Revision: 45420
Initial Code
Initial URL
Initial Description
Initial Title
Initial Tags
Initial Language
at April 29, 2011 22:30 by nehringryan
Initial Code
Need to make sure a variable exists in Coldfusion? Use one of the options below to first check for a value passed from the server/form/whatever. If none is sent, for any reason whatsoever (var error, db error, net hiccup etc...), this code will ensure you still have a variable with a valid defaulted value to ensure 1 problem doesn't become 2.
<!--- Example of Coldfusion's IsDefined Function --->
<!--- This first way is probably easer to understand to newer programmers or people coming from other languages to CF. --->
<!--- Check if the form sent in a value, and if it didn't, then manually set it. Nothing too mindblowing huge here. --->
<cfif isDefined("Form.firstname")>
<cfoutput>Hello, #Form.firstname#!</cfoutput>
<cfelse>
<cfoutput>Hello, stranger!</cfoutput>
</cfif>
<!--- Example of Coldfusions <cfparam> tag used instead --->
<!--- Using cfparam tag is evern easier, less code & more the
technically right way do this in CF (maybe?... lol ) ) --->
<cfparam name="Form.firstname" default="stranger">
<cfoutput>Hello, #Form.firstname#!</cfoutput>
One clean, little, and simple to remember Coldfusion tag replaces a "CFIF" conditional process & all the declararative code you'd need to set those values by hand.This is a pretty small example, but the implications are pretty apparent if you had to check maybe 20 variables etc.
Initial URL
http://ryannehring.com/
Initial Description
Initial Title
Coldfusion Variable Checking / Setting Default
Initial Tags
Initial Language
ColdFusion