Error checking

Posted on 2000-03-16
Last Modified: 2010-04-16
In this program I'm writing, a user is prompted to enter an integer. (variable name WIDTH) The user is then prompted for the HEIGHT. (another integer)

What should I do when the user enters something that is not a integer? (ie: a character.) Currently I receive a runtime error. (#106 invalid numeric format.)

I have tried using the VAL command, but it does not want to work if the user enters something like "x"

I'd apprecate any help.

Question by:Kory
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
LVL 32

Expert Comment

ID: 2627100
The best option is to use VAL.

Why doesn't that work for you?

I think you first need to declare a string variable. Use this when you ask for the integer values

   Height, Width, ErrorCode : Integer;
   Question : String[5];


Write('Height : ');
Val(Question, Height, ErrorCode);
Until ErrorCode=0;


Write('Width : ');
Val(Question, Width, ErrorCode);
Until ErrorCode=0;

I'm not sure if my syntax is exactly correct. I'm typing it directly into this box.

Try to make use of the errorcode variable. It gives you "the result" of the VAL-procedure.



Expert Comment

ID: 2628269
>>I'm not sure if my syntax is exactly correct

Batalf: that's the proper syntas, and it works that way.

Kory: you don't have another option; Val() procedure is the only thing you have to do what you need.

I can add that variable "errorcode" will contain the position of the offending byte, i.e.:

     S:='1234X'; Val(S, I, ErrorCode);

in this example, ErrorCode will return 4 ('cause the 4th byte was unaccepted).

LVL 32

Accepted Solution

Batalf earned 50 total points
ID: 2628300
Se my comment

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Let's recap what we learned from yesterday's Skyport Systems webinar.
Choosing a core focus or particular set of features and options can be tough. To help out, we’re going to highlight a handful of things your business needs on one of your social media pages. In other words, if one of these is missing, you should imp…
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…
Add bar graphs to Access queries using Unicode block characters. Graphs appear on every record in the color you want. Give life to numbers. Hopes this gives you ideas on visualizing your data in new ways ~ Create a calculated field in a query: …

623 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question