May 1995
Beginner
508 pages
16h 14m
English
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 4. Error Handling and Debugging
Errors, bugs, and therefore debugging are a part of life for a programmer. As the saying goes, if you haven’t made any mistakes, then you aren’t trying hard enough.
Dealing with errors actually involves two very different processes: error handling and debugging. Error handling is a combination of coding and methodology that allows your program to anticipate user and other errors. It allows you to create a robust program. Error handling does not involve weeding out bugs and glitches in your source code, although some of the error handling techniques covered in this chapter can be used to great advantage at the debugging stage. In general, error handling should be part of your overall program plan, so that when you have an error-free script, nothing is going to bring it to a screeching halt. With some sturdy error handling in place, your program should be able to keep running despite all the misuse that your users can—and certainly will—throw at it.
The following ASP page illustrates some simple error handling:
<HTML>
<HEAD><TITLE>Error Checking</TITLE>
<BODY>
<SCRIPT LANGUAGE=VBSCRIPT RUNAT=SERVER>
Dim n, x
n = 10
x = Request.Form.Item("txtNumber")
If x = 0 Or Not IsNumeric(x) Then
Response.Write "x is an invalid entry"
Else
y = n / x
Response.Write y
End If
</SCRIPT>
</BODY>
</HTML>The error handling in this example is the best kind—it stops
an error before it can occur. Suppose you hadn’t used the
conditional If...Else statement and had allowed ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.