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asp.netiis-7.net-4.0exceptionw3wp

Which Asp.net exceptions can do what?


If I write this code

  protected void Page_Load(object sender, EventArgs e)
    {
        Page_Load(sender, e);
    }

I get the an Error (endless recursion):

enter image description here

and the w3wp.exe process is terminated from task manager.

Fine...

however if i do:

throw new ApplicationException(); //or SystemException();

it appears in just a regular exception page. ( w3wp.exe is still up).

questions :

  • what kind of exceptions causing the w3wp.exe to shutdown ?
  • what kind of exceptions causing the Application Pool to shutdown ?

p.s. according to what ive just written , please think about the following scenario : i can write a web page , host my site in a farm of sites , and i can terminate the whole w3wp.exe process by creating recursion ..... ( also others will have trouble)...

Can you please answer my questions ?

thanks.


Solution

  • This is most likely the famous StackoverflowException. It's caused by an infinite loop since you're calling the method Page_Load again and again.

    From MSDN:

    In prior versions of the .NET Framework, your application could catch a StackOverflowException object (for example, to recover from unbounded recursion). However, that practice is currently discouraged because significant additional code is required to reliably catch a stack overflow exception and continue program execution.

    Starting with the .NET Framework version 2.0, a StackOverflowException object cannot be caught by a try-catch block and the corresponding process is terminated by default. Consequently, users are advised to write their code to detect and prevent a stack overflow. For example, if your application depends on recursion, use a counter or a state condition to terminate the recursive loop. Note that an application that hosts the common language runtime (CLR) can specify that the CLR unload the application domain where the stack overflow exception occurs and let the corresponding process continue. For more information, see ICLRPolicyManager Interface and Hosting Overview.

    You may want to have a look at this answer:

    https://stackoverflow.com/a/4802309/284240