Question: I'm trying to find out if a url variable exists, and if it doesn't, make sure that it's not empty.

This does not work:

```
<cfif IsDefined('URL.affiliateId') and is not "">
    //
</cfif>

```

Answer: 
```
<cfif structKeyExists(url, 'affiliateID') and trim(url.affiliateID) neq "">...</cfif>

```
To ignore most white space

```
<cfif IsDefined('URL.affiliateId') and len(trim(URL.affiliateId))>
    value is defined and not empty
</cfif>

```

... or alternately 

```
<cfif IsDefined('URL.affiliateId') and len(trim(URL.affiliateId)) gt 0>
    value is defined and not empty
</cfif>

```