Trapping the exceptionMost errors on the site get handled by the server (IIS) calling the HTTP 500 error handler. In other words, I don't do anything to stop the error, I just let the server stop executing the offending page, and display an error. My handler just displays a prettier error.Exception handling is different. Now I'm providing code to execute when an error occurs, and depending on the error I can do different things. Try again, stop the script, even send an HTML <form> to the user asking him a question. The try...catch blockException handling is very easy to implement. Here is the code that traps exceptions caught when opening a connection to my database:try
{
// open the database, catching any errors that occur
oConnection.Open( sConnectionString );
}
catch ( e )
{
// display error message, and send email
DatabaseException ( e );
// quit running the script completely
Response.End ( );
}
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If any error occurs anywhere between the braces of the try block, then execution will immediately continue with the first statement inside the catch block. A lot of errors can be caught in this way - errors raised by COM components such as the ADODB.Connection shown here, but also arithmetic errors such as divide by zero. In the above example, I'm doing two things in my catch block. I display an error message by calling a function that I'll discuss in a minute, then I stop the script running by calling Response.End (there's little point in continuing if the connection fails). But, back to the function call I made - note that I pass in the variable e that was specified in the catch statement. Part 3: But what is "e"?... | 
