IsNull Variable Testing Function

IsNull Variable Testing Function
Null values are different than just a blank string. They are actual EMPTY spots. You can't do most logical operations with a null value.

For example, if you have a TotalCount variable and it is set to NULL, you can't see if it is greater than zero or less than zero or anything else. It has no value, it is NULL. So you need to check for that before you start working with it.

The syntax, if you had a TotalCount variable, would be:

NoCount = IsNull(TotalCount)
if NoCount = TRUE then
response.write "you must enter the count value first."
end if

Variable Testing Functions

Introduction to ASP Ebook

Download this ebook to get everything you need to know about learning ASP - from a step by step tutorial to function lists, sample code, common errors and solutions, and much more! 101 pages.




RSS
Editor's Picks Articles
Top Ten Articles
Previous Features
Site Map





Content copyright © 2022 by Lisa Shea. All rights reserved.
This content was written by Lisa Shea. If you wish to use this content in any manner, you need written permission. Contact Lisa Shea for details.