Docs are here http://docs.jquery.com/Plugins/Validation . Microsoft include them by default in MVC 3 & 4 and use it for model validation client side so if you're using MS stack and MVC thats another good reason to use it. Things get a bit different in Web Forms as you tend to use the built in validation controls which handle both client and server side out of the box references here http://msdn.microsoft.com/en-us/library/a0z2h4sw(v=vs.100).aspx - these are exnsible through the Custom Validator types that allow you to specify server and client side methods that you write yourself to handle bespoke functionality. Hope this helps!

Answer 3

asp.net can do the same try/catch handling for server-side errors.

as far as input validation goes, you should look into Asp.net Input Validation Controls

Answer 4

For example #2 you can redirect to error page

try
{
     CreateDirectoriesAndSystemFiles();
}
catch (Exception ex)
{
     Response.Redirect("Error.aspx?err=" + ex.GetType());
}

and on the Error.aspx page just parse err parameter and show it to user.

Good idea is to log this in db (if you use it).

Answer 5

Depends on if you are using webforms or MVC.

In MVC, generally for server side error handling I create an ApplicationController class that inherits and put my error handling, logging and redirect logic there then have my controllers inherit this class.

For webforms I would create an error control and include this in my master page and feed the server side errors back to this.

In either case, for client side you can use jquery and javascript for field validations.

Answer 6

you're asking a lot of questions, i'll try and answer a few:

1. concerning validation (the zipcode example)- firstly, and I cannot stress this enough- allways validate things on the server side client-side code, such as javascript, can be easily turned off / circumvented. Even if you check things on the client side (and you should)- always check them on the server side as well.
   That said, what validation framework to use depends on what display framework you're using. I've used jquery's validation in the past, and was pleased with it.

2. What scripting language should you use? well, if there was one correct answer to that one, then there wouldn't be much point in having so many, right :)
   Anyway, jQuery is very popular, but so is knockoutJS , and I hear angular is gaining in popularity. just see which one you like

3. for unexpected errors on the server-side, there had been some good suggestions. I like Aghilas Yakoub's.

Best of luck